Netdev Archive on lore.kernel.org
help / color / mirror / Atom feed
From: yajun.deng@linux.dev
To: m.szyprowski@samsung.com
Cc: davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Fwd: Re: [PATCH] net: convert fib_treeref from int to refcount_t
Date: Tue, 03 Aug 2021 11:17:59 +0000	[thread overview]
Message-ID: <7177b79774f6be76431ff4af9fa164f8@linux.dev> (raw)
In-Reply-To: <2033809a-1a07-1f5d-7732-f10f6e094f3d@gmail.com>

[-- Attachment #1: Type: text/plain, Size: 697 bytes --]

This patch from David Ahern was applied in the newest net-next.

-------- Forwarded message -------
From: "David Ahern" <dsahern@gmail.com>
To: "Ioana Ciornei" <ciorneiioana@gmail.com>, "Yajun Deng" <yajun.deng@linux.dev>
CC: davem@davemloft.net, kuba@kernel.org, yoshfuji@linux-ipv6.org, dsahern@kernel.org,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-decnet-user@lists.sourceforge.net
Sent: August 2, 2021 10:36 PM
Subject: Re: [PATCH] net: convert fib_treeref from int to refcount_t
On 8/2/21 7:37 AM, Ioana Ciornei wrote:

> Unfortunately, with this patch applied I get into the following WARNINGs
> when booting over NFS:

Can you test the attached?

Thanks,

[-- Attachment #2: 0001-ipv4-Fix-refcount-warning-for-new-fib_info.patch --]
[-- Type: application/octet-stream, Size: 1680 bytes --]

From ec9d169eb33e6a65db641792821cc6a259ed9362 Mon Sep 17 00:00:00 2001
From: David Ahern <dsahern@kernel.org>
Date: Mon, 2 Aug 2021 08:29:26 -0600
Subject: [PATCH net-next] ipv4: Fix refcount warning for new fib_info

Ioana reported a refcount warning when booting over NFS:

[    5.042532] ------------[ cut here ]------------
[    5.047184] refcount_t: addition on 0; use-after-free.
[    5.052324] WARNING: CPU: 7 PID: 1 at lib/refcount.c:25 refcount_warn_saturate+0xa4/0x150
...
[    5.167201] Call trace:
[    5.169635]  refcount_warn_saturate+0xa4/0x150
[    5.174067]  fib_create_info+0xc00/0xc90
[    5.177982]  fib_table_insert+0x8c/0x620
[    5.181893]  fib_magic.isra.0+0x110/0x11c
[    5.185891]  fib_add_ifaddr+0xb8/0x190
[    5.189629]  fib_inetaddr_event+0x8c/0x140

fib_treeref needs to be set after kzalloc. The old code had a ++ which
led to the confusion when the int was replaced by a refcount_t.

Fixes: 79976892f7ea ("net: convert fib_treeref from int to refcount_t")
Signed-off-by: David Ahern <dsahern@kernel.org>
Reported-by: Ioana Ciornei <ciorneiioana@gmail.com>
Cc: Yajun Deng <yajun.deng@linux.dev>
---
 net/ipv4/fib_semantics.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index fa19f4cdf3a4..f29feb7772da 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -1551,7 +1551,7 @@ struct fib_info *fib_create_info(struct fib_config *cfg,
 		return ofi;
 	}
 
-	refcount_inc(&fi->fib_treeref);
+	refcount_set(&fi->fib_treeref, 1);
 	refcount_set(&fi->fib_clntref, 1);
 	spin_lock_bh(&fib_info_lock);
 	hlist_add_head(&fi->fib_hash,
-- 
2.24.3 (Apple Git-128)


  parent reply	other threads:[~2021-08-03 11:18 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-29  7:13 Yajun Deng
2021-07-29 14:55 ` David Ahern
2021-07-30 15:30 ` patchwork-bot+netdevbpf
2021-08-02 13:37 ` Ioana Ciornei
2021-08-02 14:36   ` David Ahern
2021-08-02 14:59     ` Ioana Ciornei
2021-08-03 11:17   ` yajun.deng [this message]
2021-08-03 11:24     ` Fwd: " Marek Szyprowski
     [not found] ` <CGME20210803110803eucas1p276a0010caad8fc21a7ea5ca5543294f8@eucas1p2.samsung.com>
2021-08-03 11:08   ` Marek Szyprowski
2021-08-03 14:43     ` David Ahern

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:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

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

  git send-email \
    --in-reply-to=7177b79774f6be76431ff4af9fa164f8@linux.dev \
    --to=yajun.deng@linux.dev \
    --cc=davem@davemloft.net \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=m.szyprowski@samsung.com \
    --cc=netdev@vger.kernel.org \
    --subject='Fwd: Re: [PATCH] net: convert fib_treeref from int to refcount_t' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* 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
on how to clone and mirror all data and code used for this inbox