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 <artemiyv@xxxxxxx>
---
A quick fix to v1 which wrongly uses spaces instead of tabs.
e2fsck/pass1.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index 0a8e23e..71ea943 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -482,6 +482,10 @@ 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_size >= max - sizeof(__u32))
+ return;
+
eamagic = (__u32 *) (((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
inode->i_extra_isize);
if (*eamagic == EXT2_EXT_ATTR_MAGIC) {
--
1.7.10.4
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