summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/arm64/include/asm/processor.h38
-rw-r--r--arch/arm64/kernel/fpsimd.c47
-rw-r--r--arch/arm64/kernel/process.c6
-rw-r--r--arch/arm64/kernel/ptrace.c30
-rw-r--r--arch/arm64/kernel/signal.c3
-rw-r--r--arch/arm64/kernel/signal32.c3
-rw-r--r--arch/arm64/kernel/sys_compat.c2
7 files changed, 72 insertions, 57 deletions
diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 63d3850db224..767598932549 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -34,6 +34,8 @@
#ifdef __KERNEL__
+#include <linux/build_bug.h>
+#include <linux/stddef.h>
#include <linux/string.h>
#include <asm/alternative.h>
@@ -103,11 +105,18 @@ struct cpu_context {
struct thread_struct {
struct cpu_context cpu_context; /* cpu context */
- unsigned long tp_value; /* TLS register */
-#ifdef CONFIG_COMPAT
- unsigned long tp2_value;
-#endif
- struct user_fpsimd_state fpsimd_state;
+
+ /*
+ * Whitelisted fields for hardened usercopy:
+ * Maintainers must ensure manually that this contains no
+ * implicit padding.
+ */
+ struct {
+ unsigned long tp_value; /* TLS register */
+ unsigned long tp2_value;
+ struct user_fpsimd_state fpsimd_state;
+ } uw;
+
unsigned int fpsimd_cpu;
void *sve_state; /* SVE registers, if any */
unsigned int sve_vl; /* SVE vector length */
@@ -117,14 +126,17 @@ struct thread_struct {
struct debug_info debug; /* debugging */
};
-/*
- * Everything usercopied to/from thread_struct is statically-sized, so
- * no hardened usercopy whitelist is needed.
- */
static inline void arch_thread_struct_whitelist(unsigned long *offset,
unsigned long *size)
{
- *offset = *size = 0;
+ /* Verify that there is no padding among the whitelisted fields: */
+ BUILD_BUG_ON(sizeof_field(struct thread_struct, uw) !=
+ sizeof_field(struct thread_struct, uw.tp_value) +
+ sizeof_field(struct thread_struct, uw.tp2_value) +
+ sizeof_field(struct thread_struct, uw.fpsimd_state));
+
+ *offset = offsetof(struct thread_struct, uw);
+ *size = sizeof_field(struct thread_struct, uw);
}
#ifdef CONFIG_COMPAT
@@ -132,13 +144,13 @@ static inline void arch_thread_struct_whitelist(unsigned long *offset,
({ \
unsigned long *__tls; \
if (is_compat_thread(task_thread_info(t))) \
- __tls = &(t)->thread.tp2_value; \
+ __tls = &(t)->thread.uw.tp2_value; \
else \
- __tls = &(t)->thread.tp_value; \
+ __tls = &(t)->thread.uw.tp_value; \
__tls; \
})
#else
-#define task_user_tls(t) (&(t)->thread.tp_value)
+#define task_user_tls(t) (&(t)->thread.uw.tp_value)
#endif
/* Sync TPIDR_EL0 back to thread_struct for current */
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index b13a9b4dd13b..87a35364e750 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -224,7 +224,7 @@ static void sve_user_enable(void)
* sets TIF_SVE.
*
* When stored, FPSIMD registers V0-V31 are encoded in
- * task->fpsimd_state; bits [max : 128] for each of Z0-Z31 are
+ * task->thread.uw.fpsimd_state; bits [max : 128] for each of Z0-Z31 are
* logically zero but not stored anywhere; P0-P15 and FFR are not
* stored and have unspecified values from userspace's point of
* view. For hygiene purposes, the kernel zeroes them on next use,
@@ -233,9 +233,9 @@ static void sve_user_enable(void)
* task->thread.sve_state does not need to be non-NULL, valid or any
* particular size: it must not be dereferenced.
*
- * * FPSR and FPCR are always stored in task->fpsimd_state irrespctive of
- * whether TIF_SVE is clear or set, since these are not vector length
- * dependent.
+ * * FPSR and FPCR are always stored in task->thread.uw.fpsimd_state
+ * irrespective of whether TIF_SVE is clear or set, since these are
+ * not vector length dependent.
