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2023-06-23workqueue: clean up WORK_* constant types, clarify maskingLinus Torvalds
Dave Airlie reports that gcc-13.1.1 has started complaining about some of the workqueue code in 32-bit arm builds: kernel/workqueue.c: In function ‘get_work_pwq’: kernel/workqueue.c:713:24: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] 713 | return (void *)(data & WORK_STRUCT_WQ_DATA_MASK); | ^ [ ... a couple of other cases ... ] and while it's not immediately clear exactly why gcc started complaining about it now, I suspect it's some C23-induced enum type handlign fixup in gcc-13 is the cause. Whatever the reason for starting to complain, the code and data types are indeed disgusting enough that the complaint is warranted. The wq code ends up creating various "helper constants" (like that WORK_STRUCT_WQ_DATA_MASK) using an enum type, which is all kinds of confused. The mask needs to be 'unsigned long', not some unspecified enum type. To make matters worse, the actual "mask and cast to a pointer" is repeated a couple of times, and the cast isn't even always done to the right pointer, but - as the error case above - to a 'void *' with then the compiler finishing the job. That's now how we roll in the kernel. So create the masks using the proper types rather than some ambiguous enumeration, and use a nice helper that actually does the type conversion in one well-defined place. Incidentally, this magically makes clang generate better code. That, admittedly, is really just a sign of clang having been seriously confused before, and cleaning up the typing unconfuses the compiler too. Reported-by: Dave Airlie <airlied@gmail.com> Link: https://lore.kernel.org/lkml/CAPM=9twNnV4zMCvrPkw3H-ajZOH-01JVh_kDrxdPYQErz8ZTdA@mail.gmail.com/ Cc: Arnd Bergmann <arnd@arndb.de> Cc: Tejun Heo <tj@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-06-22Merge tag 'net-6.4-rc8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from ipsec, bpf, mptcp and netfilter. Current release - regressions: - netfilter: add NFT_TRANS_PREPARE_ERROR to deal with bound set/chain - eth: mlx5e: - fix scheduling of IPsec ASO query while in atomic - free IRQ rmap and notifier on kernel shutdown Current release - new code bugs: - phy: manual remove LEDs to ensure correct ordering Previous releases - regressions: - mptcp: fix possible divide by zero in recvmsg() - dsa: revert "net: phy: dp83867: perform soft reset and retain established link" Previous releases - always broken: - sched: netem: acquire qdisc lock in netem_change() - bpf: - fix verifier id tracking of scalars on spill - fix NULL dereference on exceptions - accept function names that contain dots - netfilter: disallow element updates of bound anonymous sets - mptcp: ensure listener is unhashed before updating the sk status - xfrm: - add missed call to delete offloaded policies - fix inbound ipv4/udp/esp packets to UDPv6 dualstack sockets - selftests: fixes for FIPS mode - dsa: mt7530: fix multiple CPU ports, BPDU and LLDP handling - eth: sfc: use budget for TX completions Misc: - wifi: iwlwifi: add support for SO-F device with PCI id 0x7AF0" * tag 'net-6.4-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (74 commits) revert "net: align SO_RCVMARK required privileges with SO_MARK" net: wwan: iosm: Convert single instance struct member to flexible array sch_netem: acquire qdisc lock in netem_change() selftests: forwarding: Fix race condition in mirror installation wifi: mac80211: report all unusable beacon frames mptcp: ensure listener is unhashed before updating the sk status mptcp: drop legacy code around RX EOF mptcp: consolidate fallback and non fallback state machine mptcp: fix possible list corruption on passive MPJ mptcp: fix possible divide by zero in recvmsg() mptcp: handle correctly disconnect() failures bpf: Force kprobe multi expected_attach_type for kprobe_multi link bpf/btf: Accept function names that contain dots Revert "net: phy: dp83867: perform soft reset and retain established link" net: mdio: fix the wrong parameters netfilter: nf_tables: Fix for deleting base chains with payload netfilter: nfnetlink_osf: fix module autoload netfilter: nf_tables: drop module reference after updating chain netfilter: nf_tables: disallow timeout for anonymous sets netfilter: nf_tables: disallow updates of anonymous sets ...
2023-06-22Merge tag 'cgroup-for-6.4-rc7-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: "It's late but here are two bug fixes. Both fix problems which can be severe but are very confined in scope. The risk to most use cases should be minimal. - Fix for an old bug which triggers if a cgroup subsystem is remounted to a different hierarchy while someone is reading its cgroup.procs/tasks file. The risk is pretty low given how seldom cgroup subsystems are moved across hierarchies. - We moved cpus_read_lock() outside of cgroup internal locks a while ago but forgot to update the legacy_freezer leading to lockdep triggers. Fixed" * tag 'cgroup-for-6.4-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: Do not corrupt task iteration when rebinding subsystem cgroup,freezer: hold cpu_hotplug_lock before freezer_mutex in freezer_css_{online,offline}()
2023-06-21Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2023-06-21 We've added 7 non-merge commits during the last 14 day(s) which contain a total of 7 files changed, 181 insertions(+), 15 deletions(-). The main changes are: 1) Fix a verifier id tracking issue with scalars upon spill, from Maxim Mikityanskiy. 2) Fix NULL dereference if an exception is generated while a BPF subprogram is running, from Krister Johansen. 3) Fix a BTF verification failure when compiling kernel with LLVM_IAS=0, from Florent Revest. 4) Fix expected_attach_type enforcement for kprobe_multi link, from Jiri Olsa. 5) Fix a bpf_jit_dump issue for x86_64 to pick the correct JITed image, from Yonghong Song. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf: Force kprobe multi expected_attach_type for kprobe_multi link bpf/btf: Accept function names that contain dots selftests/bpf: add a test for subprogram extables bpf: ensure main program has an extable bpf: Fix a bpf_jit_dump issue for x86_64 with sysctl bpf_jit_enable. selftests/bpf: Add test cases to assert proper ID tracking on spill bpf: Fix verifier id tracking of scalars on spill ==================== Link: https://lore.kernel.org/r/20230621101116.16122-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21Merge tag 'timers-urgent-2023-06-21' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Thomas Gleixner: "A single regression fix for a regression fix: For a long time the tick was aligned to clock MONOTONIC so that the tick event happened at a multiple of nanoseconds per tick starting from clock MONOTONIC = 0. At some point this changed as the refined jiffies clocksource which is used during boot before the TSC or other clocksources becomes usable, was adjusted with a boot offset, so that time 0 is closer to the point where the kernel starts. This broke the assumption in the tick code that when the tick setup happens early on ktime_get() will return a multiple of nanoseconds per tick. As a consequence applications which aligned their periodic execution so that it does not collide with the tick were not longer guaranteed that the tick period starts from time 0. The fix for this regression was to realign the tick when it is initially set up to a multiple of tick periods. That works as long as the underlying tick device supports periodic mode, but breaks under certain conditions when the tick device supports only one shot mode. Depending on the offset, the alignment delta to clock MONOTONIC can get in a range where the minimal programming delta of the underlying clock event device is larger than the calculated delta to the next tick. This results in a boot hang as the tick code tries to play catch up, but as the tick never fires jiffies are not advanced so it keeps trying for ever. Solve this by moving the tick alignement into the NOHZ / HIGHRES enablement code because at that point it is guaranteed that the underlying clocksource is high resolution capable and not longer depending on the tick. This is far before user space starts, so at the point where applications try to align their timers, the old behaviour of the tick happening at a multiple of nanoseconds per tick starting from clock MONOTONIC = 0 is restored" * tag 'timers-urgent-2023-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick/common: Align tick period during sched_timer setup
