Syzbot reported corrupted list in em28xx driver. The problem was in non-reinitialized lists on disconnect. Since all 2 lists are global variables and driver can be connected and disconnected many times we should call INIT_LIST_HEAD() in .disconnect method to prevent corrupted list entries. Fixes: 1a23f81b7dc3 ("V4L/DVB (9979): em28xx: move usb probe code to a proper place") Reported-by: syzbot+a6969ef522a36d3344c9@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx> --- drivers/media/usb/em28xx/em28xx-cards.c | 2 ++ drivers/media/usb/em28xx/em28xx-core.c | 6 ++++++ drivers/media/usb/em28xx/em28xx.h | 1 + 3 files changed, 9 insertions(+) diff --git a/drivers/media/usb/em28xx/em28xx-cards.c b/drivers/media/usb/em28xx/em28xx-cards.c index ba9292e2a587..8b1ff79c37a0 100644 --- a/drivers/media/usb/em28xx/em28xx-cards.c +++ b/drivers/media/usb/em28xx/em28xx-cards.c @@ -4148,6 +4148,8 @@ static void em28xx_usb_disconnect(struct usb_interface *intf) dev->dev_next = NULL; } kref_put(&dev->ref, em28xx_free_device); + + em28xx_reset_lists(); } static int em28xx_usb_suspend(struct usb_interface *intf, diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c index 584fa400cd7d..03970ed00dba 100644 --- a/drivers/media/usb/em28xx/em28xx-core.c +++ b/drivers/media/usb/em28xx/em28xx-core.c @@ -1131,6 +1131,12 @@ void em28xx_init_extension(struct em28xx *dev) mutex_unlock(&em28xx_devlist_mutex); } +void em28xx_reset_lists(void) +{ + INIT_LIST_HEAD(&em28xx_devlist); + INIT_LIST_HEAD(&em28xx_extension_devlist); +} + void em28xx_close_extension(struct em28xx *dev) { const struct em28xx_ops *ops = NULL; diff --git a/drivers/media/usb/em28xx/em28xx.h b/drivers/media/usb/em28xx/em28xx.h index ab167cd1f400..73caaaa398d3 100644 --- a/drivers/media/usb/em28xx/em28xx.h +++ b/drivers/media/usb/em28xx/em28xx.h @@ -835,6 +835,7 @@ void em28xx_stop_urbs(struct em28xx *dev); int em28xx_set_mode(struct em28xx *dev, enum em28xx_mode set_mode); int em28xx_gpio_set(struct em28xx *dev, const struct em28xx_reg_seq *gpio); int em28xx_register_extension(struct em28xx_ops *dev); +void em28xx_reset_lists(void); void em28xx_unregister_extension(struct em28xx_ops *dev); void em28xx_init_extension(struct em28xx *dev); void em28xx_close_extension(struct em28xx *dev); -- 2.32.0