diff options
| author | Puranjay Mohan <puranjay@kernel.org> | 2025-01-15 10:36:47 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-02-08 09:52:08 +0100 |
| commit | eeef8e65041a031bd8a747a392c14b76a123a12c (patch) | |
| tree | 9bc8379a46ba1ae8277eac1a7cf9d5cd7fed32fe | |
| parent | 01220c10a7f48014381b3d9879ce5732744f25fc (diff) | |
bpf: Send signals asynchronously if !preemptible
[ Upstream commit 87c544108b612512b254c8f79aa5c0a8546e2cc4 ]
BPF programs can execute in all kinds of contexts and when a program
running in a non-preemptible context uses the bpf_send_signal() kfunc,
it will cause issues because this kfunc can sleep.
Change `irqs_disabled()` to `!preemptible()`.
Reported-by: syzbot+97da3d7e0112d59971de@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/67486b09.050a0220.253251.0084.GAE@google.com/
Fixes: 1bc7896e9ef4 ("bpf: Fix deadlock with rq_lock in bpf_send_signal()")
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250115103647.38487-1-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | kernel/trace/bpf_trace.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 5f12bb727b85..9d8f60e0cb55 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -853,7 +853,7 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type) if (unlikely(is_global_init(current))) return -EPERM; - if (irqs_disabled()) { + if (!preemptible()) { /* Do an early check on signal validity. Otherwise, * the error is lost in deferred irq_work. */ |