*/
/*
@@ -253,10 +253,10 @@ static void task_fpsimd_load(void)
if (system_supports_sve() && test_thread_flag(TIF_SVE))
sve_load_state(sve_pffr(current),
- &current->thread.fpsimd_state.fpsr,
+ &current->thread.uw.fpsimd_state.fpsr,
sve_vq_from_vl(current->thread.sve_vl) - 1);
else
- fpsimd_load_state(&current->thread.fpsimd_state);
+ fpsimd_load_state(&current->thread.uw.fpsimd_state);
if (system_supports_sve()) {
/* Toggle SVE trapping for userspace if needed */
@@ -292,9 +292,9 @@ static void task_fpsimd_save(void)
}
sve_save_state(sve_pffr(current),
- &current->thread.fpsimd_state.fpsr);
+ &current->thread.uw.fpsimd_state.fpsr);
} else
- fpsimd_save_state(&current->thread.fpsimd_state);
+ fpsimd_save_state(&current->thread.uw.fpsimd_state);
}
}
@@ -405,20 +405,21 @@ static int __init sve_sysctl_init(void) { return 0; }
(SVE_SIG_ZREG_OFFSET(vq, n) - SVE_SIG_REGS_OFFSET))
/*
- * Transfer the FPSIMD state in task->thread.fpsimd_state to
+ * Transfer the FPSIMD state in task->thread.uw.fpsimd_state to
* task->thread.sve_state.
*
* Task can be a non-runnable task, or current. In the latter case,
* softirqs (and preemption) must be disabled.
* task->thread.sve_state must point to at least sve_state_size(task)
* bytes of allocated kernel memory.
- * task->thread.fpsimd_state must be up to date before calling this function.
+ * task->thread.uw.fpsimd_state must be up to date before calling this
+ * function.
*/
static void fpsimd_to_sve(struct task_struct *task)
{
unsigned int vq;
void *sst = task->thread.sve_state;
- struct user_fpsimd_state const *fst = &task->thread.fpsimd_state;
+ struct user_fpsimd_state const *fst = &task->thread.uw.fpsimd_state;
unsigned int i;
if (!system_supports_sve())
@@ -432,7 +433,7 @@ static void fpsimd_to_sve(struct task_struct *task)
/*
* Transfer the SVE state in task->thread.sve_state to
- * task->thread.fpsimd_state.
+ * task->thread.uw.fpsimd_state.
*
* Task can be a non-runnable task, or current. In the latter case,
* softirqs (and preemption) must be disabled.
@@ -444,7 +445,7 @@ static void sve_to_fpsimd(struct task_struct *task)
{
unsigned int vq;
void const *sst = task->thread.sve_state;
- struct user_fpsimd_state *fst = &task->thread.fpsimd_state;
+ struct user_fpsimd_state *fst = &task->thread.uw.fpsimd_state;
unsigned int i;
if (!system_supports_sve())
@@ -511,7 +512,7 @@ void fpsimd_sync_to_sve(struct task_struct *task)
}
/*
- * Ensure that task->thread.fpsimd_state is up to date with respect to
+ * Ensure that task->thread.uw.fpsimd_state is up to date with respect to
* the user task, irrespective of whether SVE is in use or not.
*
* This should only be called by ptrace. task must be non-runnable.
@@ -526,21 +527,21 @@ void sve_sync_to_fpsimd(struct task_struct *task)
/*
* Ensure that task->thread.sve_state is up to date with respect to
- * the task->thread.fpsimd_state.
+ * the task->thread.uw.fpsimd_state.
*
* This should only be called by ptrace to merge new FPSIMD register
* values into a task for which SVE is currently active.
* task must be non-runnable.
* task->thread.sve_state must point to at least sve_state_size(task)
* bytes of allocated kernel memory.
- * task->thread.fpsimd_state must already have been initialised with
+ * task->thread.uw.fpsimd_state must already have been initialised with
* the new FPSIMD register values to be merged in.
*/
void sve_sync_from_fpsimd_zeropad(struct task_struct *task)
{
unsigned int vq;
void *sst = task->thread.sve_state;
- struct user_fpsimd_state const *fst = &task->thread.fpsimd_state;
+ struct user_fpsimd_state const *fst = &task->thread.uw.fpsimd_state;
unsigned int i;
if (!test_tsk_thread_flag(task, TIF_SVE))
@@ -910,7 +911,7 @@ void fpsimd_thread_switch(struct task_struct *next)
* upon the next return to userland.
