diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/mm.h | 7 | ||||
| -rw-r--r-- | include/linux/userfaultfd_k.h | 3 | ||||
| -rw-r--r-- | include/trace/events/mmflags.h | 7 | ||||
| -rw-r--r-- | include/uapi/linux/mman.h | 1 | ||||
| -rw-r--r-- | include/uapi/linux/random.h | 17 | ||||
| -rw-r--r-- | include/vdso/datapage.h | 11 | ||||
| -rw-r--r-- | include/vdso/getrandom.h | 46 |
7 files changed, 91 insertions, 1 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 7d044e737dba..aa4fccb2a693 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -407,6 +407,13 @@ extern unsigned int kobjsize(const void *objp); #endif #ifdef CONFIG_64BIT +#define VM_DROPPABLE_BIT 40 +#define VM_DROPPABLE BIT(VM_DROPPABLE_BIT) +#else +#define VM_DROPPABLE VM_NONE +#endif + +#ifdef CONFIG_64BIT /* VM is sealed, in vm_flags */ #define VM_SEALED _BITUL(63) #endif diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index 05d59f74fc88..a12bcf042551 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -218,6 +218,9 @@ static inline bool vma_can_userfault(struct vm_area_struct *vma, { vm_flags &= __VM_UFFD_FLAGS; + if (vm_flags & VM_DROPPABLE) + return false; + if ((vm_flags & VM_UFFD_MINOR) && (!is_vm_hugetlb_page(vma) && !vma_is_shmem(vma))) return false; diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h index e46d6e82765e..b63d211bd141 100644 --- a/include/trace/events/mmflags.h +++ b/include/trace/events/mmflags.h @@ -165,6 +165,12 @@ IF_HAVE_PG_ARCH_X(arch_3) # define IF_HAVE_UFFD_MINOR(flag, name) #endif +#ifdef CONFIG_64BIT +# define IF_HAVE_VM_DROPPABLE(flag, name) {flag, name}, +#else +# define IF_HAVE_VM_DROPPABLE(flag, name) +#endif + #define __def_vmaflag_names \ {VM_READ, "read" }, \ {VM_WRITE, "write" }, \ @@ -197,6 +203,7 @@ IF_HAVE_VM_SOFTDIRTY(VM_SOFTDIRTY, "softdirty" ) \ {VM_MIXEDMAP, "mixedmap" }, \ {VM_HUGEPAGE, "hugepage" }, \ {VM_NOHUGEPAGE, "nohugepage" }, \ +IF_HAVE_VM_DROPPABLE(VM_DROPPABLE, "droppable" ) \ {VM_MERGEABLE, "mergeable" } \ #define show_vma_flags(flags) \ diff --git a/include/uapi/linux/mman.h b/include/uapi/linux/mman.h index a246e11988d5..e89d00528f2f 100644 --- a/include/uapi/linux/mman.h +++ b/include/uapi/linux/mman.h @@ -17,6 +17,7 @@ #define MAP_SHARED 0x01 /* Share changes */ #define MAP_PRIVATE 0x02 /* Changes are private */ #define MAP_SHARED_VALIDATE 0x03 /* share + validate extension flags */ +#define MAP_DROPPABLE 0x08 /* Zero memory under memory pressure. */ /* * Huge page size encoding when MAP_HUGETLB is specified, and a huge page diff --git a/include/uapi/linux/random.h b/include/uapi/linux/random.h index e744c23582eb..1dd047ec98a1 100644 --- a/include/uapi/linux/random.h +++ b/include/uapi/linux/random.h @@ -20,7 +20,7 @@ /* Add to (or subtract from) the entropy count. (Superuser only.) */ #define RNDADDTOENTCNT _IOW( 'R', 0x01, int ) -/* Get the contents of the entropy pool. (Superuser only.) */ +/* Get the contents of the entropy pool. (Superuser only.) (Removed in 2.6.9-rc2.) */ #define RNDGETPOOL _IOR( 'R', 0x02, int [2] ) /* @@ -55,4 +55,19 @@ struct rand_pool_info { #define GRND_RANDOM 0x0002 #define GRND_INSECURE 0x0004 +/** + * struct vgetrandom_opaque_params - arguments for allocating memory for vgetrandom + * + * @size_per_opaque_state: Size of each state that is to be passed to vgetrandom(). + * @mmap_prot: Value of the prot argument in mmap(2). + * @mmap_flags: Value of the flags argument in mmap(2). + * @reserved: Reserved for future use. + */ +struct vgetrandom_opaque_params { + __u32 size_of_opaque_state; + __u32 mmap_prot; + __u32 mmap_flags; + __u32 reserved[13]; +}; + #endif /* _UAPI_LINUX_RANDOM_H */ diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h index 7647e0946f50..b85f24cac3f5 100644 --- a/include/vdso/datapage.h +++ b/include/vdso/datapage.h @@ -117,6 +117,16 @@ struct vdso_data { struct arch_vdso_data arch_data; }; +/** + * struct vdso_rng_data - vdso RNG state information + * @generation: counter representing the number of RNG reseeds + * @is_ready: boolean signaling whether the RNG is initialized + */ +struct vdso_rng_data { + u64 generation; + u8 is_ready; +}; + /* * We use the hidden visibility to prevent the compiler from generating a GOT * relocation. Not only is going through a GOT useless (the entry couldn't and @@ -128,6 +138,7 @@ struct vdso_data { */ extern struct vdso_data _vdso_data[CS_BASES] __attribute__((visibility("hidden"))); extern struct vdso_data _timens_data[CS_BASES] __attribute__((visibility("hidden"))); +extern struct vdso_rng_data _vdso_rng_data __attribute__((visibility("hidden"))); /** * union vdso_data_store - Generic vDSO data page diff --git a/include/vdso/getrandom.h b/include/vdso/getrandom.h new file mode 100644 index 000000000000..a8b7c14b0ae0 --- /dev/null +++ b/include/vdso/getrandom.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2022-2024 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. + */ + +#ifndef _VDSO_GETRANDOM_H +#define _VDSO_GETRANDOM_H + +#include <linux/types.h> + +#define CHACHA_KEY_SIZE 32 +#define CHACHA_BLOCK_SIZE 64 + +/** + * struct vgetrandom_state - State used by vDSO getrandom(). + * + * @batch: One and a half ChaCha20 blocks of buffered RNG output. + * + * @key: Key to be used for generating next batch. + * + * @batch_key: Union of the prior two members, which is exactly two full + * ChaCha20 blocks in size, so that @batch and @key can be filled + * together. + * + * @generation: Snapshot of @rng_info->generation in the vDSO data page at + * the time @key was generated. + * + * @pos: Offset into @batch of the next available random byte. + * + * @in_use: Reentrancy guard for reusing a state within the same thread + * due to signal handlers. + */ +struct vgetrandom_state { + union { + struct { + u8 batch[CHACHA_BLOCK_SIZE * 3 / 2]; + u32 key[CHACHA_KEY_SIZE / sizeof(u32)]; + }; + u8 batch_key[CHACHA_BLOCK_SIZE * 2]; + }; + u64 generation; + u8 pos; + bool in_use; +}; + +#endif /* _VDSO_GETRANDOM_H */ |