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| author | Eric W. Biederman <ebiederm@xmission.com> | 2018-01-04 02:04:34 +0100 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2018-01-12 21:23:53 +0100 |
| commit | 90bc9fb15942ad08b46cd003d8d1b51f3d43e322 (patch) | |
| tree | afdec849db739ddb9cfc401a3acb1290bb845a37 | |
| parent | mn10300/misalignment: Use SIGSEGV SEGV_MAPERR to report a failed user copy (diff) | |
| download | linux-90bc9fb15942ad08b46cd003d8d1b51f3d43e322.tar.xz linux-90bc9fb15942ad08b46cd003d8d1b51f3d43e322.zip | |
x86/mm/pkeys: Fix fill_sig_info_pkey
SEGV_PKUERR is a signal specific si_code which happens to have the
same numeric value as several others: BUS_MCEERR_AR, ILL_ILLTRP,
FPE_FLTOVF, TRAP_HWBKPT, CLD_TRAPPED, POLL_ERR, SEGV_THREAD_ID,
as such it is not safe to just test the si_code the signal number
must also be tested to prevent a false positive in fill_sig_info_pkey.
I found this error by inspection, and BUS_MCEERR_AR appears to
be a real candidate for confusion. So pass in si_signo and fix it.
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Fixes: 019132ff3daf ("x86/mm/pkeys: Fill in pkey field in siginfo")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| -rw-r--r-- | arch/x86/mm/fault.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 06fe3d51d385..b3e40773dce0 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -172,14 +172,15 @@ is_prefetch(struct pt_regs *regs, unsigned long error_code, unsigned long addr) * 6. T1 : reaches here, sees vma_pkey(vma)=5, when we really * faulted on a pte with its pkey=4. */ -static void fill_sig_info_pkey(int si_code, siginfo_t *info, u32 *pkey) +static void fill_sig_info_pkey(int si_signo, int si_code, siginfo_t *info, + u32 *pkey) { /* This is effectively an #ifdef */ if (!boot_cpu_has(X86_FEATURE_OSPKE)) return; /* Fault not from Protection Keys: nothing to do */ - if (si_code != SEGV_PKUERR) + if ((si_code != SEGV_PKUERR) || (si_signo != SIGSEGV)) return; /* * force_sig_info_fault() is called from a number of @@ -218,7 +219,7 @@ force_sig_info_fault(int si_signo, int si_code, unsigned long address, lsb = PAGE_SHIFT; info.si_addr_lsb = lsb; - fill_sig_info_pkey(si_code, &info, pkey); + fill_sig_info_pkey(si_signo, si_code, &info, pkey); force_sig_info(si_signo, &info, tsk); } |