CVE-2026-63797

Description

In the Linux kernel, the following vulnerability has been resolved: rpmsg: char: Fix use-after-free on probe error path rpmsg_chrdev_probe() stores the newly allocated eptdev in the default endpoint's priv pointer before calling rpmsg_chrdev_eptdev_add(). If rpmsg_chrdev_eptdev_add() then fails, its error path frees eptdev while the default endpoint may still dispatch callbacks with the stale priv pointer. Avoid publishing eptdev through the default endpoint until rpmsg_chrdev_eptdev_add() succeeds. Messages received before the priv pointer is published should be ignored by rpmsg_ept_cb(). Flow-control updates can hit rpmsg_ept_flow_cb() in the same window, so make both callbacks return success when priv is NULL.

References

• https://git.kernel.org/stable/c/104d100212396801f1d9d388282f746e23e2bfd6
• https://git.kernel.org/stable/c/1ff3f528e67d20e2b1483dcaba899dc7832b2e6b
• https://git.kernel.org/stable/c/c5ebb06c7e24d531b68707168e04698859d642bc
• https://git.kernel.org/stable/c/ddf13f91ca82c94ef7ad9c41a434a03313f8eb1b
• https://git.kernel.org/stable/c/ff268cd9ccbce6472a0658791b417bf11c31ee39