linux-kernel - [PATCH 02/12] buffer: grow_dev_page() should use __GFP

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 27 Sep 2017 14:13:49 -0600
From:   Jens Axboe <axboe@...nel.dk>
To:     linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org
Cc:     hannes@...xchg.org, jack@...e.cz, torvalds@...ux-foundation.org,
        Jens Axboe <axboe@...nel.dk>
Subject: [PATCH 02/12] buffer: grow_dev_page() should use __GFP_NOFAIL for all cases

We currently it it for find_or_create_page(), which means that it
cannot fail. Ensure we also pass in 'retry == true' to
alloc_page_buffers(), which also ensure that it cannot fail.

After this, there are no failure cases in grow_dev_page() that
occur because of a failed memory allocation.

Signed-off-by: Jens Axboe <axboe@...nel.dk>
---
 fs/buffer.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index 1234ae343aef..3b60cd8456db 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -988,8 +988,6 @@ grow_dev_page(struct block_device *bdev, sector_t block,
 	gfp_mask |= __GFP_NOFAIL;
 
 	page = find_or_create_page(inode->i_mapping, index, gfp_mask);
-	if (!page)
-		return ret;
 
 	BUG_ON(!PageLocked(page));
 
@@ -1008,9 +1006,7 @@ grow_dev_page(struct block_device *bdev, sector_t block,
 	/*
 	 * Allocate some buffers for this page
 	 */
-	bh = alloc_page_buffers(page, size, false);
-	if (!bh)
-		goto failed;
+	bh = alloc_page_buffers(page, size, true);
 
 	/*
 	 * Link the page to the buffers and initialise them.  Take the
-- 
2.7.4