[PATCH 6.9 140/157] nfs: fix undefined behavior in nfs_block_bits()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

6.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Sergey Shtylyov <s.shtylyov@omp.ru>

commit 3c0a2e0b0ae661457c8505fecc7be5501aa7a715 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/nfs/internal.h |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -710,9 +710,9 @@ unsigned long nfs_block_bits(unsigned lo
 	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;
 	}