2023-06-21bpf: Force kprobe multi expected_attach_type for kprobe_multi linkJiri Olsa
We currently allow to create perf link for program with expected_attach_type == BPF_TRACE_KPROBE_MULTI. This will cause crash when we call helpers like get_attach_cookie or get_func_ip in such program, because it will call the kprobe_multi's version (current->bpf_ctx context setup) of those helpers while it expects perf_link's current->bpf_ctx context setup. Making sure that we use BPF_TRACE_KPROBE_MULTI expected_attach_type only for programs attaching through kprobe_multi link. Fixes: ca74823c6e16 ("bpf: Add cookie support to programs attached with kprobe multi link") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230618131414.75649-1-jolsa@kernel.org
2023-06-21bpf/btf: Accept function names that contain dotsFlorent Revest
When building a kernel with LLVM=1, LLVM_IAS=0 and CONFIG_KASAN=y, LLVM leaves DWARF tags for the "asan.module_ctor" & co symbols. In turn, pahole creates BTF_KIND_FUNC entries for these and this makes the BTF metadata validation fail because they contain a dot. In a dramatic turn of event, this BTF verification failure can cause the netfilter_bpf initialization to fail, causing netfilter_core to free the netfilter_helper hashmap and netfilter_ftp to trigger a use-after-free. The risk of u-a-f in netfilter will be addressed separately but the existence of "asan.module_ctor" debug info under some build conditions sounds like a good enough reason to accept functions that contain dots in BTF. Although using only LLVM=1 is the recommended way to compile clang-based kernels, users can certainly do LLVM=1, LLVM_IAS=0 as well and we still try to support that combination according to Nick. To clarify: - > v5.10 kernel, LLVM=1 (LLVM_IAS=0 is not the default) is recommended, but user can still have LLVM=1, LLVM_IAS=0 to trigger the issue - <= 5.10 kernel, LLVM=1 (LLVM_IAS=0 is the default) is recommended in which case GNU as will be used Fixes: 1dc92851849c ("bpf: kernel side support for BTF Var and DataSec") Signed-off-by: Florent Revest <revest@chromium.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Cc: Yonghong Song <yhs@meta.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/bpf/20230615145607.3469985-1-revest@chromium.org
2023-06-20Merge tag 'trace-v6.4-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix MAINTAINERS file to point to proper mailing list for rtla and rv The mailing list pointed to linux-trace-devel instead of linux-trace-kernel. The former is for the tracing libraries and the latter is for anything in the Linux kernel tree. The wrong mailing list was used because linux-trace-kernel did not exist when rtla and rv were created. - User events: - Fix matching of dynamic events to their user events When user writes to dynamic_events file, a lookup of the registered dynamic events is made, but there were some cases that a match could be incorrectly made. - Add auto cleanup of user events Have the user events automatically get removed when the last reference (file descriptor) is closed. This was asked for to prevent leaks of user events hanging around needing admins to clean them up. - Add persistent logic (but not let user space use it yet) In some cases, having a persistent user event (one that does not get cleaned up automatically) is useful. But there's still debates about how to expose this to user space. The infrastructure is added, but the API is not. - Update the selftests Update the user event selftests to reflect the above changes" * tag 'trace-v6.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/user_events: Document auto-cleanup and remove dyn_event refs selftests/user_events: Adapt dyn_test to non-persist events selftests/user_events: Ensure auto cleanup works as expected tracing/user_events: Add auto cleanup and future persist flag tracing/user_events: Track refcount consistently via put/get tracing/user_events: Store register flags on events tracing/user_events: Remove user_ns walk for groups selftests/user_events: Add perf self-test for empty arguments events selftests/user_events: Clear the events after perf self-test selftests/user_events: Add ftrace self-test for empty arguments events tracing/user_events: Fix the incorrect trace record for empty arguments events tracing: Modify print_fields() for fields output order tracing/user_events: Handle matching arguments that is null from dyn_events tracing/user_events: Prevent same name but different args event tracing/rv/rtla: Update MAINTAINERS file to point to proper mailing list
2023-06-16tick/common: Align tick period during sched_timer setupThomas Gleixner
The tick period is aligned very early while the first clock_event_device is registered. At that point the system runs in periodic mode and switches later to one-shot mode if possible. The next wake-up event is programmed based on the aligned value (tick_next_period) but the delta value, that is used to program the clock_event_device, is computed based on ktime_get(). With the subtracted offset, the device fires earlier than the exact time frame. With a large enough offset the system programs the timer for the next wake-up and the remaining time left is too small to make any boot progress. The system hangs. Move the alignment later to the setup of tick_sched timer. At this point the system switches to oneshot mode and a high resolution clocksource is available. At this point it is safe to align tick_next_period because ktime_get() will now return accurate (not jiffies based) time. [bigeasy: Patch description + testing]. Fixes: e9523a0d81899 ("tick/common: Align tick period with the HZ tick.") Reported-by: Mathias Krause <minipli@grsecurity.net> Reported-by: "Bhatnagar, Rishabh" <risbhat@amazon.com> Suggested-by: Mathias Krause <minipli@grsecurity.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Richard W.M. Jones <rjones@redhat.com> Tested-by: Mathias Krause <minipli@grsecurity.net> Acked-by: SeongJae Park <sj@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/5a56290d-806e-b9a5-f37c-f21958b5a8c0@grsecurity.net Link: https://lore.kernel.org/12c6f9a3-d087-b824-0d05-0d18c9bc1bf3@amazon.com Link: https://lore.kernel.org/r/20230615091830.RxMV2xf_@linutronix.de
2023-06-14tracing/user_events: Add auto cleanup and future persist flagBeau Belgrave
Currently user events need to be manually deleted via the delete IOCTL call or via the dynamic_events file. Most operators and processes wish to have these events auto cleanup when they are no longer used by anything to prevent them piling without manual maintenance. However, some operators may not want this, such as pre-registering events via the dynamic_events tracefs file. Update user_event_put() to attempt an auto delete of the event if it's the last reference. The auto delete must run in a work queue to ensure proper behavior of class->reg() invocations that don't expect the call to go away from underneath them during the unregister. Add work_struct to user_event struct to ensure we can do this reliably. Add a persist flag, that is not yet exposed, to ensure we can toggle between auto-cleanup and leaving the events existing in the future. When a non-zero flag is seen during register, return -EINVAL to ensure ABI is clear for the user processes while we work out the best approach for persistent events. Link: https://lkml.kernel.org/r/20230614163336.5797-4-beaub@linux.microsoft.com Link: https://lore.kernel.org/linux-trace-kernel/20230518093600.3f119d68@rorschach.local.home/ Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Track refcount consistently via put/getBeau Belgrave
Various parts of the code today track user_event's refcnt field directly via a refcount_add/dec. This makes it hard to modify the behavior of the last reference decrement in all code paths consistently. For example, in the future we will auto-delete events upon the last reference going away. This last reference could happen in many places, but we want it to be consistently handled. Add user_event_get() and user_event_put() for the add/dec. Update all places where direct refcounts are being used to utilize these new functions. In each location pass if event_mutex is locked or not. This allows us to drop events automatically in future patches clearly. Ensure when caller states the lock is held, it really is (or is not) held. Link: https://lkml.kernel.org/r/20230614163336.5797-3-beaub@linux.microsoft.com Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Store register flags on eventsBeau Belgrave
