archive mirror
 help / color / mirror / Atom feed
From: Tetsuo Handa <>
Cc: syzbot <>,,
Subject: [PATCH] fuse: don't keep dead fuse_conn at fuse_fill_super().
Date: Wed, 9 May 2018 20:01:26 +0900	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

>From 606d54cd24b5b00e7a7e3597aabbe89719defc56 Mon Sep 17 00:00:00 2001
From: Tetsuo Handa <>
Date: Tue, 1 May 2018 13:12:14 +0900
Subject: [PATCH] fuse: don't keep dead fuse_conn at fuse_fill_super().

syzbot is reporting use-after-free at fuse_kill_sb_blk() [1].
Since sb->s_fs_info field is not cleared after fc was released by
fuse_conn_put() when initialization failed, fuse_kill_sb_blk() finds
already released fc and tries to hold the lock. Fix this by clearing
sb->s_fs_info field after calling fuse_conn_put().


Signed-off-by: Tetsuo Handa <>
Reported-by: syzbot <>
Fixes: 3b463ae0c6264f70 ("fuse: invalidation reverse calls")
Cc: John Muir <>
Cc: Csaba Henk <>
Cc: Anand Avati <>
Cc: Miklos Szeredi <>
 fs/fuse/inode.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index ef30995..9b37cf8 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -1179,6 +1179,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
+	sb->s_fs_info = NULL;

  reply	other threads:[~2018-05-09 11:01 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-30 13:34 KASAN: use-after-free Read in fuse_kill_sb_blk syzbot
2018-05-01 10:03 ` Tetsuo Handa
2018-05-09 11:01   ` Tetsuo Handa [this message]
2018-05-19 14:03     ` [PATCH] fuse: don't keep dead fuse_conn at fuse_fill_super() Tetsuo Handa
2018-05-31 10:19     ` Miklos Szeredi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \ \
    --subject='Re: [PATCH] fuse: don'\''t keep dead fuse_conn at fuse_fill_super().' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).