diff options
| author | Votokina Victoria <Victoria.Votokina@kaspersky.com> | 2026-02-03 14:31:57 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-02-26 15:01:11 -0800 |
| commit | 1cb97b1225450af3f7b728777929ba50c6a58ced (patch) | |
| tree | c4c34390ee89f6398803547a18acd869daddf340 | |
| parent | 719d3932b8f6e3348ce2f0ac58e278301fc17575 (diff) | |
nfc: hci: shdlc: Stop timers and work before freeing context
[ Upstream commit c9efde1e537baed7648a94022b43836a348a074f ]
llc_shdlc_deinit() purges SHDLC skb queues and frees the llc_shdlc
structure while its timers and state machine work may still be active.
Timer callbacks can schedule sm_work, and sm_work accesses SHDLC state
and the skb queues. If teardown happens in parallel with a queued/running
work item, it can lead to UAF and other shutdown races.
Stop all SHDLC timers and cancel sm_work synchronously before purging the
queues and freeing the context.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 4a61cd6687fc ("NFC: Add an shdlc llc module to llc core")
Signed-off-by: Votokina Victoria <Victoria.Votokina@kaspersky.com>
Link: https://patch.msgid.link/20260203113158.2008723-1-Victoria.Votokina@kaspersky.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/nfc/hci/llc_shdlc.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/net/nfc/hci/llc_shdlc.c b/net/nfc/hci/llc_shdlc.c index 4fc37894860c..08c8aa1530d8 100644 --- a/net/nfc/hci/llc_shdlc.c +++ b/net/nfc/hci/llc_shdlc.c @@ -762,6 +762,14 @@ static void llc_shdlc_deinit(struct nfc_llc *llc) { struct llc_shdlc *shdlc = nfc_llc_get_data(llc); + timer_shutdown_sync(&shdlc->connect_timer); + timer_shutdown_sync(&shdlc->t1_timer); + timer_shutdown_sync(&shdlc->t2_timer); + shdlc->t1_active = false; + shdlc->t2_active = false; + + cancel_work_sync(&shdlc->sm_work); + skb_queue_purge(&shdlc->rcv_q); skb_queue_purge(&shdlc->send_q); skb_queue_purge(&shdlc->ack_pending_q); |