From: Dan Carpenter <dan.carpenter@oracle.com> stable inclusion from stable-5.10.80 commit 508faf8721aea6b67a9e7d77b772f8649080c4f4 bugzilla: 185821 https://gitee.com/openeuler/kernel/issues/I4L7CG Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit c1c8380b0320ab757e60ed90efc8b1992a943256 ] The problem is that "channel" is an unsigned int, when it's less 5 the value of "channel - 5" is not a negative number as one would expect but is very high positive value instead. This means that "start" becomes a very high positive value. The result of that is that we never enter the "for (i = start; i <= end; i++) {" loop. Instead of storing the result from b43legacy_radio_aci_detect() it just uses zero. Fixes: 75388acd0cd8 ("[B43LEGACY]: add mac80211-based driver for legacy BCM43xx devices") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Michael Büsch <m@bues.ch> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Link: https://lore.kernel.org/r/20211006073542.GD8404@kili Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/net/wireless/broadcom/b43legacy/radio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/broadcom/b43legacy/radio.c b/drivers/net/wireless/broadcom/b43legacy/radio.c index 06891b4f837b..fdf78c10a05c 100644 --- a/drivers/net/wireless/broadcom/b43legacy/radio.c +++ b/drivers/net/wireless/broadcom/b43legacy/radio.c @@ -283,7 +283,7 @@ u8 b43legacy_radio_aci_scan(struct b43legacy_wldev *dev) & 0x7FFF); b43legacy_set_all_gains(dev, 3, 8, 1); - start = (channel - 5 > 0) ? channel - 5 : 1; + start = (channel > 5) ? channel - 5 : 1; end = (channel + 5 < 14) ? channel + 5 : 13; for (i = start; i <= end; i++) { -- 2.20.1