4.19-stable review patch. If anyone has any objections, please let me know.
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From: Qu Wenruo wqu@suse.com
commit 5f521494cc73520ffac18ede0758883b9aedd018 upstream.
[BUG] The following script would allow invalid mount options to be specified (although such invalid options would just be ignored):
# mkfs.btrfs -f $dev # mount $dev $mnt1 <<< Successful mount expected # mount $dev $mnt2 -o junk <<< Failed mount expected # echo $? 0
[CAUSE] For the 2nd mount, since the fs is already mounted, we won't go through open_ctree() thus no btrfs_parse_options(), but only through btrfs_parse_subvol_options().
However we do not treat unrecognized options from valid but irrelevant options, thus those invalid options would just be ignored by btrfs_parse_subvol_options().
[FIX] Add the handling for Opt_err to handle invalid options and error out, while still ignore other valid options inside btrfs_parse_subvol_options().
Reported-by: Anand Jain anand.jain@oracle.com CC: stable@vger.kernel.org # 4.14+ Signed-off-by: Qu Wenruo wqu@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/super.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -991,6 +991,10 @@ static int btrfs_parse_subvol_options(co case Opt_subvolrootid: pr_warn("BTRFS: 'subvolrootid' mount option is deprecated and has no effect\n"); break; + case Opt_err: + btrfs_err(NULL, "unrecognized mount option '%s'", p); + error = -EINVAL; + goto out; default: break; }