diff mbox series

mwl8k: Fix UAF in mwl8k_fw_state_machine()

Message ID 1634356979-6211-1-git-send-email-zheyuma97@gmail.com (mailing list archive)
State Accepted
Commit 257051a235c17e33782b6e24a4b17f2d7915aaec
Delegated to: Kalle Valo
Headers show
Series mwl8k: Fix UAF in mwl8k_fw_state_machine() | expand

Commit Message

Zheyu Ma Oct. 16, 2021, 4:02 a.m. UTC
When the driver fails to request the firmware, it calls its error
handler. In the error handler, the driver detaches device from driver
first before releasing the firmware, which can cause a UAF bug.

Fix this by releasing firmware first.

The following log reveals it:

[    9.007301 ] BUG: KASAN: use-after-free in mwl8k_fw_state_machine+0x320/0xba0
[    9.010143 ] Workqueue: events request_firmware_work_func
[    9.010830 ] Call Trace:
[    9.010830 ]  dump_stack_lvl+0xa8/0xd1
[    9.010830 ]  print_address_description+0x87/0x3b0
[    9.010830 ]  kasan_report+0x172/0x1c0
[    9.010830 ]  ? mutex_unlock+0xd/0x10
[    9.010830 ]  ? mwl8k_fw_state_machine+0x320/0xba0
[    9.010830 ]  ? mwl8k_fw_state_machine+0x320/0xba0
[    9.010830 ]  __asan_report_load8_noabort+0x14/0x20
[    9.010830 ]  mwl8k_fw_state_machine+0x320/0xba0
[    9.010830 ]  ? mwl8k_load_firmware+0x5f0/0x5f0
[    9.010830 ]  request_firmware_work_func+0x172/0x250
[    9.010830 ]  ? read_lock_is_recursive+0x20/0x20
[    9.010830 ]  ? process_one_work+0x7a1/0x1100
[    9.010830 ]  ? request_firmware_nowait+0x460/0x460
[    9.010830 ]  ? __this_cpu_preempt_check+0x13/0x20
[    9.010830 ]  process_one_work+0x9bb/0x1100

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
---
 drivers/net/wireless/marvell/mwl8k.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Kalle Valo Oct. 20, 2021, 8:41 a.m. UTC | #1
Zheyu Ma <zheyuma97@gmail.com> wrote:

> When the driver fails to request the firmware, it calls its error
> handler. In the error handler, the driver detaches device from driver
> first before releasing the firmware, which can cause a use-after-free bug.
> 
> Fix this by releasing firmware first.
> 
> The following log reveals it:
> 
> [    9.007301 ] BUG: KASAN: use-after-free in mwl8k_fw_state_machine+0x320/0xba0
> [    9.010143 ] Workqueue: events request_firmware_work_func
> [    9.010830 ] Call Trace:
> [    9.010830 ]  dump_stack_lvl+0xa8/0xd1
> [    9.010830 ]  print_address_description+0x87/0x3b0
> [    9.010830 ]  kasan_report+0x172/0x1c0
> [    9.010830 ]  ? mutex_unlock+0xd/0x10
> [    9.010830 ]  ? mwl8k_fw_state_machine+0x320/0xba0
> [    9.010830 ]  ? mwl8k_fw_state_machine+0x320/0xba0
> [    9.010830 ]  __asan_report_load8_noabort+0x14/0x20
> [    9.010830 ]  mwl8k_fw_state_machine+0x320/0xba0
> [    9.010830 ]  ? mwl8k_load_firmware+0x5f0/0x5f0
> [    9.010830 ]  request_firmware_work_func+0x172/0x250
> [    9.010830 ]  ? read_lock_is_recursive+0x20/0x20
> [    9.010830 ]  ? process_one_work+0x7a1/0x1100
> [    9.010830 ]  ? request_firmware_nowait+0x460/0x460
> [    9.010830 ]  ? __this_cpu_preempt_check+0x13/0x20
> [    9.010830 ]  process_one_work+0x9bb/0x1100
> 
> Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>

Patch applied to wireless-drivers-next.git, thanks.

257051a235c1 mwl8k: Fix use-after-free in mwl8k_fw_state_machine()
diff mbox series

Patch

diff --git a/drivers/net/wireless/marvell/mwl8k.c b/drivers/net/wireless/marvell/mwl8k.c
index 3bf6571f4149..529e325498cd 100644
--- a/drivers/net/wireless/marvell/mwl8k.c
+++ b/drivers/net/wireless/marvell/mwl8k.c
@@ -5800,8 +5800,8 @@  static void mwl8k_fw_state_machine(const struct firmware *fw, void *context)
 fail:
 	priv->fw_state = FW_STATE_ERROR;
 	complete(&priv->firmware_loading_complete);
-	device_release_driver(&priv->pdev->dev);
 	mwl8k_release_firmware(priv);
+	device_release_driver(&priv->pdev->dev);
 }
 
 #define MAX_RESTART_ATTEMPTS 1