Currently we don't have any available flags for user processes to use to indicate options for user_events. We will soon have a flag to indicate the event should or should not auto-delete once it's not being used by anyone. Add a reg_flags field to user_events and parameters to existing functions to allow for this in future patches. Link: https://lkml.kernel.org/r/20230614163336.5797-2-beaub@linux.microsoft.com Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Remove user_ns walk for groupsBeau Belgrave
During discussions it was suggested that user_ns is not a good place to try to attach a tracing namespace. The current code has stubs to enable that work that are very likely to change and incur a performance cost. Remove the user_ns walk when creating a group and determining the system name to use, since it's unlikely user_ns will be used in the future. Link: https://lore.kernel.org/all/20230601-urenkel-holzofen-cd9403b9cadd@brauner/ Link: https://lore.kernel.org/linux-trace-kernel/20230601224928.301-1-beaub@linux.microsoft.com Suggested-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Fix the incorrect trace record for empty arguments eventssunliming
The user_events support events that has empty arguments. But the trace event is discarded and not really committed when the arguments is empty. Fix this by not attempting to copy in zero-length data. Link: https://lkml.kernel.org/r/20230606062027.1008398-2-sunliming@kylinos.cn Acked-by: Beau Belgrave <beaub@linux.microsoft.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: sunliming <sunliming@kylinos.cn> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing: Modify print_fields() for fields output ordersunliming
Now the print_fields() print trace event fields in reverse order. Modify it to the positive sequence. Example outputs for a user event: test0 u32 count1; u32 count2 Output before: example-2547 [000] ..... 325.666387: test0: count2=0x2 (2) count1=0x1 (1) Output after: example-2742 [002] ..... 429.769370: test0: count1=0x1 (1) count2=0x2 (2) Link: https://lore.kernel.org/linux-trace-kernel/20230525085232.5096-1-sunliming@kylinos.cn Fixes: 80a76994b2d88 ("tracing: Add "fields" option to show raw trace event fields") Signed-off-by: sunliming <sunliming@kylinos.cn> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Handle matching arguments that is null from dyn_eventssunliming
When A registering user event from dyn_events has no argments, it will pass the matching check, regardless of whether there is a user event with the same name and arguments. Add the matching check when the arguments of registering user event is null. Link: https://lore.kernel.org/linux-trace-kernel/20230529065110.303440-1-sunliming@kylinos.cn Signed-off-by: sunliming <sunliming@kylinos.cn> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Prevent same name but different args eventsunliming
User processes register name_args for events. If the same name but different args event are registered. The trace outputs of second event are printed as the first event. This is incorrect. Return EADDRINUSE back to the user process if the same name but different args event has being registered. Link: https://lore.kernel.org/linux-trace-kernel/20230529032100.286534-1-sunliming@kylinos.cn Signed-off-by: sunliming <sunliming@kylinos.cn> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13bpf: ensure main program has an extableKrister Johansen
When subprograms are in use, the main program is not jit'd after the subprograms because jit_subprogs sets a value for prog->bpf_func upon success. Subsequent calls to the JIT are bypassed when this value is non-NULL. This leads to a situation where the main program and its func[0] counterpart are both in the bpf kallsyms tree, but only func[0] has an extable. Extables are only created during JIT. Now there are two nearly identical program ksym entries in the tree, but only one has an extable. Depending upon how the entries are placed, there's a chance that a fault will call search_extable on the aux with the NULL entry. Since jit_subprogs already copies state from func[0] to the main program, include the extable pointer in this state duplication. Additionally, ensure that the copy of the main program in func[0] is not added to the bpf_prog_kallsyms table. Instead, let the main program get added later in bpf_prog_load(). This ensures there is only a single copy of the main program in the kallsyms table, and that its tag matches the tag observed by tooling like bpftool. Cc: stable@vger.kernel.org Fixes: 1c2a088a6626 ("bpf: x64: add JIT support for multi-function programs") Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> Link: https://lore.kernel.org/r/6de9b2f4b4724ef56efbb0339daaa66c8b68b1e7.1686616663.git.kjlx@templeofstupid.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-12Merge tag 'mm-hotfixes-stable-2023-06-12-12-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "19 hotfixes. 14 are cc:stable and the remainder address issues which were introduced during this development cycle or which were considered inappropriate for a backport" * tag 'mm-hotfixes-stable-2023-06-12-12-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: zswap: do not shrink if cgroup may not zswap page cache: fix page_cache_next/prev_miss off by one ocfs2: check new file size on fallocate call mailmap: add entry for John Keeping mm/damon/core: fix divide error in damon_nr_accesses_to_accesses_bp() epoll: ep_autoremove_wake_function should use list_del_init_careful mm/gup_test: fix ioctl fail for compat task nilfs2: reject devices with insufficient block count ocfs2: fix use-after-free when unmounting read-only filesystem lib/test_vmalloc.c: avoid garbage in page array nilfs2: fix possible out-of-bounds segment allocation in resize ioctl riscv/purgatory: remove PGO flags powerpc/purgatory: remove PGO flags x86/purgatory: remove PGO flags kexec: support purgatories with .text.hot sections mm/uffd: allow vma to merge as much as possible mm/uffd: fix vma operation where start addr cuts part of vma radix-tree: move declarations to header nilfs2: fix incomplete buffer cleanup in nilfs_btnode_abort_change_key()
2023-06-12kexec: support purgatories with .text.hot sectionsRicardo Ribalda
Patch series "kexec: Fix kexec_file_load for llvm16 with PGO", v7. When upreving llvm I realised that kexec stopped working on my test platform. The reason seems to be that due to PGO there are multiple .text sections on the purgatory, and kexec does not supports that. This patch (of 4): Clang16 links the purgatory text in two sections when PGO is in use: [ 1] .text PROGBITS 0000000000000000 00000040 00000000000011a1 0000000000000000 AX 0 0 16 [ 2] .rela.text RELA 0000000000000000 00003498 0000000000000648 0000000000000018 I 24 1 8 ... [17] .text.hot. PROGBITS 0000000000000000 00003220 000000000000020b 0000000000000000 AX 0 0 1 [18] .rela.text.hot. RELA 0000000000000000 00004428 0000000000000078 0000000000000018 I 24 17 8 And both of them have their range [sh_addr ... sh_addr+sh_size] on the area pointed by `e_entry`. This causes that image->start is calculated twice, once for .text and another time for .text.hot. The second calculation leaves image->start in a random location. Because of this, the system crashes immediately after: kexec_core: Starting new kernel Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-0-b05c520b7296@chromium.org Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-1-b05c520b7296@chromium.org Fixes: 930457057abe ("kernel/kexec_file.c: split up __kexec_load_puragory") Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> Reviewed-by: Ross Zwisler <zwisler@google.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Reviewed-by: Philipp Rudo <prudo@redhat.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Palmer Dabbelt <palmer@rivosinc.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Simon Horman <horms@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Rix <trix@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-12cgroup: Do not corrupt task iteration when rebinding subsystemXiu Jianfeng
