diff mbox series

[v2,01/15] SUNRPC: _shift_data_left/right_pages should check the shift length

Message ID 20201211172521.5567-2-trondmy@kernel.org (mailing list archive)
State New, archived
Headers show
Series Fixes for the NFSv4.2 READ_PLUS operation | expand

Commit Message

Trond Myklebust Dec. 11, 2020, 5:25 p.m. UTC 
From: Trond Myklebust <trond.myklebust@hammerspace.com>

Exit early if the shift is zero.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)
diff mbox series

Patch

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index c852d199c789..5833329c132c 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -225,6 +225,9 @@  _shift_data_left_pages(struct page **pages, size_t pgto_base,
 
 	BUG_ON(pgfrom_base <= pgto_base);
 
+	if (!len)
+		return;
+
 	pgto = pages + (pgto_base >> PAGE_SHIFT);
 	pgfrom = pages + (pgfrom_base >> PAGE_SHIFT);
 
@@ -307,6 +310,9 @@  _shift_data_right_pages(struct page **pages, size_t pgto_base,
 
 	BUG_ON(pgto_base <= pgfrom_base);
 
+	if (!len)
+		return;
+
 	pgto_base += len;
 	pgfrom_base += len;
 
@@ -405,6 +411,9 @@  _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len)
 	char *vto;
 	size_t copy;
 
+	if (!len)
+		return;
+
 	pgto = pages + (pgbase >> PAGE_SHIFT);
 	pgbase &= ~PAGE_MASK;
 
@@ -449,6 +458,9 @@  _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
 	char *vfrom;
 	size_t copy;
 
+	if (!len)
+		return;
+
 	pgfrom = pages + (pgbase >> PAGE_SHIFT);
 	pgbase &= ~PAGE_MASK;