[Ocfs2-tools-devel] [PATCH] tunefs.ocfs2: fix a potential overflowing problem in check_new_size

[piaojun]

Potentially overflowing expression "0xffffffffU << b_to_c_bits" with
type "unsigned int" (32 bits, unsigned) is evaluated using 32-bit
arithmetic before being used in a context which expects an expression
of type "uint64_t" (64 bits, unsigned). To avoid overflow, cast the left
operand to "uint64_t" before performing the left shift.

Fixes: 15f01d8d8c1c ("tunefs.ocfs2: Warn if not using complete device")

Signed-off-by: Jun Piao <piaojun at huawei.com>
---
 tunefs.ocfs2/op_resize_volume.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tunefs.ocfs2/op_resize_volume.c b/tunefs.ocfs2/op_resize_volume.c
index 076bda0..84d8628 100644
--- a/tunefs.ocfs2/op_resize_volume.c
+++ b/tunefs.ocfs2/op_resize_volume.c
@@ -543,7 +543,7 @@ static errcode_t check_new_size(ocfs2_filesys *fs, uint64_t new_size,
 				 "Clusters (%"PRIu64" is greater than "
 				 "maximum possible clusters %"PRIu32"\n",
 				 device_clusters, UINT32_MAX);
-			try_blocks = UINT32_MAX << b_to_c_bits;
+			try_blocks = (uint64_t)UINT32_MAX << b_to_c_bits;
 			errorf("Clusters %"PRIu64" is greater than max allowed"
 			       " %"PRIu32".\nIf you want to resize to %"PRIu64
 			       " blocks please specify %"PRIu64" as "
-- 
1.8.4.3