We found a refcount UAF bug as follows: refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 342 at lib/refcount.c:25 refcount_warn_saturate+0xa0/0x148 Workqueue: events cpuset_hotplug_workfn Call trace: refcount_warn_saturate+0xa0/0x148 __refcount_add.constprop.0+0x5c/0x80 css_task_iter_advance_css_set+0xd8/0x210 css_task_iter_advance+0xa8/0x120 css_task_iter_next+0x94/0x158 update_tasks_root_domain+0x58/0x98 rebuild_root_domains+0xa0/0x1b0 rebuild_sched_domains_locked+0x144/0x188 cpuset_hotplug_workfn+0x138/0x5a0 process_one_work+0x1e8/0x448 worker_thread+0x228/0x3e0 kthread+0xe0/0xf0 ret_from_fork+0x10/0x20 then a kernel panic will be triggered as below: Unable to handle kernel paging request at virtual address 00000000c0000010 Call trace: cgroup_apply_control_disable+0xa4/0x16c rebind_subsystems+0x224/0x590 cgroup_destroy_root+0x64/0x2e0 css_free_rwork_fn+0x198/0x2a0 process_one_work+0x1d4/0x4bc worker_thread+0x158/0x410 kthread+0x108/0x13c ret_from_fork+0x10/0x18 The race that cause this bug can be shown as below: (hotplug cpu) | (umount cpuset) mutex_lock(&cpuset_mutex) | mutex_lock(&cgroup_mutex) cpuset_hotplug_workfn | rebuild_root_domains | rebind_subsystems update_tasks_root_domain | spin_lock_irq(&css_set_lock) css_task_iter_start | list_move_tail(&cset->e_cset_node[ss->id] while(css_task_iter_next) | &dcgrp->e_csets[ss->id]); css_task_iter_end | spin_unlock_irq(&css_set_lock) mutex_unlock(&cpuset_mutex) | mutex_unlock(&cgroup_mutex) Inside css_task_iter_start/next/end, css_set_lock is hold and then released, so when iterating task(left side), the css_set may be moved to another list(right side), then it->cset_head points to the old list head and it->cset_pos->next points to the head node of new list, which can't be used as struct css_set. To fix this issue, switch from all css_sets to only scgrp's css_sets to patch in-flight iterators to preserve correct iteration, and then update it->cset_head as well. Reported-by: Gaosheng Cui <cuigaosheng1@huawei.com> Link: https://www.spinics.net/lists/cgroups/msg37935.html Suggested-by: Michal Koutný <mkoutny@suse.com> Link: https://lore.kernel.org/all/20230526114139.70274-1-xiujianfeng@huaweicloud.com/ Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Fixes: 2d8f243a5e6e ("cgroup: implement cgroup->e_csets[]") Cc: stable@vger.kernel.org # v3.16+ Signed-off-by: Tejun Heo <tj@kernel.org>
2023-06-12cgroup,freezer: hold cpu_hotplug_lock before freezer_mutex in ↵Tetsuo Handa
freezer_css_{online,offline}() syzbot is again reporting circular locking dependency between cpu_hotplug_lock and freezer_mutex. Do like what we did with commit 57dcd64c7e036299 ("cgroup,freezer: hold cpu_hotplug_lock before freezer_mutex"). Reported-by: syzbot <syzbot+2ab700fe1829880a2ec6@syzkaller.appspotmail.com> Closes: https://syzkaller.appspot.com/bug?extid=2ab700fe1829880a2ec6 Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Tested-by: syzbot <syzbot+2ab700fe1829880a2ec6@syzkaller.appspotmail.com> Fixes: f5d39b020809 ("freezer,sched: Rewrite core freezer logic") Cc: stable@vger.kernel.org # v6.1+ Signed-off-by: Tejun Heo <tj@kernel.org>
2023-06-09Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio bug fixes from Michael Tsirkin: "A bunch of fixes all over the place" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: tools/virtio: use canonical ftrace path vhost_vdpa: support PACKED when setting-getting vring_base vhost: support PACKED when setting-getting vring_base vhost: Fix worker hangs due to missed wake up calls vhost: Fix crash during early vhost_transport_send_pkt calls vhost_net: revert upend_idx only on retriable error vhost_vdpa: tell vqs about the negotiated vdpa/mlx5: Fix hang when cvq commands are triggered during device unregister tools/virtio: Add .gitignore for ringtest tools/virtio: Fix arm64 ringtest compilation error vduse: avoid empty string for dev name vhost: use kzalloc() instead of kmalloc() followed by memset()
2023-06-08Merge tag 'cgroup-for-6.4-rc5-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: - Fix css_set reference leaks on fork failures - Fix CPU hotplug locking in cgroup_transfer_tasks() which is used by cgroup1 cpuset - Doc update * tag 'cgroup-for-6.4-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: Documentation: Clarify usage of memory limits cgroup: always put cset in cgroup_css_set_put_fork cgroup: fix missing cpus_read_{lock,unlock}() in cgroup_transfer_tasks()
2023-06-08vhost: Fix worker hangs due to missed wake up callsMike Christie
We can race where we have added work to the work_list, but vhost_task_fn has passed that check but not yet set us into TASK_INTERRUPTIBLE. wake_up_process will see us in TASK_RUNNING and just return. This bug was intoduced in commit f9010dbdce91 ("fork, vhost: Use CLONE_THREAD to fix freezer/ps regression") when I moved the setting of TASK_INTERRUPTIBLE to simplfy the code and avoid get_signal from logging warnings about being in the wrong state. This moves the setting of TASK_INTERRUPTIBLE back to before we test if we need to stop the task to avoid a possible race there as well. We then have vhost_worker set TASK_RUNNING if it finds work similar to before. Fixes: f9010dbdce91 ("fork, vhost: Use CLONE_THREAD to fix freezer/ps regression") Signed-off-by: Mike Christie <michael.christie@oracle.com> Message-Id: <20230607192338.6041-3-michael.christie@oracle.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-06-08Merge tag 'net-6.4-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from can, wifi, netfilter, bluetooth and ebpf. Current release - regressions: - bpf: sockmap: avoid potential NULL dereference in sk_psock_verdict_data_ready() - wifi: iwlwifi: fix -Warray-bounds bug in iwl_mvm_wait_d3_notif() - phylink: actually fix ksettings_set() ethtool call - eth: dwmac-qcom-ethqos: fix a regression on EMAC < 3 Current release - new code bugs: - wifi: mt76: fix possible NULL pointer dereference in mt7996_mac_write_txwi() Previous releases - regressions: - netfilter: fix NULL pointer dereference in nf_confirm_cthelper - wifi: rtw88/rtw89: correct PS calculation for SUPPORTS_DYNAMIC_PS - openvswitch: fix upcall counter access before allocation - bluetooth: - fix use-after-free in hci_remove_ltk/hci_remove_irk - fix l2cap_disconnect_req deadlock - nic: bnxt_en: prevent kernel panic when receiving unexpected PHC_UPDATE event Previous releases - always broken: - core: annotate rfs lockless accesses - sched: fq_pie: ensure reasonable TCA_FQ_PIE_QUANTUM values - netfilter: add null check for nla_nest_start_noflag() in nft_dump_basechain_hook() - bpf: fix UAF in task local storage - ipv4: ping_group_range: allow GID from 2147483648 to 4294967294 - ipv6: rpl: fix route of death. - tcp: gso: really support BIG TCP - mptcp: fixes for user-space PM address advertisement - smc: avoid to access invalid RMBs' MRs in SMCRv1 ADD LINK CONT - can: avoid possible use-after-free when j1939_can_rx_register fails - batman-adv: fix UaF while rescheduling delayed work - eth: qede: fix scheduling while atomic - eth: ice: make writes to /dev/gnssX synchronous" * tag 'net-6.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits) bnxt_en: Implement .set_port / .unset_port UDP tunnel callbacks bnxt_en: Prevent kernel panic when receiving unexpected PHC_UPDATE event bnxt_en: Skip firmware fatal error recovery if chip is not accessible bnxt_en: Query default VLAN before VNIC setup on a VF bnxt_en: Don't issue AP reset during ethtool's reset operation bnxt_en: Fix bnxt_hwrm_update_rss_hash_cfg() net: bcmgenet: Fix EEE implementation eth: ixgbe: fix the wake condition eth: bnxt: fix the wake condition lib: cpu_rmap: Fix potential use-after-free in irq_cpu_rmap_release() bpf: Add extra path pointer check to d_path helper net: sched: fix possible refcount leak in tc_chain_tmplt_add() net: sched: act_police: fix sparse errors in tcf_police_dump() net: openvswitch: fix upcall counter access before allocation net: sched: move rtm_tca_policy declaration to include file ice: make writes to /dev/gnssX synchronous net: sched: add rcu annotations around qdisc->qdisc_sleeping rfs: annotate lockless accesses to RFS sock flow table rfs: annotate lockless accesses to sk->sk_rxhash virtio_net: use control_buf for coalesce params ...
