diff options
| author | Peter Collingbourne <pcc@google.com> | 2020-11-20 12:33:46 -0800 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-11-23 18:17:39 +0000 |
| commit | dceec3ff78076757311d92a388d50d0251fb7dbb (patch) | |
| tree | e51d2de16335fcd21dce9f5342846d5e868b14ad /arch/arm64/kernel/sys_compat.c | |
| parent | 6ac05e832a9e96f9b1c42a8917cdd317d7b6c8fa (diff) | |
arm64: expose FAR_EL1 tag bits in siginfo
The kernel currently clears the tag bits (i.e. bits 56-63) in the fault
address exposed via siginfo.si_addr and sigcontext.fault_address. However,
the tag bits may be needed by tools in order to accurately diagnose
memory errors, such as HWASan [1] or future tools based on the Memory
Tagging Extension (MTE).
Expose these bits via the arch_untagged_si_addr mechanism, so that
they are only exposed to signal handlers with the SA_EXPOSE_TAGBITS
flag set.
[1] http://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html
Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://linux-review.googlesource.com/id/Ia8876bad8c798e0a32df7c2ce1256c4771c81446
Link: https://lore.kernel.org/r/0010296597784267472fa13b39f8238d87a72cf8.1605904350.git.pcc@google.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel/sys_compat.c')
| -rw-r--r-- | arch/arm64/kernel/sys_compat.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/arch/arm64/kernel/sys_compat.c b/arch/arm64/kernel/sys_compat.c index 3c18c2454089..265fe3eb1069 100644 --- a/arch/arm64/kernel/sys_compat.c +++ b/arch/arm64/kernel/sys_compat.c @@ -68,7 +68,7 @@ do_compat_cache_op(unsigned long start, unsigned long end, int flags) */ long compat_arm_syscall(struct pt_regs *regs, int scno) { - void __user *addr; + unsigned long addr; switch (scno) { /* @@ -111,8 +111,7 @@ long compat_arm_syscall(struct pt_regs *regs, int scno) break; } - addr = (void __user *)instruction_pointer(regs) - - (compat_thumb_mode(regs) ? 2 : 4); + addr = instruction_pointer(regs) - (compat_thumb_mode(regs) ? 2 : 4); arm64_notify_die("Oops - bad compat syscall(2)", regs, SIGILL, ILL_ILLTRP, addr, scno); |