From 4208c398aae4c2290864ba15c3dab7111f32bec1 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Thu, 11 Feb 2021 13:01:08 +0000 Subject: [PATCH] fs/jfs: fix potential integer overflow on shift of a int 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 Signed-off-by: Dave Kleikamp --- 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");