From: Amir Mohammad Jahangirzad Date: Sat, 18 Apr 2026 00:42:47 +0000 (+0330) Subject: wifi: libertas: fix integer underflow in process_cmdrequest() X-Git-Tag: v7.1-rc3~26^2~22^2~14 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3994b4afd521d60e47e012fe2ed7b606aaec370b;p=thirdparty%2Fkernel%2Flinux.git wifi: libertas: fix integer underflow in process_cmdrequest() The existing validation only checks if recvlength exceeds LBS_CMD_BUFFER_SIZE, but doesn't check the lower bound. When a USB device sends a response shorter than MESSAGE_HEADER_LEN, the subtraction (recvlength - MESSAGE_HEADER_LEN) wraps to a huge value, causing memcpy to corrupt the heap. Add the same lower bound check that libertas_tf already has. Signed-off-by: Amir Mohammad Jahangirzad Link: https://patch.msgid.link/20260418004247.368944-1-a.jahangirzad@gmail.com Signed-off-by: Johannes Berg --- diff --git a/drivers/net/wireless/marvell/libertas/if_usb.c b/drivers/net/wireless/marvell/libertas/if_usb.c index 4fae0e335136..a00d53350fa9 100644 --- a/drivers/net/wireless/marvell/libertas/if_usb.c +++ b/drivers/net/wireless/marvell/libertas/if_usb.c @@ -633,9 +633,10 @@ static inline void process_cmdrequest(int recvlength, uint8_t *recvbuff, unsigned long flags; u8 i; - if (recvlength > LBS_CMD_BUFFER_SIZE) { + if (recvlength < MESSAGE_HEADER_LEN || + recvlength > LBS_CMD_BUFFER_SIZE) { lbs_deb_usbd(&cardp->udev->dev, - "The receive buffer is too large\n"); + "The receive buffer is invalid: %d\n", recvlength); kfree_skb(skb); return; }