From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Subject: fs/hfs/extent.c: fix array out of bounds read of array extent
Currently extent and index i are both being incremented causing an array
out of bounds read on extent[i]. Fix this by removing the extraneous
increment of extent.
Ernesto said:
: This is only triggered when deleting a file with a resource fork. I
: may be wrong because the documentation isn't clear, but I don't think
: you can create those under linux. So I guess nobody was testing them.
:
: > A disk space leak, perhaps?
:
: That's what it looks like in general. hfs_free_extents() won't do
: anything if the block count doesn't add up, and the error will be
: ignored. Now, if the block count randomly does add up, we could see
: some corruption.
Detected by CoverityScan, CID#711541 ("Out of bounds read")
Link: http://lkml.kernel.org/r/20180831140538.31566-1-colin.king@xxxxxxxxxxxxx
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Reviewed-by: Ernesto A. Fernndez <ernesto.mnd.fernandez@xxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Hin-Tak Leung <htl10@xxxxxxxxxxxxxxxxxxxxx>
Cc: Vyacheslav Dubeyko <slava@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/hfs/extent.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/hfs/extent.c~hfs-fix-array-out-of-bounds-read-of-array-extent
+++ a/fs/hfs/extent.c
@@ -304,7 +304,7 @@ int hfs_free_fork(struct super_block *sb
return 0;
blocks = 0;
- for (i = 0; i < 3; extent++, i++)
+ for (i = 0; i < 3; i++)
blocks += be16_to_cpu(extent[i].count);
res = hfs_free_extents(sb, extent, blocks, blocks);
_
