Re: [PATCH] ath9k: fix possible sleep-in-atomic-context bugs in hif_usb_send_regout()

[Kalle Valo]

Jia-Ju Bai <baijiaju1990@xxxxxxxxx> writes:

> The driver may sleep while holding a spinlock.
> The function call path (from bottom to top) in Linux 4.19 is:
>
> drivers/net/wireless/ath/ath9k/hif_usb.c, 108: 
> 	usb_alloc_urb(GFP_KERNEL) in hif_usb_send_regout
> drivers/net/wireless/ath/ath9k/hif_usb.c, 470: 
> 	hif_usb_send_regout in hif_usb_send
> drivers/net/wireless/ath/ath9k/htc_hst.c, 34: 
> 	(FUNC_PTR)hif_usb_send in htc_issue_send
> drivers/net/wireless/ath/ath9k/htc_hst.c, 295: 
> 	htc_issue_send in htc_send
> drivers/net/wireless/ath/ath9k/htc_drv_beacon.c, 250: 
> 	htc_send in ath9k_htc_send_beacon
> drivers/net/wireless/ath/ath9k/htc_drv_beacon.c, 207: 
> 	spin_lock_bh in ath9k_htc_send_beacon
>
> drivers/net/wireless/ath/ath9k/hif_usb.c, 112: 
> 	kzalloc(GFP_KERNEL) in hif_usb_send_regout
> drivers/net/wireless/ath/ath9k/hif_usb.c, 470: 
> 	hif_usb_send_regout in hif_usb_send
> drivers/net/wireless/ath/ath9k/htc_hst.c, 34: 
> 	(FUNC_PTR)hif_usb_send in htc_issue_send
> drivers/net/wireless/ath/ath9k/htc_hst.c, 295: 
> 	htc_issue_send in htc_send
> drivers/net/wireless/ath/ath9k/htc_drv_beacon.c, 250: 
> 	htc_send in ath9k_htc_send_beacon
> drivers/net/wireless/ath/ath9k/htc_drv_beacon.c, 207: 
> 	spin_lock_bh in ath9k_htc_send_beacon
>
> drivers/net/wireless/ath/ath9k/hif_usb.c, 127: 
> 	usb_submit_urb(GFP_KERNEL) in hif_usb_send_regout
> drivers/net/wireless/ath/ath9k/hif_usb.c, 470: 
> 	hif_usb_send_regout in hif_usb_send
> drivers/net/wireless/ath/ath9k/htc_hst.c, 34: 
> 	(FUNC_PTR)hif_usb_send in htc_issue_send
> drivers/net/wireless/ath/ath9k/htc_hst.c, 295: 
> 	htc_issue_send in htc_send
> drivers/net/wireless/ath/ath9k/htc_drv_beacon.c, 250: 
> 	htc_send in ath9k_htc_send_beacon
> drivers/net/wireless/ath/ath9k/htc_drv_beacon.c, 207: 
> 	spin_lock_bh in ath9k_htc_send_beacon
>
> (FUNC_PTR) means a function pointer is called.
>
> To fix these bugs, GFP_KERNEL is replaced with GFP_ATOMIC.
>
> These bugs are found by a static analysis tool STCheck written by myself.
>
> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>

Can someone else verify this and provide Reviewed-by?

-- 
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