diff options
Diffstat (limited to 'kernel/signal.c')
| -rw-r--r-- | kernel/signal.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index ef8f2a28d37c..26018c59821d 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2524,6 +2524,26 @@ static int ptrace_signal(int signr, kernel_siginfo_t *info) return signr; } +static void hide_si_addr_tag_bits(struct ksignal *ksig) +{ + switch (siginfo_layout(ksig->sig, ksig->info.si_code)) { + case SIL_FAULT: + case SIL_FAULT_MCEERR: + case SIL_FAULT_BNDERR: + case SIL_FAULT_PKUERR: + ksig->info.si_addr = arch_untagged_si_addr( + ksig->info.si_addr, ksig->sig, ksig->info.si_code); + break; + case SIL_KILL: + case SIL_TIMER: + case SIL_POLL: + case SIL_CHLD: + case SIL_RT: + case SIL_SYS: + break; + } +} + bool get_signal(struct ksignal *ksig) { struct sighand_struct *sighand = current->sighand; @@ -2761,6 +2781,10 @@ relock: spin_unlock_irq(&sighand->siglock); ksig->sig = signr; + + if (!(ksig->ka.sa.sa_flags & SA_EXPOSE_TAGBITS)) + hide_si_addr_tag_bits(ksig); + return ksig->sig > 0; } @@ -3985,6 +4009,22 @@ int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) if (oact) *oact = *k; + /* + * Make sure that we never accidentally claim to support SA_UNSUPPORTED, + * e.g. by having an architecture use the bit in their uapi. + */ + BUILD_BUG_ON(UAPI_SA_FLAGS & SA_UNSUPPORTED); + + /* + * Clear unknown flag bits in order to allow userspace to detect missing + * support for flag bits and to allow the kernel to use non-uapi bits + * internally. + */ + if (act) + act->sa.sa_flags &= UAPI_SA_FLAGS; + if (oact) + oact->sa.sa_flags &= UAPI_SA_FLAGS; + sigaction_compat_abi(act, oact); if (act) { |