From: Theodore Ts'o <tytso@mit.edu>
Date: Tue, 28 Jul 2009 03:09:47 +0000 (-0400)
Subject: ext4: Avoid null pointer dereference when decoding EROFS w/o a journal
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=78f1ddbb498283c2445c11b0dfa666424c301803;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

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

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";