diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/ring_buffer.c | 3 | ||||
| -rw-r--r-- | kernel/hung_task.c | 8 | ||||
| -rw-r--r-- | kernel/signal.c | 61 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_uprobe.c | 9 |
5 files changed, 78 insertions, 7 deletions
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index f4b9a369c8c3..424f5a5fa5a2 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -639,6 +639,9 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags) size = sizeof(struct ring_buffer); size += nr_pages * sizeof(void *); + if (order_base_2(size) >= PAGE_SHIFT+MAX_ORDER) + goto fail; + rb = kzalloc(size, GFP_KERNEL); if (!rb) goto fail; diff --git a/kernel/hung_task.c b/kernel/hung_task.c index e0f90c2b57aa..cc05b97ba569 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -30,7 +30,7 @@ int __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT; * is disabled during the critical section. It also controls the size of * the RCU grace period. So it needs to be upper-bound. */ -#define HUNG_TASK_BATCHING 1024 +#define HUNG_TASK_LOCK_BREAK (HZ / 10) /* * Zero means infinite timeout - no checking done: @@ -158,7 +158,7 @@ static bool rcu_lock_break(struct task_struct *g, struct task_struct *t) static void check_hung_uninterruptible_tasks(unsigned long timeout) { int max_count = sysctl_hung_task_check_count; - int batch_count = HUNG_TASK_BATCHING; + unsigned long last_break = jiffies; struct task_struct *g, *t; /* @@ -172,10 +172,10 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) for_each_process_thread(g, t) { if (!max_count--) goto unlock; - if (!--batch_count) { - batch_count = HUNG_TASK_BATCHING; + if (time_after(jiffies, last_break + HUNG_TASK_LOCK_BREAK)) { if (!rcu_lock_break(g, t)) goto unlock; + last_break = jiffies; } /* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */ if (t->state == TASK_UNINTERRUPTIBLE) diff --git a/kernel/signal.c b/kernel/signal.c index 5b1313309356..96e8c3cbfa38 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -696,6 +696,48 @@ static inline bool si_fromuser(const struct siginfo *info) (!is_si_special(info) && SI_FROMUSER(info)); } +static int dequeue_synchronous_signal(siginfo_t *info) +{ + struct task_struct *tsk = current; + struct sigpending *pending = &tsk->pending; + struct sigqueue *q, *sync = NULL; + + /* + * Might a synchronous signal be in the queue? + */ + if (!((pending->signal.sig[0] & ~tsk->blocked.sig[0]) & SYNCHRONOUS_MASK)) + return 0; + + /* + * Return the first synchronous signal in the queue. + */ + list_for_each_entry(q, &pending->list, list) { + /* Synchronous signals have a postive si_code */ + if ((q->info.si_code > SI_USER) && + (sigmask(q->info.si_signo) & SYNCHRONOUS_MASK)) { + sync = q; + goto next; + } + } + return 0; +next: + /* + * Check if there is another siginfo for the same signal. + */ + list_for_each_entry_continue(q, &pending->list, list) { + if (q->info.si_signo == sync->info.si_signo) + goto still_pending; + } + + sigdelset(&pending->signal, sync->info.si_signo); + recalc_sigpending(); +still_pending: + list_del_init(&sync->list); + copy_siginfo(info, &sync->info); + __sigqueue_free(sync); + return info->si_signo; +} + /* * called with RCU read lock from check_kill_permission() */ @@ -2198,6 +2240,14 @@ relock: goto relock; } + /* Has this task already been marked for death? */ + if (signal_group_exit(signal)) { + ksig->info.si_signo = signr = SIGKILL; + sigdelset(¤t->pending.signal, SIGKILL); + recalc_sigpending(); + goto fatal; + } + for (;;) { struct k_sigaction *ka; @@ -2211,7 +2261,15 @@ relock: goto relock; } - signr = dequeue_signal(current, ¤t->blocked, &ksig->info); + /* + * Signals generated by the execution of an instruction + * need to be delivered before any other pending signals + * so that the instruction pointer in the signal stack + * frame points to the faulting instruction. + */ + signr = dequeue_synchronous_signal(&ksig->info); + if (!signr) + signr = dequeue_signal(current, ¤t->blocked, &ksig->info); if (!signr) break; /* will return 0 */ @@ -2293,6 +2351,7 @@ relock: continue; } + fatal: spin_unlock_irq(&sighand->siglock); /* diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 0651c7f47932..790988e66289 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -39,7 +39,9 @@ static struct { seqcount_t seq; struct timekeeper timekeeper; -} tk_core ____cacheline_aligned; +} tk_core ____cacheline_aligned = { + .seq = SEQCNT_ZERO(tk_core.seq), +}; static DEFINE_RAW_SPINLOCK(timekeeper_lock); static struct timekeeper shadow_timekeeper; diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 31a436f9f13b..0839129fbbd8 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -150,7 +150,14 @@ static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, ret = strncpy_from_user(dst, src, maxlen); if (ret == maxlen) - dst[--ret] = '\0'; + dst[ret - 1] = '\0'; + else if (ret >= 0) + /* + * Include the terminating null byte. In this case it + * was copied by strncpy_from_user but not accounted + * for in ret. + */ + ret++; if (ret < 0) { /* Failed to fetch string */ ((u8 *)get_rloc_data(dest))[0] = '\0'; |