From: Vladimir Serbinenko <phcoder@gmail.com>
Date: Mon, 30 Jul 2012 21:42:00 +0000 (-0700)
Subject: minixfs: fix block limit check
X-Git-Tag: v3.6-rc1~41^2~38
X-Git-Url: https://repo.jachan.dev/linux.git/commitdiff_plain/6ed6a722f9ab

minixfs: fix block limit check

On minix2 and minix3 usually max_size is 7fffffff and the check in
question prohibits creation of last block spanning right before 7fffffff,
due to downward rounding during the division.  Fix it by using
multiplication instead.

[akpm@linux-foundation.org: fix up code layout, use local `sb']
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/fs/minix/itree_v2.c b/fs/minix/itree_v2.c
index 13487ad16894..78e2d93e5c83 100644
--- a/fs/minix/itree_v2.c
+++ b/fs/minix/itree_v2.c
@@ -32,7 +32,8 @@ static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
 	if (block < 0) {
 		printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n",
 			block, bdevname(sb->s_bdev, b));
-	} else if (block >= (minix_sb(inode->i_sb)->s_max_size/sb->s_blocksize)) {
+	} else if ((u64)block * (u64)sb->s_blocksize >=
+			minix_sb(sb)->s_max_size) {
 		if (printk_ratelimit())
 			printk("MINIX-fs: block_to_path: "
 			       "block %ld too big on dev %s\n",