lkml.org 
[lkml]   [2019]   [Oct]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH 3.16 34/87] CIFS: cifs_read_allocate_pages: don't iterate through whole page array on ENOMEM
3.16.75-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Roberto Bergantinos Corpas <rbergant@redhat.com>

commit 31fad7d41e73731f05b8053d17078638cf850fa6 upstream.

In cifs_read_allocate_pages, in case of ENOMEM, we go through
whole rdata->pages array but we have failed the allocation before
nr_pages, therefore we may end up calling put_page with NULL
pointer, causing oops

Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
fs/cifs/file.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2744,7 +2744,9 @@ cifs_read_allocate_pages(struct cifs_rea
}

if (rc) {
- for (i = 0; i < nr_pages; i++) {
+ unsigned int nr_page_failed = i;
+
+ for (i = 0; i < nr_page_failed; i++) {
put_page(rdata->pages[i]);
rdata->pages[i] = NULL;
}
\
 
 \ /
  Last update: 2019-10-02 21:13    [W:0.197 / U:55.672 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site