From: Yang Xiwen <forbidden405@outlook.com>
Date: Sun, 15 Jun 2025 16:01:10 +0000 (+0800)
Subject: i2c: qup: jump out of the loop in case of timeout
X-Git-Tag: v6.16~3^2^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a7982a14b3012527a9583d12525cd0dc9f8d8934;p=thirdparty%2Fkernel%2Flinux.git

i2c: qup: jump out of the loop in case of timeout

Original logic only sets the return value but doesn't jump out of the
loop if the bus is kept active by a client. This is not expected. A
malicious or buggy i2c client can hang the kernel in this case and
should be avoided. This is observed during a long time test with a
PCA953x GPIO extender.

Fix it by changing the logic to not only sets the return value, but also
jumps out of the loop and return to the caller with -ETIMEDOUT.

Fixes: fbfab1ab0658 ("i2c: qup: reorganization of driver code to remove polling for qup v1")
Signed-off-by: Yang Xiwen <forbidden405@outlook.com>
Cc: <stable@vger.kernel.org> # v4.17+
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250616-qca-i2c-v1-1-2a8d37ee0a30@outlook.com
---

diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
index 6059f585843eb..fc348924d5225 100644
--- a/drivers/i2c/busses/i2c-qup.c
+++ b/drivers/i2c/busses/i2c-qup.c
@@ -452,8 +452,10 @@ static int qup_i2c_bus_active(struct qup_i2c_dev *qup, int len)
 		if (!(status & I2C_STATUS_BUS_ACTIVE))
 			break;
 
-		if (time_after(jiffies, timeout))
+		if (time_after(jiffies, timeout)) {
 			ret = -ETIMEDOUT;
+			break;
+		}
 
 		usleep_range(len, len * 2);
 	}