This is a note to let you know that I've just added the patch titled
rpmsg: char: Avoid double destroy of default endpoint
to the 5.19-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:
rpmsg-char-avoid-double-destroy-of-default-endpoint.patch
and it can be found in the queue-5.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 467233a4ac29b215d492843d067a9f091e6bf0c5 Mon Sep 17 00:00:00 2001
From: Shengjiu Wang <shengjiu.wang@xxxxxxx>
Date: Wed, 21 Sep 2022 09:58:43 +0800
Subject: rpmsg: char: Avoid double destroy of default endpoint
From: Shengjiu Wang <shengjiu.wang@xxxxxxx>
commit 467233a4ac29b215d492843d067a9f091e6bf0c5 upstream.
The rpmsg_dev_remove() in rpmsg_core is the place for releasing
this default endpoint.
So need to avoid destroying the default endpoint in
rpmsg_chrdev_eptdev_destroy(), this should be the same as
rpmsg_eptdev_release(). Otherwise there will be double destroy
issue that ept->refcount report warning:
refcount_t: underflow; use-after-free.
Call trace:
refcount_warn_saturate+0xf8/0x150
virtio_rpmsg_destroy_ept+0xd4/0xec
rpmsg_dev_remove+0x60/0x70
The issue can be reproduced by stopping remoteproc before
closing the /dev/rpmsgX.
Fixes: bea9b79c2d10 ("rpmsg: char: Add possibility to use default endpoint of the rpmsg device")
Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
Reviewed-by: Peng Fan <peng.fan@xxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1663725523-6514-1-git-send-email-shengjiu.wang@xxxxxxx
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/rpmsg/rpmsg_char.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/rpmsg/rpmsg_char.c
+++ b/drivers/rpmsg/rpmsg_char.c
@@ -76,7 +76,9 @@ int rpmsg_chrdev_eptdev_destroy(struct d
mutex_lock(&eptdev->ept_lock);
if (eptdev->ept) {
- rpmsg_destroy_ept(eptdev->ept);
+ /* The default endpoint is released by the rpmsg core */
+ if (!eptdev->default_ept)
+ rpmsg_destroy_ept(eptdev->ept);
eptdev->ept = NULL;
}
mutex_unlock(&eptdev->ept_lock);
Patches currently in stable-queue which might be from shengjiu.wang@xxxxxxx are
queue-5.19/rpmsg-char-avoid-double-destroy-of-default-endpoint.patch
