diff options
Diffstat (limited to 'fs/overlayfs/super.c')
| -rw-r--r-- | fs/overlayfs/super.c | 38 |
1 files changed, 31 insertions, 7 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 2bd570cbe8a4..d58b8f2bf9d0 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -264,11 +264,20 @@ static int ovl_sync_fs(struct super_block *sb, int wait) struct super_block *upper_sb; int ret; - if (!ovl_upper_mnt(ofs)) - return 0; + ret = ovl_sync_status(ofs); + /* + * We have to always set the err, because the return value isn't + * checked in syncfs, and instead indirectly return an error via + * the sb's writeback errseq, which VFS inspects after this call. + */ + if (ret < 0) { + errseq_set(&sb->s_wb_err, -EIO); + return -EIO; + } + + if (!ret) + return ret; - if (!ovl_should_sync(ofs)) - return 0; /* * Not called for sync(2) call or an emergency sync (SB_I_SKIP_SYNC). * All the super blocks will be iterated, including upper_sb. @@ -1923,6 +1932,10 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) unsigned int numlower; int err; + err = -EIO; + if (WARN_ON(sb->s_user_ns != current_user_ns())) + goto out; + sb->s_d_op = &ovl_dentry_operations; err = -ENOMEM; @@ -1989,6 +2002,8 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) sb->s_op = &ovl_super_operations; if (ofs->config.upperdir) { + struct super_block *upper_sb; + if (!ofs->config.workdir) { pr_err("missing 'workdir'\n"); goto out_err; @@ -1998,6 +2013,16 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) if (err) goto out_err; + upper_sb = ovl_upper_mnt(ofs)->mnt_sb; + if (!ovl_should_sync(ofs)) { + ofs->errseq = errseq_sample(&upper_sb->s_wb_err); + if (errseq_check(&upper_sb->s_wb_err, ofs->errseq)) { + err = -EIO; + pr_err("Cannot mount volatile when upperdir has an unseen error. Sync upperdir fs to clear state.\n"); + goto out_err; + } + } + err = ovl_get_workdir(sb, ofs, &upperpath); if (err) goto out_err; @@ -2005,9 +2030,8 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) if (!ofs->workdir) sb->s_flags |= SB_RDONLY; - sb->s_stack_depth = ovl_upper_mnt(ofs)->mnt_sb->s_stack_depth; - sb->s_time_gran = ovl_upper_mnt(ofs)->mnt_sb->s_time_gran; - + sb->s_stack_depth = upper_sb->s_stack_depth; + sb->s_time_gran = upper_sb->s_time_gran; } oe = ovl_get_lowerstack(sb, splitlower, numlower, ofs, layers); err = PTR_ERR(oe); |