From 9abcabe3111811aeae0f3a14e159b14248631875 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Fri, 30 Apr 2021 17:29:36 -0500 Subject: [PATCH] signal: Implement SIL_FAULT_TRAPNO Now that si_trapno is part of the union in _si_fault and available on all architectures, add SIL_FAULT_TRAPNO and update siginfo_layout to return SIL_FAULT_TRAPNO when the code assumes si_trapno is valid. There is room for future changes to reduce when si_trapno is valid but this is all that is needed to make si_trapno and the other members of the the union in _sigfault mutually exclusive. Update the code that uses siginfo_layout to deal with SIL_FAULT_TRAPNO and have the same code ignore si_trapno in in all other cases. v1: https://lkml.kernel.org/r/m1o8dvs7s7.fsf_-_@fess.ebiederm.org v2: https://lkml.kernel.org/r/20210505141101.11519-6-ebiederm@xmission.com Link: https://lkml.kernel.org/r/20210517195748.8880-2-ebiederm@xmission.com Reviewed-by: Marco Elver Signed-off-by: "Eric W. Biederman" --- fs/signalfd.c | 8 +++----- include/linux/signal.h | 1 + kernel/signal.c | 34 ++++++++++++---------------------- 3 files changed, 16 insertions(+), 27 deletions(-) diff --git a/fs/signalfd.c b/fs/signalfd.c index 040a114..e87e595 100644 --- a/fs/signalfd.c +++ b/fs/signalfd.c @@ -123,15 +123,13 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo, */ case SIL_FAULT: new.ssi_addr = (long) kinfo->si_addr; -#ifdef __ARCH_SI_TRAPNO + break; + case SIL_FAULT_TRAPNO: + new.ssi_addr = (long) kinfo->si_addr; new.ssi_trapno = kinfo->si_trapno; -#endif break; case SIL_FAULT_MCEERR: new.ssi_addr = (long) kinfo->si_addr; -#ifdef __ARCH_SI_TRAPNO - new.ssi_trapno = kinfo->si_trapno; -#endif new.ssi_addr_lsb = (short) kinfo->si_addr_lsb; break; case SIL_PERF_EVENT: diff --git a/include/linux/signal.h b/include/linux/signal.h index 1e98548..5160fd4 100644 --- a/include/linux/signal.h +++ b/include/linux/signal.h @@ -40,6 +40,7 @@ enum siginfo_layout { SIL_TIMER, SIL_POLL, SIL_FAULT, + SIL_FAULT_TRAPNO, SIL_FAULT_MCEERR, SIL_FAULT_BNDERR, SIL_FAULT_PKUERR, diff --git a/kernel/signal.c b/kernel/signal.c index 65888ae..597594e 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1194,6 +1194,7 @@ static inline bool has_si_pid_and_uid(struct kernel_siginfo *info) case SIL_TIMER: case SIL_POLL: case SIL_FAULT: + case SIL_FAULT_TRAPNO: case SIL_FAULT_MCEERR: case SIL_FAULT_BNDERR: case SIL_FAULT_PKUERR: @@ -2527,6 +2528,7 @@ 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_TRAPNO: case SIL_FAULT_MCEERR: case SIL_FAULT_BNDERR: case SIL_FAULT_PKUERR: @@ -3214,6 +3216,10 @@ enum siginfo_layout siginfo_layout(unsigned sig, int si_code) #endif else if ((sig == SIGTRAP) && (si_code == TRAP_PERF)) layout = SIL_PERF_EVENT; +#ifdef __ARCH_SI_TRAPNO + else if (layout == SIL_FAULT) + layout = SIL_FAULT_TRAPNO; +#endif } else if (si_code <= NSIGPOLL) layout = SIL_POLL; @@ -3317,30 +3323,22 @@ void copy_siginfo_to_external32(struct compat_siginfo *to, break; case SIL_FAULT: to->si_addr = ptr_to_compat(from->si_addr); -#ifdef __ARCH_SI_TRAPNO + break; + case SIL_FAULT_TRAPNO: + to->si_addr = ptr_to_compat(from->si_addr); to->si_trapno = from->si_trapno; -#endif break; case SIL_FAULT_MCEERR: to->si_addr = ptr_to_compat(from->si_addr); -#ifdef __ARCH_SI_TRAPNO - to->si_trapno = from->si_trapno; -#endif to->si_addr_lsb = from->si_addr_lsb; break; case SIL_FAULT_BNDERR: to->si_addr = ptr_to_compat(from->si_addr); -#ifdef __ARCH_SI_TRAPNO - to->si_trapno = from->si_trapno; -#endif to->si_lower = ptr_to_compat(from->si_lower); to->si_upper = ptr_to_compat(from->si_upper); break; case SIL_FAULT_PKUERR: to->si_addr = ptr_to_compat(from->si_addr); -#ifdef __ARCH_SI_TRAPNO - to->si_trapno = from->si_trapno; -#endif to->si_pkey = from->si_pkey; break; case SIL_PERF_EVENT: @@ -3401,30 +3399,22 @@ static int post_copy_siginfo_from_user32(kernel_siginfo_t *to, break; case SIL_FAULT: to->si_addr = compat_ptr(from->si_addr); -#ifdef __ARCH_SI_TRAPNO + break; + case SIL_FAULT_TRAPNO: + to->si_addr = compat_ptr(from->si_addr); to->si_trapno = from->si_trapno; -#endif break; case SIL_FAULT_MCEERR: to->si_addr = compat_ptr(from->si_addr); -#ifdef __ARCH_SI_TRAPNO - to->si_trapno = from->si_trapno; -#endif to->si_addr_lsb = from->si_addr_lsb; break; case SIL_FAULT_BNDERR: to->si_addr = compat_ptr(from->si_addr); -#ifdef __ARCH_SI_TRAPNO - to->si_trapno = from->si_trapno; -#endif to->si_lower = compat_ptr(from->si_lower); to->si_upper = compat_ptr(from->si_upper); break; case SIL_FAULT_PKUERR: to->si_addr = compat_ptr(from->si_addr); -#ifdef __ARCH_SI_TRAPNO - to->si_trapno = from->si_trapno; -#endif to->si_pkey = from->si_pkey; break; case SIL_PERF_EVENT: -- 2.7.4