linux-kernel - [PATCH 5.7 040/179] btrfs: fix page leaks after failure to lock page for delalloc

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-Id: <20200727134934.628527557@linuxfoundation.org>
Date:   Mon, 27 Jul 2020 16:03:35 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Filipe Manana <fdmanana@...e.com>,
        Nikolay Borisov <nborisov@...e.com>,
        Robbie Ko <robbieko@...ology.com>,
        David Sterba <dsterba@...e.com>
Subject: [PATCH 5.7 040/179] btrfs: fix page leaks after failure to lock page for delalloc

From: Robbie Ko <robbieko@...ology.com>

commit 5909ca110b29aa16b23b52b8de8d3bb1035fd738 upstream.

When locking pages for delalloc, we check if it's dirty and mapping still
matches. If it does not match, we need to return -EAGAIN and release all
pages. Only the current page was put though, iterate over all the
remaining pages too.

CC: stable@...r.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@...e.com>
Reviewed-by: Nikolay Borisov <nborisov@...e.com>
Signed-off-by: Robbie Ko <robbieko@...ology.com>
Reviewed-by: David Sterba <dsterba@...e.com>
Signed-off-by: David Sterba <dsterba@...e.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 fs/btrfs/extent_io.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1999,7 +1999,8 @@ static int __process_pages_contig(struct
 				if (!PageDirty(pages[i]) ||
 				    pages[i]->mapping != mapping) {
 					unlock_page(pages[i]);
-					put_page(pages[i]);
+					for (; i < ret; i++)
+						put_page(pages[i]);
 					err = -EAGAIN;
 					goto out;
 				}