diff options
Diffstat (limited to 'kernel/signal.c')
-rw-r--r-- | kernel/signal.c | 103 |
1 files changed, 36 insertions, 67 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index 66e88649cf74..30a0bee5ff9b 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -431,16 +431,7 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t gfp_flags, rcu_read_unlock(); if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) { - /* - * Preallocation does not hold sighand::siglock so it can't - * use the cache. The lockless caching requires that only - * one consumer and only one producer run at a time. - */ - q = READ_ONCE(t->sigqueue_cache); - if (!q || sigqueue_flags) - q = kmem_cache_alloc(sigqueue_cachep, gfp_flags); - else - WRITE_ONCE(t->sigqueue_cache, NULL); + q = kmem_cache_alloc(sigqueue_cachep, gfp_flags); } else { print_dropped_signal(sig); } @@ -457,44 +448,13 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t gfp_flags, return q; } -void exit_task_sigqueue_cache(struct task_struct *tsk) -{ - /* Race free because @tsk is mopped up */ - struct sigqueue *q = tsk->sigqueue_cache; - - if (q) { - tsk->sigqueue_cache = NULL; - /* - * Hand it back to the cache as the task might - * be self reaping which would leak the object. - */ - kmem_cache_free(sigqueue_cachep, q); - } -} - -static void sigqueue_cache_or_free(struct sigqueue *q) -{ - /* - * Cache one sigqueue per task. This pairs with the consumer side - * in __sigqueue_alloc() and needs READ/WRITE_ONCE() to prevent the - * compiler from store tearing and to tell KCSAN that the data race - * is intentional when run without holding current->sighand->siglock, - * which is fine as current obviously cannot run __sigqueue_free() - * concurrently. - */ - if (!READ_ONCE(current->sigqueue_cache)) - WRITE_ONCE(current->sigqueue_cache, q); - else - kmem_cache_free(sigqueue_cachep, q); -} - static void __sigqueue_free(struct sigqueue *q) { if (q->flags & SIGQUEUE_PREALLOC) return; if (atomic_dec_and_test(&q->user->sigpending)) free_uid(q->user); - sigqueue_cache_or_free(q); + kmem_cache_free(sigqueue_cachep, q); } void flush_sigqueue(struct sigpending *queue) @@ -1236,6 +1196,7 @@ 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: @@ -1804,6 +1765,21 @@ int force_sig_pkuerr(void __user *addr, u32 pkey) } #endif +int force_sig_perf(void __user *addr, u32 type, u64 sig_data) +{ + struct kernel_siginfo info; + + clear_siginfo(&info); + info.si_signo = SIGTRAP; + info.si_errno = 0; + info.si_code = TRAP_PERF; + info.si_addr = addr; + info.si_perf_data = sig_data; + info.si_perf_type = type; + + return force_sig_info(&info); +} + /* For the crazy architectures that include trap information in * the errno field, instead of an actual errno value. */ @@ -2564,6 +2540,7 @@ 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: @@ -3251,6 +3228,10 @@ 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; @@ -3354,35 +3335,28 @@ 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: to->si_addr = ptr_to_compat(from->si_addr); - to->si_perf = from->si_perf; + to->si_perf_data = from->si_perf_data; + to->si_perf_type = from->si_perf_type; break; case SIL_CHLD: to->si_pid = from->si_pid; @@ -3438,35 +3412,28 @@ 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: to->si_addr = compat_ptr(from->si_addr); - to->si_perf = from->si_perf; + to->si_perf_data = from->si_perf_data; + to->si_perf_type = from->si_perf_type; break; case SIL_CHLD: to->si_pid = from->si_pid; @@ -4644,11 +4611,13 @@ static inline void siginfo_buildtime_checks(void) /* sigfault */ CHECK_OFFSET(si_addr); + CHECK_OFFSET(si_trapno); CHECK_OFFSET(si_addr_lsb); CHECK_OFFSET(si_lower); CHECK_OFFSET(si_upper); CHECK_OFFSET(si_pkey); - CHECK_OFFSET(si_perf); + CHECK_OFFSET(si_perf_data); + CHECK_OFFSET(si_perf_type); /* sigpoll */ CHECK_OFFSET(si_band); |