nfs: fix undefined behavior in nfs_block_bits()
Shifting *signed int* typed constant 1 left by 31 bits causes undefined
behavior. Specify the correct *unsigned long* type by using 1UL instead.
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
Cc: stable@vger.kernel.org
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index dc0693b..9f0f453 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -717,9 +717,9 @@
if ((bsize & (bsize - 1)) || nrbitsp) {
unsigned char nrbits;
- for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
+ for (nrbits = 31; nrbits && !(bsize & (1UL << nrbits)); nrbits--)
;
- bsize = 1 << nrbits;
+ bsize = 1UL << nrbits;
if (nrbitsp)
*nrbitsp = nrbits;
}
