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| author | Eric W. Biederman <ebiederm@xmission.com> | 2017-08-17 23:45:38 +0300 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2018-01-04 03:01:08 +0300 |
| commit | 0b44bf9a6f5cde099ae21b4aa94553484203769a (patch) | |
| tree | 4563f1383ab50d592b8c09ec451121d5fccfdd09 /kernel/signal.c | |
| parent | 30a7acd573899fd8b8ac39236eff6468b195ac7d (diff) | |
| download | linux-0b44bf9a6f5cde099ae21b4aa94553484203769a.tar.xz | |
signal: Simplify and fix kdb_send_sig
- Rename from kdb_send_sig_info to kdb_send_sig
As there is no meaningful siginfo sent
- Use SEND_SIG_PRIV instead of generating a siginfo for a kdb
signal. The generated siginfo had a bogus rationale and was
not correct in the face of pid namespaces. SEND_SIG_PRIV
is simpler and actually correct.
- As the code grabs siglock just send the signal with siglock
held instead of dropping siglock and attempting to grab it again.
- Move the sig_valid test into kdb_kill where it can generate
a good error message.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Diffstat (limited to 'kernel/signal.c')
| -rw-r--r-- | kernel/signal.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index 9558664bd9ec..c894162ec96c 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3684,26 +3684,25 @@ void __init signals_init(void) #ifdef CONFIG_KGDB_KDB #include <linux/kdb.h> /* - * kdb_send_sig_info - Allows kdb to send signals without exposing + * kdb_send_sig - Allows kdb to send signals without exposing * signal internals. This function checks if the required locks are * available before calling the main signal code, to avoid kdb * deadlocks. */ -void -kdb_send_sig_info(struct task_struct *t, struct siginfo *info) +void kdb_send_sig(struct task_struct *t, int sig) { static struct task_struct *kdb_prev_t; - int sig, new_t; + int new_t, ret; if (!spin_trylock(&t->sighand->siglock)) { kdb_printf("Can't do kill command now.\n" "The sigmask lock is held somewhere else in " "kernel, try again later\n"); return; } - spin_unlock(&t->sighand->siglock); new_t = kdb_prev_t != t; kdb_prev_t = t; if (t->state != TASK_RUNNING && new_t) { + spin_unlock(&t->sighand->siglock); kdb_printf("Process is not RUNNING, sending a signal from " "kdb risks deadlock\n" "on the run queue locks. " @@ -3712,8 +3711,9 @@ kdb_send_sig_info(struct task_struct *t, struct siginfo *info) "the deadlock.\n"); return; } - sig = info->si_signo; - if (send_sig_info(sig, info, t)) + ret = send_signal(sig, SEND_SIG_PRIV, t, false); + spin_unlock(&t->sighand->siglock); + if (ret) kdb_printf("Fail to deliver Signal %d to process %d.\n", sig, t->pid); else |