+ lib-radix-treec-fix-overflow-in-radix_tree_range_tag_if_tagged.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     lib/radix-tree.c: fix overflow in radix_tree_range_tag_if_tagged()
has been added to the -mm tree.  Its filename is
     lib-radix-treec-fix-overflow-in-radix_tree_range_tag_if_tagged.patch

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------------------------------------------------------
Subject: lib/radix-tree.c: fix overflow in radix_tree_range_tag_if_tagged()
From: Jan Kara <jack@suse.cz>

When radix_tree_maxindex() is ~0UL, it can happen that scanning
overflows index and tree traversal code goes astray reading memory
until it hits unreadable memory. Check for overflow and exit in
that case.

Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/radix-tree.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff -puN lib/radix-tree.c~lib-radix-treec-fix-overflow-in-radix_tree_range_tag_if_tagged lib/radix-tree.c
--- a/lib/radix-tree.c~lib-radix-treec-fix-overflow-in-radix_tree_range_tag_if_tagged
+++ a/lib/radix-tree.c
@@ -675,7 +675,8 @@ unsigned long radix_tree_range_tag_if_ta
 next:
 		/* Go to next item at level determined by 'shift' */
 		index = ((index >> shift) + 1) << shift;
-		if (index > last_index)
+		/* Overflow can happen when last_index is ~0UL... */
+		if (index > last_index || !index)
 			break;
 		if (tagged >= nr_to_tag)
 			break;
_

Patches currently in -mm which might be from jack@suse.cz are

origin.patch
lib-radix-treec-fix-overflow-in-radix_tree_range_tag_if_tagged.patch
aio-do-not-return-erestartsys-and-friends-from-aio.patch
reiser4.patch