summaryrefslogtreecommitdiff
path: root/drivers/media/usb
diff options
context:
space:
mode:
authorDuoming Zhou <duoming@zju.edu.cn>2023-05-23 07:59:32 +0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-07-23 13:47:21 +0200
commit784a8027b8ac5a876d71cb3d3d4d97b2b6cb5920 (patch)
tree8d73539cb509f05e989370da6fe3ac05f496b548 /drivers/media/usb
parent1e1af31c4c5dbafb2c332388cb0645e64dfe85cc (diff)
media: usb: siano: Fix warning due to null work_func_t function pointer
[ Upstream commit 6f489a966fbeb0da63d45c2c66a8957eab604bf6 ] The previous commit ebad8e731c1c ("media: usb: siano: Fix use after free bugs caused by do_submit_urb") adds cancel_work_sync() in smsusb_stop_streaming(). But smsusb_stop_streaming() may be called, even if the work_struct surb->wq has not been initialized. As a result, the warning will occur. One of the processes that could lead to warning is shown below: smsusb_probe() smsusb_init_device() if (!dev->in_ep || !dev->out_ep || align < 0) { smsusb_term_device(intf); smsusb_stop_streaming() cancel_work_sync(&dev->surbs[i].wq); __cancel_work_timer() __flush_work() if (WARN_ON(!work->func)) // work->func is null The log reported by syzbot is shown below: WARNING: CPU: 0 PID: 897 at kernel/workqueue.c:3066 __flush_work+0x798/0xa80 kernel/workqueue.c:3063 Modules linked in: CPU: 0 PID: 897 Comm: kworker/0:2 Not tainted 6.2.0-rc1-syzkaller #0 RIP: 0010:__flush_work+0x798/0xa80 kernel/workqueue.c:3066 ... RSP: 0018:ffffc9000464ebf8 EFLAGS: 00010246 RAX: 1ffff11002dbb420 RBX: 0000000000000021 RCX: 1ffffffff204fa4e RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff888016dda0e8 RBP: ffffc9000464ed98 R08: 0000000000000001 R09: ffffffff90253b2f R10: 0000000000000001 R11: 0000000000000000 R12: ffff888016dda0e8 R13: ffff888016dda0e8 R14: ffff888016dda100 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd4331efe8 CR3: 000000000b48e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __cancel_work_timer+0x315/0x460 kernel/workqueue.c:3160 smsusb_stop_streaming drivers/media/usb/siano/smsusb.c:182 [inline] smsusb_term_device+0xda/0x2d0 drivers/media/usb/siano/smsusb.c:344 smsusb_init_device+0x400/0x9ce drivers/media/usb/siano/smsusb.c:419 smsusb_probe+0xbbd/0xc55 drivers/media/usb/siano/smsusb.c:567 ... This patch adds check before cancel_work_sync(). If surb->wq has not been initialized, the cancel_work_sync() will not be executed. Reported-by: syzbot+27b0b464864741b18b99@syzkaller.appspotmail.com Fixes: ebad8e731c1c ("media: usb: siano: Fix use after free bugs caused by do_submit_urb") Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/media/usb')
-rw-r--r--drivers/media/usb/siano/smsusb.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/media/usb/siano/smsusb.c b/drivers/media/usb/siano/smsusb.c
index 1babfe6e2c36..5c223b5498b4 100644
--- a/drivers/media/usb/siano/smsusb.c
+++ b/drivers/media/usb/siano/smsusb.c
@@ -179,7 +179,8 @@ static void smsusb_stop_streaming(struct smsusb_device_t *dev)
for (i = 0; i < MAX_URBS; i++) {
usb_kill_urb(&dev->surbs[i].urb);
- cancel_work_sync(&dev->surbs[i].wq);
+ if (dev->surbs[i].wq.func)
+ cancel_work_sync(&dev->surbs[i].wq);
if (dev->surbs[i].cb) {
smscore_putbuffer(dev->coredev, dev->surbs[i].cb);