diff options
author | Anton Vorontsov <anton.vorontsov@linaro.org> | 2012-02-07 07:49:39 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-09 18:03:29 +0100 |
commit | e502babe0a85226f2417b60a8710cf8192879180 (patch) | |
tree | 6964ef225b6eded57757425c6faf3c59d1d0c21e /drivers/tty/sysrq.c | |
parent | serial: pch_uart: trivail cleanup by removing the pch_uart_hal_request() (diff) | |
download | linux-e502babe0a85226f2417b60a8710cf8192879180.tar.xz linux-e502babe0a85226f2417b60a8710cf8192879180.zip |
sysrq: Fix possible race with exiting task
sysrq should grab the tasklist lock, otherwise calling force_sig() is
not safe, as it might race with exiting task, which ->sighand might be
set to NULL already.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/sysrq.c')
-rw-r--r-- | drivers/tty/sysrq.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c index 7867b7c4538e..a1bcad7ef739 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -322,11 +322,13 @@ static void send_sig_all(int sig) { struct task_struct *p; + read_lock(&tasklist_lock); for_each_process(p) { if (p->mm && !is_global_init(p)) /* Not swapper, init nor kernel thread */ force_sig(sig, p); } + read_unlock(&tasklist_lock); } static void sysrq_handle_term(int key) |