If ext4_fill_super() failed after extents status shrinker has been registered, the shrinker is left in a global list while the memory, it sits in, is already freed. Oops is not so bad scenario after that. Found by Linux File System Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx> --- fs/ext4/super.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 5d6d5357..5f9cb30 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3757,7 +3757,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) && !(sb->s_flags & MS_RDONLY)) if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block))) - goto failed_mount3; + goto failed_mount_shr; /* * The first inode we look at is the journal inode. Don't try @@ -3766,7 +3766,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) if (!test_opt(sb, NOLOAD) && EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) { if (ext4_load_journal(sb, es, journal_devnum)) - goto failed_mount3; + goto failed_mount_shr; } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) && EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) { ext4_msg(sb, KERN_ERR, "required journal recovery " @@ -4009,6 +4009,8 @@ failed_mount_wq: jbd2_journal_destroy(sbi->s_journal); sbi->s_journal = NULL; } +failed_mount_shr: + ext4_es_unregister_shrinker(sb); failed_mount3: del_timer(&sbi->s_err_report); if (sbi->s_flex_groups) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html