From: Jens Axboe <axboe@suse.de>
Date: Fri, 11 Aug 2006 20:29:11 +0000 (+0200)
Subject: Fix missing ret assignment in __bio_map_user() error path
X-Git-Tag: v2.6.16.28-rc1~5
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dec0370af02c080b1a9c240058a9887fc53a5f08;p=thirdparty%2Fkernel%2Fstable.git

Fix missing ret assignment in __bio_map_user() error path

If get_user_pages() returns less pages than what we asked for, we
jump to out_unmap which will return ERR_PTR(ret). But ret can contain
a positive number just smaller than local_nr_pages, so be sure to set
it to -EFAULT always.

Problem found and diagnosed by Damien Le Moal <damien@sdl.hitachi.co.jp>

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
---

diff --git a/fs/bio.c b/fs/bio.c
index 1f3bb501c262b..7215911464e4a 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -655,9 +655,10 @@ static struct bio *__bio_map_user_iov(request_queue_t *q,
 				     write_to_vm, 0, &pages[cur_page], NULL);
 		up_read(&current->mm->mmap_sem);
 
-		if (ret < local_nr_pages)
+		if (ret < local_nr_pages) {
+			ret = -EFAULT;
 			goto out_unmap;
-
+		}
 
 		offset = uaddr & ~PAGE_MASK;
 		for (j = cur_page; j < page_limit; j++) {