This patch try to fix bug reported by syzkaller:
divide error: 0000 [#1] SMP KASAN
CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 5.15.0-rc5-syzkaller #0
Hardware name: Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events request_firmware_work_func
RIP: 0010:mwifiex_write_data_sync drivers/net/wireless/marvell/mwifiex/usb.c:696 [inline]
RIP: 0010:mwifiex_prog_fw_w_helper drivers/net/wireless/marvell/mwifiex/usb.c:1437 [inline]
RIP: 0010:mwifiex_usb_dnld_fw+0xabd/0x11a0 drivers/net/wireless/marvell/mwifiex/usb.c:1518
Call Trace:
_mwifiex_fw_dpc+0x181/0x10a0 drivers/net/wireless/marvell/mwifiex/main.c:542
request_firmware_work_func+0x12c/0x230 drivers/base/firmware_loader/main.c:1081
process_one_work+0x9bf/0x1620 kernel/workqueue.c:2297
worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
kthread+0x3c2/0x4a0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Link: https://syzkaller.appspot.com/bug?extid=4e7b6c94d22f4bfca9a0
Reported-and-tested-by: [email protected]
Signed-off-by: Wan Jiabing <[email protected]>
---
drivers/net/wireless/marvell/mwifiex/usb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/marvell/mwifiex/usb.c b/drivers/net/wireless/marvell/mwifiex/usb.c
index 426e39d4ccf0..c24ec27d4057 100644
--- a/drivers/net/wireless/marvell/mwifiex/usb.c
+++ b/drivers/net/wireless/marvell/mwifiex/usb.c
@@ -693,7 +693,7 @@ static int mwifiex_write_data_sync(struct mwifiex_adapter *adapter, u8 *pbuf,
struct usb_card_rec *card = adapter->card;
int actual_length, ret;
- if (!(*len % card->bulk_out_maxpktsize))
+ if (card->bulk_out_maxpktsize && !(*len % card->bulk_out_maxpktsize))
(*len)++;
/* Send the data block */
--
2.20.1
On 10/18/21 8:31 PM, Wan Jiabing wrote:
> This patch try to fix bug reported by syzkaller:
> divide error: 0000 [#1] SMP KASAN
> CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 5.15.0-rc5-syzkaller #0
> Hardware name: Google Compute Engine, BIOS Google 01/01/2011
> Workqueue: events request_firmware_work_func
> RIP: 0010:mwifiex_write_data_sync drivers/net/wireless/marvell/mwifiex/usb.c:696 [inline]
> RIP: 0010:mwifiex_prog_fw_w_helper drivers/net/wireless/marvell/mwifiex/usb.c:1437 [inline]
> RIP: 0010:mwifiex_usb_dnld_fw+0xabd/0x11a0 drivers/net/wireless/marvell/mwifiex/usb.c:1518
> Call Trace:
> _mwifiex_fw_dpc+0x181/0x10a0 drivers/net/wireless/marvell/mwifiex/main.c:542
> request_firmware_work_func+0x12c/0x230 drivers/base/firmware_loader/main.c:1081
> process_one_work+0x9bf/0x1620 kernel/workqueue.c:2297
> worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
> kthread+0x3c2/0x4a0 kernel/kthread.c:319
> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
>
> Link: https://syzkaller.appspot.com/bug?extid=4e7b6c94d22f4bfca9a0
Please provide a Fixes: tag
> Reported-and-tested-by: [email protected]
> Signed-off-by: Wan Jiabing <[email protected]>
> ---
> drivers/net/wireless/marvell/mwifiex/usb.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/marvell/mwifiex/usb.c b/drivers/net/wireless/marvell/mwifiex/usb.c
> index 426e39d4ccf0..c24ec27d4057 100644
> --- a/drivers/net/wireless/marvell/mwifiex/usb.c
> +++ b/drivers/net/wireless/marvell/mwifiex/usb.c
> @@ -693,7 +693,7 @@ static int mwifiex_write_data_sync(struct mwifiex_adapter *adapter, u8 *pbuf,
> struct usb_card_rec *card = adapter->card;
> int actual_length, ret;
>
> - if (!(*len % card->bulk_out_maxpktsize))
> + if (card->bulk_out_maxpktsize && !(*len % card->bulk_out_maxpktsize))
Are you sure this fix is not working around the real bug ?
In which cases bulk_out_maxpktsize would be zero ?
If this is a valid case, this needs to be explained in the changelog.
> (*len)++;
>
> /* Send the data block */
>