Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: binfmt_misc: use exe_file_deny_write_access() for the interpreter clone For MISC_FMT_OPEN_FILE entries load_misc_binary() clones the registered interpreter file and denies write access to the clone via plain deny_write_access(). The clone is installed as bprm->interpreter and later released by the exec machinery through exe_file_allow_write_access() which skips the i_writecount increment for files with FMODE_FSNOTIFY_HSM set. The deny and allow side can therefore come to different conclusions when pre-content watches are in play: if a pre-content watch is added to the interpreter after registration every subsequent exec through that entry takes a write denial on the clone that is never paired with a write allowance, driving the interpreter inode's i_writecount further down with each exec and leaving the interpreter unwritable even after the entry and all its users are gone. Take the write denial via exe_file_deny_write_access() so both sides of the pairing base their decision on the same file mode, and propagate failure instead of silently ignoring it: an interpreter that is concurrently open for writing now fails the exec with ETXTBSY, exactly like an interpreter freshly opened via open_exec() would.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 5b432413f7bbbc8b935138490a57be05c1921684 before c65eb018c12179b5e2c7afe1f0956298576fecec; affected bb4715098d8e340bbbdd3a874b31f89867c8067e before 2bd860b7e752a51185960143cab9fec7bf32c84e; affected c152be5adc0975c75cc4f50891c9072d52d60b47 before eea4b7c7711b1e425272d23352af157f45f4c3e3; affected bf5ed2ef5cdb7b47ce606e3d48ea6eb803b31503 before 2fdf8b07bee5ef99ec77773a6be05fbb8ee5cdb9; affected 483217fd6f7ccd98b3ed2531a54f75ed144b4499 before f1e7ea3c8e070f19771cdaef55bbeda1359ad490; affected 0357ef03c94ef835bd44a0658b8edb672a9dbf51 before 255a758697da87a205e072e0cfc35897b8f743b1; affected 0357ef03c94ef835bd44a0658b8edb672a9dbf51 before f0edbaf487e4653a680a7abb91c1df94cb7886aa; affected 0357ef03c94ef835bd44a0658b8edb672a9dbf51 before fa5990ca8fd917003e526036bcc50413edb9722c |
| Linux / Linux | affected 6.14; unaffected 0 before 6.14; unaffected 6.18.44 through 6.18.*; unaffected 7.1.8 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/c65eb018c12179b5e2c7afe1f0956298576fecec
- https://git.kernel.org/stable/c/2bd860b7e752a51185960143cab9fec7bf32c84e
- https://git.kernel.org/stable/c/eea4b7c7711b1e425272d23352af157f45f4c3e3
- https://git.kernel.org/stable/c/2fdf8b07bee5ef99ec77773a6be05fbb8ee5cdb9
- https://git.kernel.org/stable/c/f1e7ea3c8e070f19771cdaef55bbeda1359ad490
- https://git.kernel.org/stable/c/255a758697da87a205e072e0cfc35897b8f743b1
- https://git.kernel.org/stable/c/f0edbaf487e4653a680a7abb91c1df94cb7886aa
- https://git.kernel.org/stable/c/fa5990ca8fd917003e526036bcc50413edb9722c