4.14-stable review patch. If anyone has any objections, please let me know.
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From: Eric Sandeen sandeen@redhat.com
[ Upstream commit 0d9366d67bcf066b028e57d09c9a86ce879bcc28 ]
If mount is auto-probing for filesystem type, it will try various filesystems in order, with the MS_SILENT flag set. We get that flag as the silent arg to ext4_fill_super.
If we're probing (silent==1) then don't complain about feature incompatibilities that are found if it looks like it's actually a different valid extN type - failed probes should be silent in this case.
If the on-disk features are unknown even to ext4, then complain.
Reported-by: Joakim Tjernlund Joakim.Tjernlund@infinera.com Tested-by: Joakim Tjernlund Joakim.Tjernlund@infinera.com Signed-off-by: Eric Sandeen sandeen@redhat.com Signed-off-by: Theodore Ts'o tytso@mit.edu Reviewed-by: Jan Kara jack@suse.cz Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ext4/super.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
--- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3663,6 +3663,12 @@ static int ext4_fill_super(struct super_ ext4_msg(sb, KERN_INFO, "mounting ext2 file system " "using the ext4 subsystem"); else { + /* + * If we're probing be silent, if this looks like + * it's actually an ext[34] filesystem. + */ + if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb))) + goto failed_mount; ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due " "to feature incompatibilities"); goto failed_mount; @@ -3674,6 +3680,12 @@ static int ext4_fill_super(struct super_ ext4_msg(sb, KERN_INFO, "mounting ext3 file system " "using the ext4 subsystem"); else { + /* + * If we're probing be silent, if this looks like + * it's actually an ext4 filesystem. + */ + if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb))) + goto failed_mount; ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due " "to feature incompatibilities"); goto failed_mount;