From 4208c398aae4c2290864ba15c3dab7111f32bec1 Mon Sep 17 00:00:00 2001
From: Colin Ian King <colin.king@canonical.com>
Date: Thu, 11 Feb 2021 13:01:08 +0000
Subject: [PATCH] fs/jfs: fix potential integer overflow on shift of a int
Git-commit: 4208c398aae4c2290864ba15c3dab7111f32bec1
Patch-mainline: v5.12-rc1
References: bsc#1184741
The left shift of int 32 bit integer constant 1 is evaluated using 32 bit
arithmetic and then assigned to a signed 64 bit integer. In the case where
l2nb is 32 or more this can lead to an overflow. Avoid this by shifting
the value 1LL instead.
Addresses-coverity: ("Uninitentional integer overflow")
Fixes: b40c2e665cd5 ("fs/jfs: TRIM support for JFS Filesystem")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Jan Kara <jack@suse.cz>
---
fs/jfs/jfs_dmap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 94b7c1cb5ceb..7aee15608619 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -1656,7 +1656,7 @@ s64 dbDiscardAG(struct inode *ip, int agno, s64 minlen)
} else if (rc == -ENOSPC) {
/* search for next smaller log2 block */
l2nb = BLKSTOL2(nblocks) - 1;
- nblocks = 1 << l2nb;
+ nblocks = 1LL << l2nb;
} else {
/* Trim any already allocated blocks */
jfs_error(bmp->db_ipbmap->i_sb, "-EIO\n");
--
2.26.2