jbd2: If a journal checksum error is detected, propagate the error to ext4

If a journal checksum error is detected, the ext4 filesystem will call
ext4_error(), and the mount will either continue, become a read-only
mount, or cause a kernel panic based on the superblock flags
indicating the user's preference of what to do in case of filesystem
corruption being detected.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 23 insertions, 0 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 09d9359c8055..d01a32e8b50a 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2189,6 +2189,29 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent)
             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
                 if (ext4_load_journal(sb, es, journal_devnum))
                         goto failed_mount3;
+                if (!(sb->s_flags & MS_RDONLY) &&
+                    EXT4_SB(sb)->s_journal->j_failed_commit) {
+                        printk(KERN_CRIT "EXT4-fs error (device %s): "
+                               "ext4_fill_super: Journal transaction "
+                               "%u is corrupt\n", sb->s_id, 
+                               EXT4_SB(sb)->s_journal->j_failed_commit);
+                        if (test_opt (sb, ERRORS_RO)) {
+                                printk (KERN_CRIT
+                                        "Mounting filesystem read-only\n");
+                                sb->s_flags |= MS_RDONLY;
+                                EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
+                                es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
+                        }
+                        if (test_opt(sb, ERRORS_PANIC)) {
+                                EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
+                                es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
+                                ext4_commit_super(sb, es, 1);
+                                printk(KERN_CRIT
+                                       "EXT4-fs (device %s): mount failed\n",
+                                      sb->s_id);
+                                goto failed_mount4;
+                        }
+                }
         } else if (journal_inum) {
                 if (ext4_create_journal(sb, es, journal_inum))
                         goto failed_mount3;