From 78f1ddbb498283c2445c11b0dfa666424c301803 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 27 Jul 2009 23:09:47 -0400 Subject: [PATCH] ext4: Avoid null pointer dereference when decoding EROFS w/o a journal We need to check to make sure a journal is present before checking the journal flags in ext4_decode_error(). Signed-off-by: Eric Sesterhenn Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 8f4f079e6b9a..fe3f376b7df2 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -344,7 +344,8 @@ static const char *ext4_decode_error(struct super_block *sb, int errno, errstr = "Out of memory"; break; case -EROFS: - if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT) + if (!sb || (EXT4_SB(sb)->s_journal && + EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)) errstr = "Journal has aborted"; else errstr = "Readonly filesystem"; -- 2.20.1