From 2b833c9aae3323745af3fdc998d8b3255f40511e Mon Sep 17 00:00:00 2001 From: Artemiy Volkov Date: Mon, 30 Nov 2015 12:03:52 -0500 Subject: [PATCH] e2fsck: do not read EA header beyond the end of an inode In check_inode_extra_space(), if we attempt to read an EA header at the end of the extra space, in a corrupted filesystem it may result in a read beyond the bounds of the inode. Add a check to prevent this. Reproduced by running ./test_one --valgrind f_write_ea_toobig_extra_isize. Signed-off-by: Artemiy Volkov Signed-off-by: Theodore Ts'o Acked-by: Darrick J. Wong --- e2fsck/pass1.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c index ac3ea4eb..66ff69a3 100644 --- a/e2fsck/pass1.c +++ b/e2fsck/pass1.c @@ -382,6 +382,10 @@ static void check_inode_extra_space(e2fsck_t ctx, struct problem_context *pctx) return; } + /* check if there is no place for an EA header */ + if (inode->i_extra_isize >= max - sizeof(__u32)) + return; + eamagic = (__u32 *) (((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE + inode->i_extra_isize); if (*eamagic == EXT2_EXT_ATTR_MAGIC) {