diff options
author | Hugh Dickins <hughd@google.com> | 2023-08-09 07:30:59 +0300 |
---|---|---|
committer | Christian Brauner <brauner@kernel.org> | 2023-08-09 10:15:51 +0300 |
commit | 5de75970c9fd7220e394b76e6d20fbafa1369b5a (patch) | |
tree | eb0b3a67a96b975840c0600a70cbbf4dab39d0fc /mm/shmem.c | |
parent | 0200679fc7953177941e41c2a4241d0b6c2c5de8 (diff) | |
download | linux-5de75970c9fd7220e394b76e6d20fbafa1369b5a.tar.xz |
xattr: simple_xattr_set() return old_xattr to be freed
tmpfs wants to support limited user extended attributes, but kernfs
(or cgroupfs, the only kernfs with KERNFS_ROOT_SUPPORT_USER_XATTR)
already supports user extended attributes through simple xattrs: but
limited by a policy (128KiB per inode) too liberal to be used on tmpfs.
To allow a different limiting policy for tmpfs, without affecting the
policy for kernfs, change simple_xattr_set() to return the replaced or
removed xattr (if any), leaving the caller to update their accounting
then free the xattr (by simple_xattr_free(), renamed from the static
free_simple_xattr()).
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Message-Id: <158c6585-2aa7-d4aa-90ff-f7c3f8fe407c@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'mm/shmem.c')
-rw-r--r-- | mm/shmem.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 678a7be46b89..b22d0bf1f5e3 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -3598,15 +3598,17 @@ static int shmem_xattr_handler_set(const struct xattr_handler *handler, size_t size, int flags) { struct shmem_inode_info *info = SHMEM_I(inode); - int err; + struct simple_xattr *old_xattr; name = xattr_full_name(handler, name); - err = simple_xattr_set(&info->xattrs, name, value, size, flags, NULL); - if (!err) { + old_xattr = simple_xattr_set(&info->xattrs, name, value, size, flags); + if (!IS_ERR(old_xattr)) { + simple_xattr_free(old_xattr); + old_xattr = NULL; inode->i_ctime = current_time(inode); inode_inc_iversion(inode); } - return err; + return PTR_ERR(old_xattr); } static const struct xattr_handler shmem_security_xattr_handler = { |