2023-06-08bpf: Fix verifier id tracking of scalars on spillMaxim Mikityanskiy
The following scenario describes a bug in the verifier where it incorrectly concludes about equivalent scalar IDs which could lead to verifier bypass in privileged mode: 1. Prepare a 32-bit rogue number. 2. Put the rogue number into the upper half of a 64-bit register, and roll a random (unknown to the verifier) bit in the lower half. The rest of the bits should be zero (although variations are possible). 3. Assign an ID to the register by MOVing it to another arbitrary register. 4. Perform a 32-bit spill of the register, then perform a 32-bit fill to another register. Due to a bug in the verifier, the ID will be preserved, although the new register will contain only the lower 32 bits, i.e. all zeros except one random bit. At this point there are two registers with different values but the same ID, which means the integrity of the verifier state has been corrupted. 5. Compare the new 32-bit register with 0. In the branch where it's equal to 0, the verifier will believe that the original 64-bit register is also 0, because it has the same ID, but its actual value still contains the rogue number in the upper half. Some optimizations of the verifier prevent the actual bypass, so extra care is needed: the comparison must be between two registers, and both branches must be reachable (this is why one random bit is needed). Both branches are still suitable for the bypass. 6. Right shift the original register by 32 bits to pop the rogue number. 7. Use the rogue number as an offset with any pointer. The verifier will believe that the offset is 0, while in reality it's the given number. The fix is similar to the 32-bit BPF_MOV handling in check_alu_op for SCALAR_VALUE. If the spill is narrowing the actual register value, don't keep the ID, make sure it's reset to 0. Fixes: 354e8f1970f8 ("bpf: Support <8-byte scalar spill and refill") Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Andrii Nakryiko <andrii@kernel.org> # Checked veristat delta Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20230607123951.558971-2-maxtram95@gmail.com
2023-06-07Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2023-06-07 We've added 7 non-merge commits during the last 7 day(s) which contain a total of 12 files changed, 112 insertions(+), 7 deletions(-). The main changes are: 1) Fix a use-after-free in BPF's task local storage, from KP Singh. 2) Make struct path handling more robust in bpf_d_path, from Jiri Olsa. 3) Fix a syzbot NULL-pointer dereference in sockmap, from Eric Dumazet. 4) UAPI fix for BPF_NETFILTER before final kernel ships, from Florian Westphal. 5) Fix map-in-map array_map_gen_lookup code generation where elem_size was not being set for inner maps, from Rhys Rustad-Elliott. 6) Fix sockopt_sk selftest's NETLINK_LIST_MEMBERSHIPS assertion, from Yonghong Song. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf: Add extra path pointer check to d_path helper selftests/bpf: Fix sockopt_sk selftest bpf: netfilter: Add BPF_NETFILTER bpf_attach_type selftests/bpf: Add access_inner_map selftest bpf: Fix elem_size not being set for inner maps bpf: Fix UAF in task local storage bpf, sockmap: Avoid potential NULL dereference in sk_psock_verdict_data_ready() ==================== Link: https://lore.kernel.org/r/20230607220514.29698-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-07bpf: Add extra path pointer check to d_path helperJiri Olsa
Anastasios reported crash on stable 5.15 kernel with following BPF attached to lsm hook: SEC("lsm.s/bprm_creds_for_exec") int BPF_PROG(bprm_creds_for_exec, struct linux_binprm *bprm) { struct path *path = &bprm->executable->f_path; char p[128] = { 0 }; bpf_d_path(path, p, 128); return 0; } But bprm->executable can be NULL, so bpf_d_path call will crash: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC NOPTI ... RIP: 0010:d_path+0x22/0x280 ... Call Trace: <TASK> bpf_d_path+0x21/0x60 bpf_prog_db9cf176e84498d9_bprm_creds_for_exec+0x94/0x99 bpf_trampoline_6442506293_0+0x55/0x1000 bpf_lsm_bprm_creds_for_exec+0x5/0x10 security_bprm_creds_for_exec+0x29/0x40 bprm_execve+0x1c1/0x900 do_execveat_common.isra.0+0x1af/0x260 __x64_sys_execve+0x32/0x40 It's problem for all stable trees with bpf_d_path helper, which was added in 5.9. This issue is fixed in current bpf code, where we identify and mark trusted pointers, so the above code would fail even to load. For the sake of the stable trees and to workaround potentially broken verifier in the future, adding the code that reads the path object from the passed pointer and verifies it's valid in kernel space. Fixes: 6e22ab9da793 ("bpf: Add d_path helper") Reported-by: Anastasios Papagiannis <tasos.papagiannnis@gmail.com> Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20230606181714.532998-1-jolsa@kernel.org
2023-06-05bpf: netfilter: Add BPF_NETFILTER bpf_attach_typeFlorian Westphal
Andrii Nakryiko writes: And we currently don't have an attach type for NETLINK BPF link. Thankfully it's not too late to add it. I see that link_create() in kernel/bpf/syscall.c just bypasses attach_type check. We shouldn't have done that. Instead we need to add BPF_NETLINK attach type to enum bpf_attach_type. And wire all that properly throughout the kernel and libbpf itself. This adds BPF_NETFILTER and uses it. This breaks uabi but this wasn't in any non-rc release yet, so it should be fine. v2: check link_attack prog type in link_create too Fixes: 84601d6ee68a ("bpf: add bpf_link support for BPF_NETFILTER programs") Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/CAEf4BzZ69YgrQW7DHCJUT_X+GqMq_ZQQPBwopaJJVGFD5=d5Vg@mail.gmail.com/ Link: https://lore.kernel.org/bpf/20230605131445.32016-1-fw@strlen.de
2023-06-03Merge tag 'probes-fixes-6.4-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes fixes from Masami Hiramatsu: - Return NULL if the trace_probe list on trace_probe_event is empty - selftests/ftrace: Choose testing symbol name for filtering feature from sample data instead of fixed symbol * tag 'probes-fixes-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: selftests/ftrace: Choose target function for filter test from samples tracing/probe: trace_probe_primary_from_call(): checked list_first_entry
2023-06-02bpf: Fix elem_size not being set for inner mapsRhys Rustad-Elliott
Commit d937bc3449fa ("bpf: make uniform use of array->elem_size everywhere in arraymap.c") changed array_map_gen_lookup to use array->elem_size instead of round_up(map->value_size, 8) as the element size when generating code to access a value in an array map. array->elem_size, however, is not set by bpf_map_meta_alloc when initializing an BPF_MAP_TYPE_ARRAY_OF_MAPS or BPF_MAP_TYPE_HASH_OF_MAPS. This results in array_map_gen_lookup incorrectly outputting code that always accesses index 0 in the array (as the index will be calculated via a multiplication with the element size, which is incorrectly set to 0). Set elem_size on the bpf_array object when allocating an array or hash of maps to fix this. Fixes: d937bc3449fa ("bpf: make uniform use of array->elem_size everywhere in arraymap.c") Signed-off-by: Rhys Rustad-Elliott <me@rhysre.net> Link: https://lore.kernel.org/r/20230602190110.47068-2-me@rhysre.net Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-06-02bpf: Fix UAF in task local storageKP Singh
When task local storage was generalized for tracing programs, the bpf_task_local_storage callback was moved from a BPF LSM hook callback for security_task_free LSM hook to it's own callback. But a failure case in bad_fork_cleanup_security was missed which, when triggered, led to a dangling task owner pointer and a subsequent use-after-free. Move the bpf_task_storage_free to the very end of free_task to handle all failure cases. This issue was noticed when a BPF LSM program was attached to the task_alloc hook on a kernel with KASAN enabled. The program used bpf_task_storage_get to copy the task local storage from the current task to the new task being created. Fixes: a10787e6d58c ("bpf: Enable task local storage for tracing programs") Reported-by: Kuba Piecuch <jpiecuch@google.com> Signed-off-by: KP Singh <kpsingh@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230602002612.1117381-1-kpsingh@kernel.org Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-06-01Merge tag 'modules-6.4-rc5-second-pull' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull modules fix from Luis Chamberlain: "A zstd fix by lucas as he tested zstd decompression support" * tag 'modules-6.4-rc5-second-pull' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: module/decompress: Fix error checking on zstd decompression
2023-06-01module/decompress: Fix error checking on zstd decompressionLucas De Marchi
