linux-kernel - [PATCH 3.15 2/2] f2fs: check bdi->dirty_exceeded when trying to skip data writes

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:	Mon, 14 Jul 2014 07:52:51 -0700
From:	Jaegeuk Kim <jaegeuk@...nel.org>
To:	linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
	linux-f2fs-devel@...ts.sourceforge.net, stable@...r.kernel.org
Cc:	Jaegeuk Kim <jaegeuk@...nel.org>
Subject: [PATCH 3.15 2/2] f2fs: check bdi->dirty_exceeded when trying to skip data writes

commit dd6b9bf5883c3ca9c17bac80ccd8615fe5a452a3 upstream.

If we don't check the current backing device status, balance_dirty_pages can
fall into infinite pausing routine.

This can be occurred when a lot of directories make a small number of dirty
dentry pages including files.

Reported-by: Brian Chadwick <brianchad@...tnet.com.au>
Signed-off-by: Jaegeuk Kim <jaegeuk@...nel.org>
---
 fs/f2fs/node.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index a9c0495..5696bde 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -42,6 +42,8 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type)
 		mem_size = (nm_i->nat_cnt * sizeof(struct nat_entry)) >> 12;
 		res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 2);
 	} else if (type == DIRTY_DENTS) {
+		if (sbi->sb->s_bdi->dirty_exceeded)
+			return false;
 		mem_size = get_pages(sbi, F2FS_DIRTY_DENTS);
 		res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 1);
 	}
-- 
2.0.1.472.g6f92e5f

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/