This is a note to let you know that I've just added the patch titled
platform/chrome: cros_ec_typec: zero out stale pointers
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
platform-chrome-cros_ec_typec-zero-out-stale-pointer.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3207d8f5bf04eddd4ca238f556869490972dfdbb
Author: Victor Ding <victording@xxxxxxxxxxxx>
Date: Wed Dec 7 09:39:40 2022 +0000
platform/chrome: cros_ec_typec: zero out stale pointers
[ Upstream commit 9a8aadcf0b459c1257b9477fd6402e1d5952ae07 ]
`cros_typec_get_switch_handles` allocates four pointers when obtaining
type-c switch handles. These pointers are all freed if failing to obtain
any of them; therefore, pointers in `port` become stale. The stale
pointers eventually cause use-after-free or double free in later code
paths. Zeroing out all pointer fields after freeing to eliminate these
stale pointers.
Fixes: f28adb41dab4 ("platform/chrome: cros_ec_typec: Register Type C switches")
Fixes: 1a8912caba02 ("platform/chrome: cros_ec_typec: Get retimer handle")
Signed-off-by: Victor Ding <victording@xxxxxxxxxxxx>
Acked-by: Prashant Malani <pmalani@xxxxxxxxxxxx>
Signed-off-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221207093924.v2.1.I1864b6a7ee98824118b93677868d22d3750f439b@changeid
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index d63be2b3d10e..b94abb8f7706 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -157,8 +157,10 @@ static int cros_typec_get_switch_handles(struct cros_typec_port *port,
role_sw_err:
typec_switch_put(port->ori_sw);
+ port->ori_sw = NULL;
ori_sw_err:
typec_mux_put(port->mux);
+ port->mux = NULL;
mux_err:
return -ENODEV;
}
