linux-kernel - [PATCH 5.6 047/166] f2fs: fix to avoid potential deadlock

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]

Date:   Wed, 22 Apr 2020 11:56:14 +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, Chao Yu <yuchao0@...wei.com>,
        Jaegeuk Kim <jaegeuk@...nel.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.6 047/166] f2fs: fix to avoid potential deadlock

From: Chao Yu <yuchao0@...wei.com>

[ Upstream commit df77fbd8c5b222c680444801ffd20e8bbc90a56e ]

Using f2fs_trylock_op() in f2fs_write_compressed_pages() to avoid potential
deadlock like we did in f2fs_write_single_data_page().

Signed-off-by: Chao Yu <yuchao0@...wei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 fs/f2fs/compress.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index d8a64be90a501..c847523ab4a2e 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -772,7 +772,6 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 		.encrypted_page = NULL,
 		.compressed_page = NULL,
 		.submitted = false,
-		.need_lock = LOCK_RETRY,
 		.io_type = io_type,
 		.io_wbc = wbc,
 		.encrypted = f2fs_encrypted_file(cc->inode),
@@ -785,9 +784,10 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 	loff_t psize;
 	int i, err;
 
-	set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
+	if (!f2fs_trylock_op(sbi))
+		return -EAGAIN;
 
-	f2fs_lock_op(sbi);
+	set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
 
 	err = f2fs_get_dnode_of_data(&dn, start_idx, LOOKUP_NODE);
 	if (err)
-- 
2.20.1