Description

In the Linux kernel, the following vulnerability has been resolved: binfmt_misc: restore write access before closing files opened by open_exec() bm_register_write() opens an executable file using open_exec(), which internally calls do_open_execat() and denies write access on the file to avoid modification while it is being executed. However, when an error occurs, bm_register_write() closes the file using filp_close() directly. This does not restore the write permission, which may cause subsequent write operations on the same file to fail. Fix this by calling exe_file_allow_write_access() before filp_close() to restore the write permission properly.

References 6

• git.kernel.org https://git.kernel.org/stable/c/480ac88431703f2adbb8e6b5bd73c3f3cf9f3d7f
• git.kernel.org https://git.kernel.org/stable/c/54274ff90488b6c0f595a6518faed3cf0bc966eb
• git.kernel.org https://git.kernel.org/stable/c/6cce7bc7fac8471c832696720d9c8f2a976d9c54
• git.kernel.org https://git.kernel.org/stable/c/90f601b497d76f40fa66795c3ecf625b6aced9fd
• git.kernel.org https://git.kernel.org/stable/c/e785f552ab04dbca01d31f0334f4561240b04459
• git.kernel.org https://git.kernel.org/stable/c/fbab8c08e1a6dbaef81e22d672a7647553101d16

Remediation