*/
if (__this_cpu_read(fpsimd_last_state.st) ==
- &next->thread.fpsimd_state
+ &next->thread.uw.fpsimd_state
&& next->thread.fpsimd_cpu == smp_processor_id())
clear_tsk_thread_flag(next, TIF_FOREIGN_FPSTATE);
else
@@ -927,8 +928,8 @@ void fpsimd_flush_thread(void)
local_bh_disable();
- memset(&current->thread.fpsimd_state, 0,
- sizeof(current->thread.fpsimd_state));
+ memset(&current->thread.uw.fpsimd_state, 0,
+ sizeof(current->thread.uw.fpsimd_state));
fpsimd_flush_task_state(current);
if (system_supports_sve()) {
@@ -987,7 +988,7 @@ void fpsimd_preserve_current_state(void)
/*
* Like fpsimd_preserve_current_state(), but ensure that
- * current->thread.fpsimd_state is updated so that it can be copied to
+ * current->thread.uw.fpsimd_state is updated so that it can be copied to
* the signal frame.
*/
void fpsimd_signal_preserve_current_state(void)
@@ -1006,7 +1007,7 @@ static void fpsimd_bind_to_cpu(void)
struct fpsimd_last_state_struct *last =
this_cpu_ptr(&fpsimd_last_state);
- last->st = &current->thread.fpsimd_state;
+ last->st = &current->thread.uw.fpsimd_state;
last->sve_in_use = test_thread_flag(TIF_SVE);
current->thread.fpsimd_cpu = smp_processor_id();
}
@@ -1043,7 +1044,7 @@ void fpsimd_update_current_state(struct user_fpsimd_state const *state)
local_bh_disable();
- current->thread.fpsimd_state = *state;
+ current->thread.uw.fpsimd_state = *state;
if (system_supports_sve() && test_thread_flag(TIF_SVE))
fpsimd_to_sve(current);
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index c0da6efe5465..f08a2ed9db0d 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -257,7 +257,7 @@ static void tls_thread_flush(void)
write_sysreg(0, tpidr_el0);
if (is_compat_task()) {
- current->thread.tp_value = 0;
+ current->thread.uw.tp_value = 0;
/*
* We need to ensure ordering between the shadow state and the
@@ -351,7 +351,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
* for the new thread.
*/
if (clone_flags & CLONE_SETTLS)
- p->thread.tp_value = childregs->regs[3];
+ p->thread.uw.tp_value = childregs->regs[3];
} else {
memset(childregs, 0, sizeof(struct pt_regs));
childregs->pstate = PSR_MODE_EL1h;
@@ -379,7 +379,7 @@ static void tls_thread_switch(struct task_struct *next)
tls_preserve_current_state();
if (is_compat_thread(task_thread_info(next)))
- write_sysreg(next->thread.tp_value, tpidrro_el0);
+ write_sysreg(next->thread.uw.tp_value, tpidrro_el0);
else if (!arm64_kernel_unmapped_at_el0())
write_sysreg(0, tpidrro_el0);
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index fd9e8ed22b70..71d99af24ef2 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -629,7 +629,7 @@ static int __fpr_get(struct task_struct *target,
sve_sync_to_fpsimd(target);
- uregs = &target->thread.fpsimd_state;
+ uregs = &target->thread.uw.fpsimd_state;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs,
start_pos, start_pos + sizeof(*uregs));
@@ -655,19 +655,19 @@ static int __fpr_set(struct task_struct *target,
struct user_fpsimd_state newstate;
/*
- * Ensure target->thread.fpsimd_state is up to date, so that a
+ * Ensure target->thread.uw.fpsimd_state is up to date, so that a
* short copyin can't resurrect stale data.