While implementing support for in-kernel decompression in kmod, finit_module() was returning a very suspicious value: finit_module(3, "", MODULE_INIT_COMPRESSED_FILE) = 18446744072717407296 It turns out the check for module_get_next_page() failing is wrong, and hence the decompression was not really taking place. Invert the condition to fix it. Fixes: 169a58ad824d ("module/decompress: Support zstd in-kernel decompression") Cc: stable@kernel.org Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-06-01fork, vhost: Use CLONE_THREAD to fix freezer/ps regressionMike Christie
When switching from kthreads to vhost_tasks two bugs were added: 1. The vhost worker tasks's now show up as processes so scripts doing ps or ps a would not incorrectly detect the vhost task as another process. 2. kthreads disabled freeze by setting PF_NOFREEZE, but vhost tasks's didn't disable or add support for them. To fix both bugs, this switches the vhost task to be thread in the process that does the VHOST_SET_OWNER ioctl, and has vhost_worker call get_signal to support SIGKILL/SIGSTOP and freeze signals. Note that SIGKILL/STOP support is required because CLONE_THREAD requires CLONE_SIGHAND which requires those 2 signals to be supported. This is a modified version of the patch written by Mike Christie <michael.christie@oracle.com> which was a modified version of patch originally written by Linus. Much of what depended upon PF_IO_WORKER now depends on PF_USER_WORKER. Including ignoring signals, setting up the register state, and having get_signal return instead of calling do_group_exit. Tidied up the vhost_task abstraction so that the definition of vhost_task only needs to be visible inside of vhost_task.c. Making it easier to review the code and tell what needs to be done where. As part of this the main loop has been moved from vhost_worker into vhost_task_fn. vhost_worker now returns true if work was done. The main loop has been updated to call get_signal which handles SIGSTOP, freezing, and collects the message that tells the thread to exit as part of process exit. This collection clears __fatal_signal_pending. This collection is not guaranteed to clear signal_pending() so clear that explicitly so the schedule() sleeps. For now the vhost thread continues to exist and run work until the last file descriptor is closed and the release function is called as part of freeing struct file. To avoid hangs in the coredump rendezvous and when killing threads in a multi-threaded exec. The coredump code and de_thread have been modified to ignore vhost threads. Remvoing the special case for exec appears to require teaching vhost_dev_flush how to directly complete transactions in case the vhost thread is no longer running. Removing the special case for coredump rendezvous requires either the above fix needed for exec or moving the coredump rendezvous into get_signal. Fixes: 6e890c5d5021 ("vhost: use vhost_tasks for worker threads") Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Co-developed-by: Mike Christie <michael.christie@oracle.com> Signed-off-by: Mike Christie <michael.christie@oracle.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-05-31tracing/probe: trace_probe_primary_from_call(): checked list_first_entryPietro Borrello
All callers of trace_probe_primary_from_call() check the return value to be non NULL. However, the function returns list_first_entry(&tpe->probes, ...) which can never be NULL. Additionally, it does not check for the list being possibly empty, possibly causing a type confusion on empty lists. Use list_first_entry_or_null() which solves both problems. Link: https://lore.kernel.org/linux-trace-kernel/20230128-list-entry-null-check-v1-1-8bde6a3da2ef@diag.uniroma1.it/ Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") Signed-off-by: Pietro Borrello <borrello@diag.uniroma1.it> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Mukesh Ojha <quic_mojha@quicinc.com> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-30Merge tag 'modules-6.4-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull modules fix from Luis Chamberlain: "A fix is provided for ia64. Even though ia64 is on life support it helps to fix issues if we can. Thanks to Linus for doing tons of the ia64 debugging" * tag 'modules-6.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: module: fix module load for ia64
2023-05-30module: fix module load for ia64Song Liu
Frank reported boot regression in ia64 as: ELILO v3.16 for EFI/IA-64 .. Uncompressing Linux... done Loading file AC100221.initrd.img...done [ 0.000000] Linux version 6.4.0-rc3 (root@x4270) (ia64-linux-gcc (GCC) 12.2.0, GNU ld (GNU Binutils) 2.39) #1 SMP Thu May 25 15:52:20 CEST 2023 [ 0.000000] efi: EFI v1.1 by HP [ 0.000000] efi: SALsystab=0x3ee7a000 ACPI 2.0=0x3fe2a000 ESI=0x3ee7b000 SMBIOS=0x3ee7c000 HCDP=0x3fe28000 [ 0.000000] PCDP: v3 at 0x3fe28000 [ 0.000000] earlycon: uart8250 at MMIO 0x00000000f4050000 (options '9600n8') [ 0.000000] printk: bootconsole [uart8250] enabled [ 0.000000] ACPI: Early table checksum verification disabled [ 0.000000] ACPI: RSDP 0x000000003FE2A000 000028 (v02 HP ) [ 0.000000] ACPI: XSDT 0x000000003FE2A02C 0000CC (v01 HP rx2620 00000000 HP 00000000) [...] [ 3.793350] Run /init as init process Loading, please wait... Starting systemd-udevd version 252.6-1 [ 3.951100] ------------[ cut here ]------------ [ 3.951100] WARNING: CPU: 6 PID: 140 at kernel/module/main.c:1547 __layout_sections+0x370/0x3c0 [ 3.949512] Unable to handle kernel paging request at virtual address 1000000000000000 [ 3.951100] Modules linked in: [ 3.951100] CPU: 6 PID: 140 Comm: (udev-worker) Not tainted 6.4.0-rc3 #1 [ 3.956161] (udev-worker)[142]: Oops 11003706212352 [1] [ 3.951774] Hardware name: hp server rx2620 , BIOS 04.29 11/30/2007 [ 3.951774] [ 3.951774] Call Trace: [ 3.958339] Unable to handle kernel paging request at virtual address 1000000000000000 [ 3.956161] Modules linked in: [ 3.951774] [<a0000001000156d0>] show_stack.part.0+0x30/0x60 [ 3.951774] sp=e000000183a67b20 bsp=e000000183a61628 [ 3.956161] [ 3.956161] which bisect to module_memory change [1]. Debug showed that ia64 uses some special sections: __layout_sections: section .got (sh_flags 10000002) matched to MOD_INVALID __layout_sections: section .sdata (sh_flags 10000003) matched to MOD_INVALID __layout_sections: section .sbss (sh_flags 10000003) matched to MOD_INVALID All these sections are loaded to module core memory before [1]. Fix ia64 boot by loading these sections to MOD_DATA (core rw data). [1] commit ac3b43283923 ("module: replace module_layout with module_memory") Fixes: ac3b43283923 ("module: replace module_layout with module_memory") Reported-by: Frank Scheiner <frank.scheiner@web.de> Closes: https://lists.debian.org/debian-ia64/2023/05/msg00010.html Closes: https://marc.info/?l=linux-ia64&m=168509859125505 Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Song Liu <song@kernel.org> Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-05-29Merge tag 'trace-v6.4-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: "User events: - Use long instead of int for storing the enable set/clear bit, as it was found that big endian machines could end up using the wrong bits. - Split allocating mm and attaching it. This keeps the allocation separate from the registration and avoids various races. - Remove RCU locking around pin_user_pages_remote() as that can schedule. The RCU protection is no longer needed with the above split of mm allocation and attaching. - Rename the "link" fields of the various structs to something more meaningful. - Add comments around user_event_mm struct usage and locking requirements. Timerlat tracer: - Fix missed wakeup of timerlat thread caused by the timerlat interrupt triggering when tracing is off. The timer interrupt handler needs to always wake up the timerlat thread regardless if tracing is enabled or not, otherwise, it will never wake up. Histograms: - Fix regression of breaking the "stacktrace" modifier for variables. That modifier cannot be used for values, but can be used for variables that are passed from one histogram to the next. This was broken when adding the restriction to values as the variable logic used the same code. - Rename the special field "stacktrace" to "common_stacktrace". Special fields (that are not actually part of the event, but can act just like event fields, like 'comm' and 'timestamp') should be prefixed with 'common_' for consistency. To keep backward compatibility, 'stacktrace' can still be used (as with the special field 'cpu'), but can be overridden if the event has a field called 'stacktrace'. - Update the synthetic event selftests to use the new name (synthetic events are created by histograms) Tracing bootup selftests: - Reorganize the code to keep artifacts of the selftests not compiled in when selftests are not configured. - Add various cond_resched() around the selftest code, as the softlock watchdog was triggering much more often. It appears that the kernel runs slower now with full debugging enabled. - While debugging ftrace with ftrace (using an instance ring buffer instead of the top level one), I found that the selftests were disabling prints to the debug instance. This should not happen, as the selftests only disable printing to the main buffer as the selftests examine the main buffer to see if it has what it expects, and prints can make the tests fail. Make the selftests only disable printing to the toplevel buffer, and leave the instance buffers alone" * tag 'trace-v6.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Have function_graph selftest call cond_resched() tracing: Only make selftest conditionals affect the global_trace tracing: Make tracing_selftest_running/delete nops when not used tracing: Have tracer selftests call cond_resched() before running tracing: Move setting of tracing_selftest_running out of register_tracer() tracing/selftests: Update synthetic event selftest to use common_stacktrace tracing: Rename stacktrace field to common_stacktrace tracing/histograms: Allow variables to have some modifiers tracing/user_events: Document user_event_mm one-shot list usage tracing/user_events: Rename link fields for clarity tracing/user_events: Remove RCU lock while pinning pages tracing/user_events: Split up mm alloc and attach tracing/timerlat: Always wakeup the timerlat thread tracing/user_events: Use long vs int for atomic bit ops
