Messages in this thread Patch in this message | | | From | "Eric W. Biederman" <> | Date | Wed, 22 May 2019 19:38:55 -0500 | Subject | [REVIEW][PATCH 05/26] signal/bpfilter: Fix bpfilter_kernl to use send_sig not force_sig |
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The locking in force_sig_info is not prepared to deal with a task that exits or execs (as sighand may change). As force_sig is only built to handle synchronous exceptions.
Further the function force_sig_info changes the signal state if the signal is ignored, or blocked or if SIGNAL_UNKILLABLE will prevent the delivery of the signal. The signal SIGKILL can not be ignored and can not be blocked and SIGNAL_UNKILLABLE won't prevent it from being delivered.
So using force_sig rather than send_sig for SIGKILL is pointless.
Because it won't impact the sending of the signal and and because using force_sig is wrong, replace force_sig with send_sig.
Cc: Alexei Starovoitov <ast@kernel.org> Cc: David S. Miller <davem@davemloft.net> Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> --- net/bpfilter/bpfilter_kern.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c index 7ee4fea93637..c0f0990f30b6 100644 --- a/net/bpfilter/bpfilter_kern.c +++ b/net/bpfilter/bpfilter_kern.c @@ -22,7 +22,7 @@ static void shutdown_umh(void) tsk = get_pid_task(find_vpid(bpfilter_ops.info.pid), PIDTYPE_PID); if (tsk) { - force_sig(SIGKILL, tsk); + send_sig(SIGKILL, tsk, 1); put_task_struct(tsk); } } -- 2.21.0
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