tjh.dev / kernel
Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
1
fork

Configure Feed

Select the types of activity you want to include in your feed.

bus: fsl-mc: fix use-after-free in driver_override_show()

The driver_override_show() function reads the driver_override string
without holding the device_lock. However, driver_override_store() uses
driver_set_override(), which modifies and frees the string while holding
the device_lock.

This can result in a concurrent use-after-free if the string is freed
by the store function while being read by the show function.

Fix this by holding the device_lock around the read operation.

Fixes: 1f86a00c1159 ("bus/fsl-mc: add support for 'driver_override' in the mc-bus")
Cc: stable@vger.kernel.org
Signed-off-by: Gui-Dong Han <hanguidong02@gmail.com>
Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20251202174438.12658-1-hanguidong02@gmail.com
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>

authored by

Gui-Dong Han and committed by
Christophe Leroy (CS GROUP) 148891e9 c8dff80a

+5 -1
+5 -1
drivers/bus/fsl-mc/fsl-mc-bus.c
··· 231 231 struct device_attribute *attr, char *buf) 232 232 { 233 233 struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev); 234 + ssize_t len; 234 235 235 - return sysfs_emit(buf, "%s\n", mc_dev->driver_override); 236 + device_lock(dev); 237 + len = sysfs_emit(buf, "%s\n", mc_dev->driver_override); 238 + device_unlock(dev); 239 + return len; 236 240 } 237 241 static DEVICE_ATTR_RW(driver_override); 238 242