2023-05-29Revert "module: error out early on concurrent load of the same module file"Linus Torvalds
This reverts commit 9828ed3f695a138f7add89fa2a186ababceb8006. Sadly, it does seem to cause failures to load modules. Johan Hovold reports: "This change breaks module loading during boot on the Lenovo Thinkpad X13s (aarch64). Specifically it results in indefinite probe deferral of the display and USB (ethernet) which makes it a pain to debug. Typing in the dark to acquire some logs reveals that other modules are missing as well" Since this was applied late as a "let's try this", I'm reverting it asap, and we can try to figure out what goes wrong later. The excessive parallel module loading problem is annoying, but not noticeable in normal situations, and this was only meant as an optimistic workaround for a user-space bug. One possible solution may be to do the optimistic exclusive open first, and then use a lock to serialize loading if that fails. Reported-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/lkml/ZHRpH-JXAxA6DnzR@hovoldconsulting.com/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-05-28tracing: Have function_graph selftest call cond_resched()Steven Rostedt (Google)
When all kernel debugging is enabled (lockdep, KSAN, etc), the function graph enabling and disabling can take several seconds to complete. The function_graph selftest enables and disables function graph tracing several times. With full debugging enabled, the soft lockup watchdog was triggering because the selftest was running without ever scheduling. Add cond_resched() throughout the test to make sure it does not trigger the soft lockup detector. Link: https://lkml.kernel.org/r/20230528051742.1325503-6-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28tracing: Only make selftest conditionals affect the global_traceSteven Rostedt (Google)
The tracing_selftest_running and tracing_selftest_disabled variables were to keep trace_printk() and other writes from affecting the tracing selftests, as the tracing selftests would examine the ring buffer to see if it contained what it expected or not. trace_printk() and friends could add to the ring buffer and cause the selftests to fail (and then disable the tracer that was being tested). To keep that from happening, these variables were added and would keep trace_printk() and friends from writing to the ring buffer while the tests were going on. But this was only the top level ring buffer (owned by the global_trace instance). There is no reason to prevent writing into ring buffers of other instances via the trace_array_printk() and friends. For the functions that could be used by other instances, check if the global_trace is the tracer instance that is being written to before deciding to not allow the write. Link: https://lkml.kernel.org/r/20230528051742.1325503-5-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28tracing: Make tracing_selftest_running/delete nops when not usedSteven Rostedt (Google)
There's no reason to test the condition variables tracing_selftest_running or tracing_selftest_delete when tracing selftests are not enabled. Make them define 0s when not the selftests are not configured in. Link: https://lkml.kernel.org/r/20230528051742.1325503-4-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28tracing: Have tracer selftests call cond_resched() before runningSteven Rostedt (Google)
As there are more and more internal selftests being added to the Linux kernel (KSAN, lockdep, etc) the selftests are taking longer to run when these are enabled. Add a cond_resched() to the calling of do_run_tracer_selftest() to force a schedule if NEED_RESCHED is set, otherwise the soft lockup watchdog may trigger on boot up. Link: https://lkml.kernel.org/r/20230528051742.1325503-3-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28tracing: Move setting of tracing_selftest_running out of register_tracer()Steven Rostedt (Google)
The variables tracing_selftest_running and tracing_selftest_disabled are only used for when CONFIG_FTRACE_STARTUP_TEST is enabled. Make them only visible within the selftest code. The setting of those variables are in the register_tracer() call, and set in a location where they do not need to be. Create a wrapper around run_tracer_selftest() called do_run_tracer_selftest() which sets those variables, and have register_tracer() call that instead. Having those variables only set within the CONFIG_FTRACE_STARTUP_TEST scope gets rid of them (and also the ability to remove testing against them) when the startup tests are not enabled (most cases). Link: https://lkml.kernel.org/r/20230528051742.1325503-2-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28Merge tag 'core-debugobjects-2023-05-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull debugobjects fixes from Thomas Gleixner: "Two fixes for debugobjects: - Prevent the allocation path from waking up kswapd. That's a long standing issue due to the GFP_ATOMIC allocation flag. As debug objects can be invoked from pretty much any context waking kswapd can end up in arbitrary lock chains versus the waitqueue lock - Correct the explicit lockdep wait-type violation in debug_object_fill_pool()" * tag 'core-debugobjects-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: debugobjects: Don't wake up kswapd from fill_pool() debugobjects,locking: Annotate debug_object_fill_pool() wait type violation
2023-05-27Merge tag 'for-linus-6.4-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - a double free fix in the Xen pvcalls backend driver - a fix for a regression causing the MSI related sysfs entries to not being created in Xen PV guests - a fix in the Xen blkfront driver for handling insane input data better * tag 'for-linus-6.4-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/pci/xen: populate MSI sysfs entries xen/pvcalls-back: fix double frees with pvcalls_new_active_socket() xen/blkfront: Only check REQ_FUA for writes
2023-05-25module: error out early on concurrent load of the same module fileLinus Torvalds
It turns out that udev under certain circumstances will concurrently try to load the same modules over-and-over excessively. This isn't a kernel bug, but it ends up affecting the kernel, to the point that under certain circumstances we can fail to boot, because the kernel uses a lot of memory to read all the module data all at once. Note that it isn't a memory leak, it's just basically a thundering herd problem happening at bootup with a lot of CPUs, with the worst cases then being pretty bad. Admittedly the worst situations are somewhat contrived: lots and lots of CPUs, not a lot of memory, and KASAN enabled to make it all slower and as such (unintentionally) exacerbate the problem. Luis explains: [1] "My best assessment of the situation is that each CPU in udev ends up triggering a load of duplicate set of modules, not just one, but *a lot*. Not sure what heuristics udev uses to load a set of modules per CPU." Petr Pavlu chimes in: [2] "My understanding is that udev workers are forked. An initial kmod context is created by the main udevd process but no sharing happens after the fork. It means that the mentioned memory pool logic doesn't really kick in. Multiple parallel load requests come from multiple udev workers, for instance, each handling an udev event for one CPU device and making the exactly same requests as all others are doing at the same time. The optimization idea would be to recognize these duplicate requests at the udevd/kmod level and converge them" Note that module loading has tried to mitigate this issue before, see for example commit 064f4536d139 ("module: avoid allocation if module is already present and ready"), which has a few ASCII graphs on memory use due to this same issue. However, while that noticed that the module was already