diff options
| author | Zilin Guan <zilin@seu.edu.cn> | 2025-11-05 02:29:23 +0000 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2025-11-05 14:00:16 +0100 |
| commit | 90f601b497d76f40fa66795c3ecf625b6aced9fd (patch) | |
| tree | 9b0c9869cd10acee9c1fc71f817df2b1d8554e2b | |
| parent | c014021253d77cd89b2d8788ce522283d83fbd40 (diff) | |
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.
Fixes: e7850f4d844e ("binfmt_misc: fix possible deadlock in bm_register_write")
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Link: https://patch.msgid.link/20251105022923.1813587-1-zilin@seu.edu.cn
Signed-off-by: Christian Brauner <brauner@kernel.org>
| -rw-r--r-- | fs/binfmt_misc.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c index a839f960cd4a..a8b1d79e4af0 100644 --- a/fs/binfmt_misc.c +++ b/fs/binfmt_misc.c @@ -837,8 +837,10 @@ out: inode_unlock(d_inode(root)); if (err) { - if (f) + if (f) { + exe_file_allow_write_access(f); filp_close(f, NULL); + } kfree(e); return err; } |