Description
In the Linux kernel, the following vulnerability has been resolved: rpmsg: core: fix race in driver_override_show() and use core helper The driver_override_show function reads the driver_override string without holding the device_lock. However, the store function modifies and frees the string while holding the device_lock. This creates a race condition where the string can be freed by the store function while being read by the show function, leading to a use-after-free. To fix this, replace the rpmsg_string_attr macro with explicit show and store functions. The new driver_override_store uses the standard driver_set_override helper. Since the introduction of driver_set_override, the comments in include/linux/rpmsg.h have stated that this helper must be used to set or clear driver_override, but the implementation was not updated until now. Because driver_set_override modifies and frees the string while holding the device_lock, the new driver_override_show now correctly holds the device_lock during the read operation to prevent the race. Additionally, since rpmsg_string_attr has only ever been used for driver_override, removing the macro simplifies the code.
Product status
39e47767ec9b22f844c2a07c9d329256960d4021 (git) before 392c6b68334aa0e0ae9aba95c0a366bcb0d92f5d
39e47767ec9b22f844c2a07c9d329256960d4021 (git) before d66b8074c555e8abb0ae19eea1c9f3635498bdde
39e47767ec9b22f844c2a07c9d329256960d4021 (git) before 47615557447185917afa432b7958f87583c417cb
39e47767ec9b22f844c2a07c9d329256960d4021 (git) before 90c8353f471821d7ccd4fe573a2402e056192494
39e47767ec9b22f844c2a07c9d329256960d4021 (git) before 7654e6e3cd6bdee9602f6063b3c670bd556d7e61
39e47767ec9b22f844c2a07c9d329256960d4021 (git) before 2e4a70f3c30910427e5ea848b799066d67b963d5
39e47767ec9b22f844c2a07c9d329256960d4021 (git) before 954557957177c3c13d7c655976665b1170da5e50
39e47767ec9b22f844c2a07c9d329256960d4021 (git) before 42023d4b6d2661a40ee2dcf7e1a3528a35c638ca
4.18
Any version before 4.18
5.10.252 (semver)
5.15.202 (semver)
6.1.165 (semver)
6.6.128 (semver)
6.12.75 (semver)
6.18.16 (semver)
6.19.6 (semver)
7.0 (original_commit_for_fix)
References
git.kernel.org/...c/392c6b68334aa0e0ae9aba95c0a366bcb0d92f5d
git.kernel.org/...c/d66b8074c555e8abb0ae19eea1c9f3635498bdde
git.kernel.org/...c/47615557447185917afa432b7958f87583c417cb
git.kernel.org/...c/90c8353f471821d7ccd4fe573a2402e056192494
git.kernel.org/...c/7654e6e3cd6bdee9602f6063b3c670bd556d7e61
git.kernel.org/...c/2e4a70f3c30910427e5ea848b799066d67b963d5
git.kernel.org/...c/954557957177c3c13d7c655976665b1170da5e50
git.kernel.org/...c/42023d4b6d2661a40ee2dcf7e1a3528a35c638ca