*/
sve_sync_to_fpsimd(target);
- newstate = target->thread.fpsimd_state;
+ newstate = target->thread.uw.fpsimd_state;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate,
start_pos, start_pos + sizeof(newstate));
if (ret)
return ret;
- target->thread.fpsimd_state = newstate;
+ target->thread.uw.fpsimd_state = newstate;
return ret;
}
@@ -692,7 +692,7 @@ static int tls_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
- unsigned long *tls = &target->thread.tp_value;
+ unsigned long *tls = &target->thread.uw.tp_value;
if (target == current)
tls_preserve_current_state();
@@ -705,13 +705,13 @@ static int tls_set(struct task_struct *target, const struct user_regset *regset,
const void *kbuf, const void __user *ubuf)
{
int ret;
- unsigned long tls = target->thread.tp_value;
+ unsigned long tls = target->thread.uw.tp_value;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
if (ret)
return ret;
- target->thread.tp_value = tls;
+ target->thread.uw.tp_value = tls;
return ret;
}
@@ -842,7 +842,7 @@ static int sve_get(struct task_struct *target,
start = end;
end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
- &target->thread.fpsimd_state.fpsr,
+ &target->thread.uw.fpsimd_state.fpsr,
start, end);
if (ret)
return ret;
@@ -941,7 +941,7 @@ static int sve_set(struct task_struct *target,
start = end;
end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
- &target->thread.fpsimd_state.fpsr,
+ &target->thread.uw.fpsimd_state.fpsr,
start, end);
out:
@@ -1169,7 +1169,7 @@ static int compat_vfp_get(struct task_struct *target,
compat_ulong_t fpscr;
int ret, vregs_end_pos;
- uregs = &target->thread.fpsimd_state;
+ uregs = &target->thread.uw.fpsimd_state;
if (target == current)
fpsimd_preserve_current_state();
@@ -1202,7 +1202,7 @@ static int compat_vfp_set(struct task_struct *target,
compat_ulong_t fpscr;
int ret, vregs_end_pos;
- uregs = &target->thread.fpsimd_state;
+ uregs = &target->thread.uw.fpsimd_state;
vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
@@ -1225,7 +1225,7 @@ static int compat_tls_get(struct task_struct *target,
const struct user_regset *regset, unsigned int pos,
unsigned int count, void *kbuf, void __user *ubuf)
{
- compat_ulong_t tls = (compat_ulong_t)target->thread.tp_value;
+ compat_ulong_t tls = (compat_ulong_t)target->thread.uw.tp_value;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
}
@@ -1235,13 +1235,13 @@ static int compat_tls_set(struct task_struct *target,
const void __user *ubuf)
{
int ret;
- compat_ulong_t tls = target->thread.tp_value;
+ compat_ulong_t tls = target->thread.uw.tp_value;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
if (ret)
return ret;
- target->thread.tp_value = tls;
+ target->thread.uw.tp_value = tls;
return ret;
}
@@ -1538,7 +1538,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
break;
case COMPAT_PTRACE_GET_THREAD_AREA:
- ret = put_user((compat_ulong_t)child->thread.tp_value,
+ ret = put_user((compat_ulong_t)child->thread.uw.tp_value,
(compat_ulong_t __user *)datap);
break;
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index bfeee9a51cee..154b7d30145d 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -179,7 +179,8 @@ static void __user *apply_user_offset(
static int preserve_fpsimd_context(struct fpsimd_context __user *ctx)
{
- struct user_fpsimd_state const *fpsimd = &current->thread.fpsimd_state;
+ struct user_fpsimd_state const *fpsimd =
+ &current->thread.uw.fpsimd_state;
int err;
/* copy the FP and status/control registers */
diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c
index 374333703cbd..77b91f478995 100644
--- a/arch/arm64/kernel/signal32.c
+++ b/arch/arm64/kernel/signal32.c
@@ -149,7 +149,8 @@ union __fpsimd_vreg {
static int compat_preserve_vfp_context(struct compat_vfp_sigframe __user *frame)
{
- struct user_fpsimd_state const *fpsimd = &current->thread.fpsimd_state;
+ struct user_fpsimd_state const *fpsimd =
+ &current->thread.uw.fpsimd_state;
compat_ulong_t magic = VFP_MAGIC;
compat_ulong_t size = VFP_STORAGE_SIZE;
compat_ulong_t fpscr, fpexc;
diff --git a/arch/arm64/kernel/sys_compat.c b/arch/arm64/kernel/sys_compat.c
index 9897f416b29e..93ab57dcfc14 100644
--- a/arch/arm64/kernel/sys_compat.c
+++ b/arch/arm64/kernel/sys_compat.c
@@ -90,7 +90,7 @@ long compat_arm_syscall(struct pt_regs *regs)
return do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]);
case __ARM_NR_compat_set_tls:
- current->thread.tp_value = regs->regs[0];
+ current->thread.uw.tp_value = regs->regs[0];
/*
* Protect against register corruption from context switch.
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-14 03:25:49 +0000