From: Karl Mehltretter Date: Sun, 19 Jul 2026 12:11:40 +0000 (+0200) Subject: pinctrl: devicetree: don't free uninitialized dev_name on error path X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=015b5bcbcb622b32317642be91a7f79aa5413649;p=thirdparty%2Fkernel%2Flinux.git pinctrl: devicetree: don't free uninitialized dev_name on error path dt_remember_or_free_map() duplicates dev_name for each map entry. If kstrdup_const() fails, dt_free_map() frees dev_name in all num_maps entries, including entries that have not been initialized. Some pinctrl drivers, including pinctrl-imx, allocate the map with kmalloc() and leave dev_name for the core to initialize. The untouched entries therefore contain uninitialized data which is passed to kfree_const(). Reproduced on qemu's mcimx6ul-evk (pinctrl-imx) with failslab injection while binding the pinctrl-consuming device, under KASAN: BUG: KASAN: double-free in dt_free_map+0x34/0xa4 Free of addr c425a900 by task init/1 kfree from dt_free_map+0x34/0xa4 dt_free_map from dt_remember_or_free_map+0x184/0x198 dt_remember_or_free_map from pinctrl_dt_to_map+0x33c/0x4c8 pinctrl_dt_to_map from create_pinctrl+0x9c/0x5c0 Initialize all dev_name fields to NULL before duplicating the device name, making the full-map cleanup safe after a partial failure. Fixes: be4c60b563ed ("pinctrl: devicetree: Avoid taking direct reference to device name string") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-fable-5 Signed-off-by: Karl Mehltretter Signed-off-by: Linus Walleij --- diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c index 02a271dd292f..465b43092eb7 100644 --- a/drivers/pinctrl/devicetree.c +++ b/drivers/pinctrl/devicetree.c @@ -69,6 +69,10 @@ static int dt_remember_or_free_map(struct pinctrl *p, const char *statename, int i; struct pinctrl_dt_map *dt_map; + /* Initialize dev_name before any allocation can fail */ + for (i = 0; i < num_maps; i++) + map[i].dev_name = NULL; + /* Initialize common mapping table entry fields */ for (i = 0; i < num_maps; i++) { const char *devname;