From: David Howells <dhowells@redhat.com>
Date: Fri, 11 May 2007 05:22:19 +0000 (-0700)
Subject: AFS: fix interminable loop in afs_write_back_from_locked_page()
X-Git-Tag: v2.6.22-rc1~98
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9d577b6a31a53a19d3b0fe414d645a61ef201846;p=linux-2.6

AFS: fix interminable loop in afs_write_back_from_locked_page()

Following bug was uncovered by compiling with '-W' flag:

  CC [M]  fs/afs/write.o
fs/afs/write.c: In function ‘afs_write_back_from_locked_page’:
fs/afs/write.c:398: warning: comparison of unsigned expression >= 0 is always true

Loop variable 'n' is unsigned, so wraps around happily as far as I can
see. Trival fix attached (compile tested only).

Signed-off-by: Mika Kukkonen <mikukkon@iki.fi>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/fs/afs/write.c b/fs/afs/write.c
index 67ae4dbf66..28f37516c1 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -395,8 +395,9 @@ static int afs_write_back_from_locked_page(struct afs_writeback *wb,
 		if (n == 0)
 			goto no_more;
 		if (pages[0]->index != start) {
-			for (n--; n >= 0; n--)
-				put_page(pages[n]);
+			do {
+				put_page(pages[--n]);
+			} while (n > 0);
 			goto no_more;
 		}