sb_start_write() will be returning error for a shutdown filesystem.
Teach all ovl_start_write() to handle the error and bail out.
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
fs/overlayfs/copy_up.c | 42 +++++++++++++++++++++++++++++++---------
fs/overlayfs/overlayfs.h | 2 +-
fs/overlayfs/util.c | 3 ++-
3 files changed, 36 insertions(+), 11 deletions(-)
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index a5ef2005a2cc..6ebfd9c7b260 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -584,7 +584,9 @@ static int ovl_link_up(struct ovl_copy_up_ctx *c)
struct ovl_fs *ofs = OVL_FS(c->dentry->d_sb);
struct inode *udir = d_inode(upperdir);
- ovl_start_write(c->dentry);
+ err = ovl_start_write(c->dentry);
+ if (err)
+ return err;
/* Mark parent "impure" because it may now contain non-pure upper */
err = ovl_set_impure(c->parent, upperdir);
@@ -744,6 +746,7 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
struct path path = { .mnt = ovl_upper_mnt(ofs) };
struct dentry *temp, *upper, *trap;
struct ovl_cu_creds cc;
+ bool frozen = false;
int err;
struct ovl_cattr cattr = {
/* Can't properly set mode on creation because of the umask */
@@ -756,7 +759,11 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
if (err)
return err;
- ovl_start_write(c->dentry);
+ err = ovl_start_write(c->dentry);
+ if (err) {
+ ovl_revert_cu_creds(&cc);
+ return err;
+ }
inode_lock(wdir);
temp = ovl_create_temp(ofs, c->workdir, &cattr);
inode_unlock(wdir);
@@ -778,7 +785,10 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
* ovl_copy_up_data(), so lock workdir and destdir and make sure that
* temp wasn't moved before copy up completion or cleanup.
*/
- ovl_start_write(c->dentry);
+ if (!err) {
+ err = ovl_start_write(c->dentry);
+ frozen = !err;
+ }
trap = lock_rename(c->workdir, c->destdir);
if (trap || temp->d_parent != c->workdir) {
/* temp or workdir moved underneath us? abort without cleanup */
@@ -827,7 +837,8 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
unlock:
unlock_rename(c->workdir, c->destdir);
out:
- ovl_end_write(c->dentry);
+ if (frozen)
+ ovl_end_write(c->dentry);
return err;
@@ -851,7 +862,11 @@ static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c)
if (err)
return err;
- ovl_start_write(c->dentry);
+ err = ovl_start_write(c->dentry);
+ if (err) {
+ ovl_revert_cu_creds(&cc);
+ return err;
+ }
tmpfile = ovl_do_tmpfile(ofs, c->workdir, c->stat.mode);
ovl_end_write(c->dentry);
ovl_revert_cu_creds(&cc);
@@ -865,7 +880,9 @@ static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c)
goto out_fput;
}
- ovl_start_write(c->dentry);
+ err = ovl_start_write(c->dentry);
+ if (err)
+ goto out_fput;
err = ovl_copy_up_metadata(c, temp);
if (err)
@@ -964,7 +981,9 @@ static int ovl_do_copy_up(struct ovl_copy_up_ctx *c)
* Mark parent "impure" because it may now contain non-pure
* upper
*/
- ovl_start_write(c->dentry);
+ err = ovl_start_write(c->dentry);
+ if (err)
+ goto out_free_fh;
err = ovl_set_impure(c->parent, c->destdir);
ovl_end_write(c->dentry);
if (err)
@@ -982,7 +1001,9 @@ static int ovl_do_copy_up(struct ovl_copy_up_ctx *c)
if (c->indexed)
ovl_set_flag(OVL_INDEX, d_inode(c->dentry));
- ovl_start_write(c->dentry);
+ err = ovl_start_write(c->dentry);
+ if (err)
+ goto out;
if (to_index) {
/* Initialize nlink for copy up of disconnected dentry */
err = ovl_set_nlink_upper(c->dentry);
@@ -1088,7 +1109,10 @@ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
* Writing to upper file will clear security.capability xattr. We
* don't want that to happen for normal copy-up operation.
*/
- ovl_start_write(c->dentry);
+ err = ovl_start_write(c->dentry);
+ if (err)
+ goto out_free;
+
if (capability) {
err = ovl_do_setxattr(ofs, upperpath.dentry, XATTR_NAME_CAPS,
capability, cap_size, 0);
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 0bfe35da4b7b..ee8f2b28159a 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -423,7 +423,7 @@ static inline int ovl_do_getattr(const struct path *path, struct kstat *stat,
/* util.c */
int ovl_get_write_access(struct dentry *dentry);
void ovl_put_write_access(struct dentry *dentry);
-void ovl_start_write(struct dentry *dentry);
+int __must_check ovl_start_write(struct dentry *dentry);
void ovl_end_write(struct dentry *dentry);
int ovl_want_write(struct dentry *dentry);
void ovl_drop_write(struct dentry *dentry);
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index edc9216f6e27..b53fa14506a9 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -25,10 +25,11 @@ int ovl_get_write_access(struct dentry *dentry)
}
/* Get write access to upper sb - may block if upper sb is frozen */
-void ovl_start_write(struct dentry *dentry)
+int __must_check ovl_start_write(struct dentry *dentry)
{
struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
sb_start_write(ovl_upper_mnt(ofs)->mnt_sb);
+ return 0;
}
int ovl_want_write(struct dentry *dentry)
--
2.35.3
