diff options
| author | Dongliang Mu | 2021-07-07 11:34:09 +0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab | 2021-08-04 14:43:49 +0200 |
| commit | 6fa54bc713c262e1cfbc5613377ef52280d7311f (patch) | |
| tree | ebcc8c33d0966590550eebbeee1e6f7a749449e0 /drivers/media | |
| parent | 49be1c78d575eedf862a05aebfd5ab5c24193f61 (diff) | |
media: em28xx-input: fix refcount bug in em28xx_usb_disconnect
If em28xx_ir_init fails, it would decrease the refcount of dev. However,
in the em28xx_ir_fini, when ir is NULL, it goes to ref_put and decrease
the refcount of dev. This will lead to a refcount bug.
Fix this bug by removing the kref_put in the error handling code
of em28xx_ir_init.
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 7 at lib/refcount.c:28 refcount_warn_saturate+0x18e/0x1a0 lib/refcount.c:28
Modules linked in:
CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.13.0 #3
Workqueue: usb_hub_wq hub_event
RIP: 0010:refcount_warn_saturate+0x18e/0x1a0 lib/refcount.c:28
Call Trace:
kref_put.constprop.0+0x60/0x85 include/linux/kref.h:69
em28xx_usb_disconnect.cold+0xd7/0xdc drivers/media/usb/em28xx/em28xx-cards.c:4150
usb_unbind_interface+0xbf/0x3a0 drivers/usb/core/driver.c:458
__device_release_driver drivers/base/dd.c:1201 [inline]
device_release_driver_internal+0x22a/0x230 drivers/base/dd.c:1232
bus_remove_device+0x108/0x160 drivers/base/bus.c:529
device_del+0x1fe/0x510 drivers/base/core.c:3540
usb_disable_device+0xd1/0x1d0 drivers/usb/core/message.c:1419
usb_disconnect+0x109/0x330 drivers/usb/core/hub.c:2221
hub_port_connect drivers/usb/core/hub.c:5151 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5440 [inline]
port_event drivers/usb/core/hub.c:5586 [inline]
hub_event+0xf81/0x1d40 drivers/usb/core/hub.c:5668
process_one_work+0x2c9/0x610 kernel/workqueue.c:2276
process_scheduled_works kernel/workqueue.c:2338 [inline]
worker_thread+0x333/0x5b0 kernel/workqueue.c:2424
kthread+0x188/0x1d0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Reported-by: Dongliang Mu <mudongliangabcd@gmail.com>
Fixes: ac5688637144 ("media: em28xx: Fix possible memory leak of em28xx struct")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/usb/em28xx/em28xx-input.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/drivers/media/usb/em28xx/em28xx-input.c b/drivers/media/usb/em28xx/em28xx-input.c index 59529cbf9cd0..0b6d77c3bec8 100644 --- a/drivers/media/usb/em28xx/em28xx-input.c +++ b/drivers/media/usb/em28xx/em28xx-input.c @@ -842,7 +842,6 @@ error: kfree(ir); ref_put: em28xx_shutdown_buttons(dev); - kref_put(&dev->ref, em28xx_free_device); return err; } |