loaded, and exited with an error early before spending any more time on setting up the module, it didn't handle the case of multiple concurrent module loads all being active - but not complete - at the same time. Yes, one of them will eventually win the race and finalize its copy, and the others will then notice that the module already exists and error out, but while this all happens, we have tons of unnecessary concurrent work being done. Again, the real fix is for udev to not do that (maybe it should use threads instead of fork, and have actual shared data structures and not cause duplicate work). That real fix is apparently not trivial. But it turns out that the kernel already has a pretty good model for dealing with concurrent access to the same file: the i_writecount of the inode. In fact, the module loading already indirectly uses 'i_writecount' , because 'kernel_file_read()' will in fact do ret = deny_write_access(file); if (ret) return ret; ... allow_write_access(file); around the read of the file data. We do not allow concurrent writes to the file, and return -ETXTBUSY if the file was open for writing at the same time as the module data is loaded from it. And the solution to the reader concurrency problem is to simply extend this "no concurrent writers" logic to simply be "exclusive access". Note that "exclusive" in this context isn't really some absolute thing: it's only exclusion from writers and from other "special readers" that do this writer denial. So we simply introduce a variation of that "deny_write_access()" logic that not only denies write access, but also requires that this is the _only_ such access that denies write access. Which means that you can't start loading a module that is already being loaded as a module by somebody else, or you will get the same -ETXTBSY error that you would get if there were writers around. [ It also means that you can't try to load a currently executing executable as a module, for the same reason: executables do that same "deny_write_access()" thing, and that's obviously where the whole ETXTBSY logic traditionally came from. This is not a problem for kernel modules, since the set of normal executable files and kernel module files is entirely disjoint. ] This new function is called "exclusive_deny_write_access()", and the implementation is trivial, in that it's just an atomic decrement of i_writecount if it was 0 before. To use that new exclusivity check, all we then do is wrap the module loading with that exclusive_deny_write_access()() / allow_write_access() pair. The actual patch is a bit bigger than that, because we want to surround not just the "load file data" part, but the whole module setup, to get maximum exclusion. So this ends up splitting up "finit_module()" into a few helper functions to make it all very clear and legible. In Luis' test-case (bringing up 255 vcpu's in a virtual machine [3]), the "wasted vmalloc" space (ie module data read into a vmalloc'ed area in order to be loaded as a module, but then discarded because somebody else loaded the same module instead) dropped from 1.8GiB to 474kB. Yes, that's gigabytes to kilobytes. It doesn't drop completely to zero, because even with this change, you can still end up having completely serial pointless module loads, where one udev process has loaded a module fully (and thus the kernel has released that exclusive lock on the module file), and then another udev process tries to load the same module again. So while we cannot fully get rid of the fundamental bug in user space, we _can_ get rid of the excessive concurrent thundering herd effect. A couple of final side notes on this all: - This tweak only affects the "finit_module()" system call, which gives the kernel a file descriptor with the module data. You can also just feed the module data as raw data from user space with "init_module()" (note the lack of 'f' at the beginning), and obviously for that case we do _not_ have any "exclusive read" logic. So if you absolutely want to do things wrong in user space, and try to load the same module multiple times, and error out only later when the kernel ends up saying "you can't load the same module name twice", you can still do that. And in fact, some distros will do exactly that, because they will uncompress the kernel module data in user space before feeding it to the kernel (mainly because they haven't started using the new kernel side decompression yet). So this is not some absolute "you can't do concurrent loads of the same module". It's literally just a very simple heuristic that will catch it early in case you try to load the exact same module file at the same time, and in that case avoid a potentially nasty situation. - There is another user of "deny_write_access()": the verity code that enables fs-verity on a file (the FS_IOC_ENABLE_VERITY ioctl). If you use fs-verity and you care about verifying the kernel modules (which does make sense), you should do it *before* loading said kernel module. That may sound obvious, but now the implementation basically requires it. Because if you try to do it concurrently, the kernel may refuse to load the module file that is being set up by the fs-verity code. - This all will obviously mean that if you insist on loading the same module in parallel, only one module load will succeed, and the others will return with an error. That was true before too, but what is different is that the -ETXTBSY error can be returned *before* the success case of another process fully loading and instantiating the module. Again, that might sound obvious, and it is indeed the whole point of the whole change: we are much quicker to notice the whole "you're already in the process of loading this module". So it's very much intentional, but it does mean that if you just spray the kernel with "finit_module()", and expect that the module is immediately loaded afterwards without checking the return value, you are doing something horribly horribly wrong. I'd like to say that that would never happen, but the whole _reason_ for this commit is that udev is currently doing something horribly horribly wrong, so ... Link: https://lore.kernel.org/all/ZEGopJ8VAYnE7LQ2@bombadil.infradead.org/ [1] Link: https://lore.kernel.org/all/23bd0ce6-ef78-1cd8-1f21-0e706a00424a@suse.com/ [2] Link: https://lore.kernel.org/lkml/ZG%2Fa+nrt4%2FAAUi5z@bombadil.infradead.org/ [3] Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Lucas De Marchi <lucas.demarchi@intel.com> Cc: Petr Pavlu <petr.pavlu@suse.com> Tested-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-05-25Merge tag 'net-6.4-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from bluetooth and bpf. Current release - regressions: - net: fix skb leak in __skb_tstamp_tx() - eth: mtk_eth_soc: fix QoS on DSA MAC on non MTK_NETSYS_V2 SoCs Current release - new code bugs: - handshake: - fix sock->file allocation - fix handshake_dup() ref counting - bluetooth: - fix potential double free caused by hci_conn_unlink - fix UAF in hci_conn_hash_flush Previous releases - regressions: - core: fix stack overflow when LRO is disabled for virtual interfaces - tls: fix strparser rx issues - bpf: - fix many sockmap/TCP related issues - fix a memory leak in the LRU and LRU_PERCPU hash maps - init the offload table earlier - eth: mlx5e: - do as little as possible in napi poll when budget is 0 - fix using eswitch mapping in nic mode - fix deadlock in tc route query code Previous releases - always broken: - udplite: fix NULL pointer dereference in __sk_mem_raise_allocated() - raw: fix output xfrm lookup wrt protocol - smc: reset connection when trying to use SMCRv2 fails - phy: mscc: enable VSC8501/2 RGMII RX clock - eth: octeontx2-pf: fix TSOv6 offload - eth: cdc_ncm: deal with too low values of dwNtbOutMaxSize" * tag 'net-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (79 commits) udplite: Fix NULL pointer dereference in __sk_mem_raise_allocated(). net: phy: mscc: enable VSC8501/2 RGMII RX clock net: phy: mscc: remove unnecessary phydev locking net: phy: mscc: add support for VSC8501 net: phy: mscc: add VSC8502 to MODULE_DEVICE_TABLE net/handshake: Enable the SNI extension to work properly net/handshake: Unpin sock->file if a handshake is cancelled net/handshake: handshake_genl_notify() shouldn't ignore @flags net/handshake: Fix uninitialized local variable net/handshake: Fix handshake_dup() ref counting net/handshake: Remove unneeded check from handshake_dup() ipv6: Fix out-of-bounds access in ipv6_find_tlv() net: ethernet: mtk_eth_soc: fix QoS on DSA MAC on non MTK_NETSYS_V2 SoCs docs: netdev: document the existence of the mail bot net: fix skb leak in __skb_tstamp_tx() r8169: Use a raw_spinlock_t for the register locks. page_pool: fix inconsistency for page_pool_ring_[un]lock() bpf, sockmap: Test progs verifier error with latest clang bpf, sockmap: Test FIONREAD returns correct bytes in rx buffer with drops bpf, sockmap: Test FIONREAD returns correct bytes in rx buffer ...