sctp_sf_violation_chunk() is not called with asoc argument equal to NULL,
but if that happens it would lead to NULL pointer dereference
in sctp_vtag_verify().

The patch removes code that handles NULL asoc in sctp_sf_violation_chunk().

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Alexey Khoroshilov <redacted>
Proposed-by: Xin Long [off-list ref]
---
 net/sctp/sm_statefuns.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index fb3da4d8f4a3..ec8561dd7e76 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c

@@ -4893,9 +4893,6 @@ static enum sctp_disposition sctp_sf_violation_chunk(
 {
 	static const char err_str[] = "The following chunk violates protocol:";
 
-	if (!asoc)
-		return sctp_sf_violation(net, ep, asoc, type, arg, commands);
-
 	return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str,
 				       sizeof(err_str));
 }

-- 
2.7.4