diff mbox series

[net,15/15] can: j1939: j1939_session_new(): fix skb reference counting

Message ID 20241202090040.1110280-16-mkl@pengutronix.de (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series [net,01/15] can: dev: can_set_termination(): allow sleeping GPIOs | expand

Checks

Context Check Description
netdev/series_format success Pull request is its own cover letter
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 3 this patch: 3
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers fail 5 blamed authors not CCed: bst@pengutronix.de robin@protonic.nl socketcan@hartkopp.net lkp@intel.com dev.kurt@vandijck-laurijssen.be; 5 maintainers not CCed: bst@pengutronix.de robin@protonic.nl socketcan@hartkopp.net lkp@intel.com dev.kurt@vandijck-laurijssen.be
netdev/build_clang success Errors and warnings before: 3 this patch: 3
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 304 this patch: 304
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 8 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest fail net-next-2024-12-02--12-00 (tests: 526)

Commit Message

Marc Kleine-Budde Dec. 2, 2024, 8:55 a.m. UTC 
From: Dmitry Antipov <dmantipov@yandex.ru>

Since j1939_session_skb_queue() does an extra skb_get() for each new
skb, do the same for the initial one in j1939_session_new() to avoid
refcount underflow.

Reported-by: syzbot+d4e8dc385d9258220c31@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d4e8dc385d9258220c31
Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/20241105094823.2403806-1-dmantipov@yandex.ru
[mkl: clean up commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 net/can/j1939/transport.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 319f47df3330..95f7a7e65a73 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -1505,7 +1505,7 @@  static struct j1939_session *j1939_session_new(struct j1939_priv *priv,
 	session->state = J1939_SESSION_NEW;
 
 	skb_queue_head_init(&session->skb_queue);
-	skb_queue_tail(&session->skb_queue, skb);
+	skb_queue_tail(&session->skb_queue, skb_get(skb));
 
 	skcb = j1939_skb_to_cb(skb);
 	memcpy(&session->skcb, skcb, sizeof(session->skcb));