6.16-stable review patch. If anyone has any objections, please let me know.
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From: Yuntao Wang yuntao.wang@linux.dev
[ Upstream commit 593d9e4c3d634c370f226f55453c376bf43b3684 ]
The lflags value used to look up from_path was overwritten by the one used to look up to_path.
In other words, from_path was looked up with the wrong lflags value. Fix it.
Fixes: f9fde814de37 ("fs: support getname_maybe_null() in move_mount()") Signed-off-by: Yuntao Wang yuntao.wang@linux.dev Link: https://lore.kernel.org/20250811052426.129188-1-yuntao.wang@linux.dev [Christian Brauner brauner@kernel.org: massage patch] Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/namespace.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-)
diff --git a/fs/namespace.c b/fs/namespace.c index ea724ad3d113..49d016711469 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -4657,20 +4657,10 @@ SYSCALL_DEFINE5(move_mount, if (flags & MOVE_MOUNT_SET_GROUP) mflags |= MNT_TREE_PROPAGATION; if (flags & MOVE_MOUNT_BENEATH) mflags |= MNT_TREE_BENEATH;
- lflags = 0; - if (flags & MOVE_MOUNT_F_SYMLINKS) lflags |= LOOKUP_FOLLOW; - if (flags & MOVE_MOUNT_F_AUTOMOUNTS) lflags |= LOOKUP_AUTOMOUNT; uflags = 0; - if (flags & MOVE_MOUNT_F_EMPTY_PATH) uflags = AT_EMPTY_PATH; - from_name = getname_maybe_null(from_pathname, uflags); - if (IS_ERR(from_name)) - return PTR_ERR(from_name); + if (flags & MOVE_MOUNT_T_EMPTY_PATH) + uflags = AT_EMPTY_PATH;
- lflags = 0; - if (flags & MOVE_MOUNT_T_SYMLINKS) lflags |= LOOKUP_FOLLOW; - if (flags & MOVE_MOUNT_T_AUTOMOUNTS) lflags |= LOOKUP_AUTOMOUNT; - uflags = 0; - if (flags & MOVE_MOUNT_T_EMPTY_PATH) uflags = AT_EMPTY_PATH; to_name = getname_maybe_null(to_pathname, uflags); if (IS_ERR(to_name)) return PTR_ERR(to_name); @@ -4683,11 +4673,24 @@ SYSCALL_DEFINE5(move_mount, to_path = fd_file(f_to)->f_path; path_get(&to_path); } else { + lflags = 0; + if (flags & MOVE_MOUNT_T_SYMLINKS) + lflags |= LOOKUP_FOLLOW; + if (flags & MOVE_MOUNT_T_AUTOMOUNTS) + lflags |= LOOKUP_AUTOMOUNT; ret = filename_lookup(to_dfd, to_name, lflags, &to_path, NULL); if (ret) return ret; }
+ uflags = 0; + if (flags & MOVE_MOUNT_F_EMPTY_PATH) + uflags = AT_EMPTY_PATH; + + from_name = getname_maybe_null(from_pathname, uflags); + if (IS_ERR(from_name)) + return PTR_ERR(from_name); + if (!from_name && from_dfd >= 0) { CLASS(fd_raw, f_from)(from_dfd); if (fd_empty(f_from)) @@ -4696,6 +4699,11 @@ SYSCALL_DEFINE5(move_mount, return vfs_move_mount(&fd_file(f_from)->f_path, &to_path, mflags); }
+ lflags = 0; + if (flags & MOVE_MOUNT_F_SYMLINKS) + lflags |= LOOKUP_FOLLOW; + if (flags & MOVE_MOUNT_F_AUTOMOUNTS) + lflags |= LOOKUP_AUTOMOUNT; ret = filename_lookup(from_dfd, from_name, lflags, &from_path, NULL); if (ret) return ret;