ext4: apply umask if ACL support is disabled

MaxKellermann · tytso · commit 484fd6c1de13 · 2023-10-05T22:32:15.000-04:00
The function ext4_init_acl() calls posix_acl_create() which is responsible for applying the umask. But without CONFIG_EXT4_FS_POSIX_ACL, ext4_init_acl() is an empty inline function, and nobody applies the umask. This fixes a bug which causes the umask to be ignored with O_TMPFILE on ext4: MusicPlayerDaemon/MPD#558 https://bugs.gentoo.org/show_bug.cgi?id=686142#c3 https://bugzilla.kernel.org/show_bug.cgi?id=203625 Reviewed-by: "J. Bruce Fields" <bfields@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Max Kellermann <max.kellermann@ionos.com> Link: https://lore.kernel.org/r/20230919081824.1096619-1-max.kellermann@ionos.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/acl.h b/fs/ext4/acl.h
@@ -68,6 +68,11 @@ extern int ext4_init_acl(handle_t *, struct inode *, struct inode *);
 static inline int
 ext4_init_acl(handle_t *handle, struct inode *inode, struct inode *dir)
 {
+	/* usually, the umask is applied by posix_acl_create(), but if
+	   ext4 ACL support is disabled at compile time, we need to do
+	   it here, because posix_acl_create() will never be called */
+	inode->i_mode &= ~current_umask();
+
 	return 0;
 }
 #endif  /* CONFIG_EXT4_FS_POSIX_ACL */

Original file line number	Diff line number	Diff line change
`@@ -68,6 +68,11 @@ extern int ext4_init_acl(handle_t , struct inode , struct inode *);`
`68`	`68`	`static inline int`
`69`	`69`	`ext4_init_acl(handle_t handle, struct inode inode, struct inode *dir)`
`70`	`70`	`{`
	`71`	`+ /* usually, the umask is applied by posix_acl_create(), but if`
	`72`	`+ ext4 ACL support is disabled at compile time, we need to do`
	`73`	`+ it here, because posix_acl_create() will never be called */`
	`74`	`+ inode->i_mode &= ~current_umask();`
	`75`	`+`
`71`	`76`	`return 0;`
`72`	`77`	`}`
`73`	`78`	`#endif /* CONFIG_EXT4_FS_POSIX_ACL */`