From: David Carlier Date: Sat, 4 Apr 2026 13:47:47 +0000 (+0100) Subject: tracefs: Fix default permissions not being applied on initial mount X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e8368d1f4bedbb0cce4cfe33a1d2664bb0fd4f27;p=thirdparty%2Fkernel%2Flinux.git tracefs: Fix default permissions not being applied on initial mount Commit e4d32142d1de ("tracing: Fix tracefs mount options") moved the option application from tracefs_fill_super() to tracefs_reconfigure() called from tracefs_get_tree(). This fixed mount options being ignored on user-space mounts when the superblock already exists, but introduced a regression for the initial kernel-internal mount. On the first mount (via simple_pin_fs during init), sget_fc() transfers fc->s_fs_info to sb->s_fs_info and sets fc->s_fs_info to NULL. When tracefs_get_tree() then calls tracefs_reconfigure(), it sees a NULL fc->s_fs_info and returns early without applying any options. The root inode keeps mode 0755 from simple_fill_super() instead of the intended TRACEFS_DEFAULT_MODE (0700). Furthermore, even on subsequent user-space mounts without an explicit mode= option, tracefs_apply_options(sb, true) gates the mode behind fsi->opts & BIT(Opt_mode), which is unset for the defaults. So the mode is never corrected unless the user explicitly passes mode=0700. Restore the tracefs_apply_options(sb, false) call in tracefs_fill_super() to apply default permissions on initial superblock creation, matching what debugfs does in debugfs_fill_super(). Cc: stable@vger.kernel.org Fixes: e4d32142d1de ("tracing: Fix tracefs mount options") Link: https://patch.msgid.link/20260404134747.98867-1-devnexen@gmail.com Signed-off-by: David Carlier Signed-off-by: Steven Rostedt (Google) --- diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c index fa4c7e6aa5fff..5602baf980f68 100644 --- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -468,6 +468,7 @@ static int tracefs_fill_super(struct super_block *sb, struct fs_context *fc) return err; sb->s_op = &tracefs_super_operations; + tracefs_apply_options(sb, false); set_default_d_op(sb, &tracefs_dentry_operations); return 0;