In the Linux kernel, the following vulnerability has been resolved:
proc: protect ptrace_may_access() with exec_update_lock (part 1)
Fix the easy cases where procfs currently calls ptrace_may_access() without exec_update_lock protection, where the fix is to simply add the extra lock or use mm_access():
- do_task_stat(): grab exec_update_lock
- proc_pid_wchan(): grab exec_update_lock
- proc_map_files_lookup(): use mm_access() instead of get_task_mm()
- proc_map_files_readdir(): use mm_access() instead of get_task_mm()
- proc_ns_get_link(): grab exec_update_lock
- proc_ns_readlink(): grab exec_update_lock
References
- https://git.kernel.org/stable/c/4bfe8c481846cee52473a2f7d7b30ee8e6749fc4
- https://git.kernel.org/stable/c/6650527444dadc63d84aa939d14ecba4fadb2f69
- https://git.kernel.org/stable/c/7456ae990a9738962b33146916fabca62ae3d4e0
- https://git.kernel.org/stable/c/ae1e630bcaac739f625822078edbaea98366930d
- https://git.kernel.org/stable/c/bb43679356f1f2a4c6b1c88aec4f021e5b5c74e9
- https://git.kernel.org/stable/c/c1cfd63326f5d09999134e9052c353faf738286e
- https://git.kernel.org/stable/c/d54f14655fd7d7b293698a8b6918563c4c0465e7
- https://git.kernel.org/stable/c/f9b4b03ccc9c69bf7f7298d4559906ebea7143b3