diff options
| -rw-r--r-- | fs/overlayfs/overlayfs.h | 9 | ||||
| -rw-r--r-- | fs/overlayfs/ovl_entry.h | 1 | ||||
| -rw-r--r-- | fs/overlayfs/super.c | 10 |
3 files changed, 20 insertions, 0 deletions
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 8af450b0e57a..3822a909ce1f 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -127,6 +127,15 @@ static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry) return err; } +static inline struct dentry *ovl_do_tmpfile(struct dentry *dentry, umode_t mode) +{ + struct dentry *ret = vfs_tmpfile(dentry, mode, 0); + int err = IS_ERR(ret) ? PTR_ERR(ret) : 0; + + pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err); + return ret; +} + static inline struct inode *ovl_inode_real(struct inode *inode, bool *is_upper) { unsigned long x = (unsigned long) READ_ONCE(inode->i_private); diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h index d14bca1850d9..65f240001aa6 100644 --- a/fs/overlayfs/ovl_entry.h +++ b/fs/overlayfs/ovl_entry.h @@ -27,6 +27,7 @@ struct ovl_fs { struct ovl_config config; /* creds of process who forced instantiation of super block */ const struct cred *creator_cred; + bool tmpfile; }; /* private information held for every overlayfs dentry */ diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 20f48abbb82f..ff05065b510f 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -825,6 +825,8 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) * creation of workdir in previous step. */ if (ufs->workdir) { + struct dentry *temp; + err = ovl_check_d_type_supported(&workpath); if (err < 0) goto out_put_workdir; @@ -836,6 +838,14 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) */ if (!err) pr_warn("overlayfs: upper fs needs to support d_type.\n"); + + /* Check if upper/work fs supports O_TMPFILE */ + temp = ovl_do_tmpfile(ufs->workdir, S_IFREG | 0); + ufs->tmpfile = !IS_ERR(temp); + if (ufs->tmpfile) + dput(temp); + else + pr_warn("overlayfs: upper fs does not support tmpfile.\n"); } } |