From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ABAE433E377; Mon, 20 Apr 2026 16:03:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776701000; cv=none; b=Jz5pwWGorhM7dnb040pGlk0iCUyLuVuY4uNsV1zODSDO3hachX6DKt2Su0AtSRQpc3PdcQhLGifbwTwmudzPQvUPJ6EtjVyoTn3nqWjaEUZpMwHhmuw1CB/qY3G/Zlk39mHO1k9OzuaD56IdxNqJjUauOBO7UuW2Mp0BDJAMoM0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776701000; c=relaxed/simple; bh=JSJIU2d0JNPo40IoZpmLqZPYHWB6t6epXvMi5+QIiH8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SR6yfpDdIkfbSw3HJ33i+8tb5CrcXALrpF7GwnQDVVb6HS/1ZNd0P9YcdtcMU99sOuOVD98k+J0aHu8IMIq65NlAlRL/CJHHwlroPTpXxNGql0aUMt6uKcWbWmG0BluM6HqgC+vfX32x+/1c9IZwMrUlutWYO+M2wzuLdHGATF0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=exmDfI24; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="exmDfI24" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41AD1C2BCB6; Mon, 20 Apr 2026 16:03:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776701000; bh=JSJIU2d0JNPo40IoZpmLqZPYHWB6t6epXvMi5+QIiH8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=exmDfI24TK/Rg979x0hiL8jqPDB7QGfL6wt/N5YDw+/2daMnfM2lu/ZG2bom6C03J MuBsaiRkF7SPLBQUuXK4vyjhWUqV6ny/QZpDr+PE002uP6g0amdrCjqee2bx+ZEDnh 8+GAhjZ8QTVeqeg4DWfzsBpf0K83yQKDMGbaxpEk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yifan Wu , Juefei Pu , Yuan Tan , Xin Liu , Ren Wei , Jiexun Wang , Ren Wei , Kuniyuki Iwashima , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 109/198] af_unix: read UNIX_DIAG_VFS data under unix_state_lock Date: Mon, 20 Apr 2026 17:41:28 +0200 Message-ID: <20260420153939.528976911@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260420153935.605963767@linuxfoundation.org> References: <20260420153935.605963767@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiexun Wang [ Upstream commit 39897df386376912d561d4946499379effa1e7ef ] Exact UNIX diag lookups hold a reference to the socket, but not to u->path. Meanwhile, unix_release_sock() clears u->path under unix_state_lock() and drops the path reference after unlocking. Read the inode and device numbers for UNIX_DIAG_VFS while holding unix_state_lock(), then emit the netlink attribute after dropping the lock. This keeps the VFS data stable while the reply is being built. Fixes: 5f7b0569460b ("unix_diag: Unix inode info NLA") Reported-by: Yifan Wu Reported-by: Juefei Pu Co-developed-by: Yuan Tan Signed-off-by: Yuan Tan Suggested-by: Xin Liu Tested-by: Ren Wei Signed-off-by: Jiexun Wang Signed-off-by: Ren Wei Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260407080015.1744197-1-n05ec@lzu.edu.cn Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/unix/diag.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/net/unix/diag.c b/net/unix/diag.c index ca34730261510..c9c1e51c44196 100644 --- a/net/unix/diag.c +++ b/net/unix/diag.c @@ -28,18 +28,23 @@ static int sk_diag_dump_name(struct sock *sk, struct sk_buff *nlskb) static int sk_diag_dump_vfs(struct sock *sk, struct sk_buff *nlskb) { - struct dentry *dentry = unix_sk(sk)->path.dentry; + struct unix_diag_vfs uv; + struct dentry *dentry; + bool have_vfs = false; + unix_state_lock(sk); + dentry = unix_sk(sk)->path.dentry; if (dentry) { - struct unix_diag_vfs uv = { - .udiag_vfs_ino = d_backing_inode(dentry)->i_ino, - .udiag_vfs_dev = dentry->d_sb->s_dev, - }; - - return nla_put(nlskb, UNIX_DIAG_VFS, sizeof(uv), &uv); + uv.udiag_vfs_ino = d_backing_inode(dentry)->i_ino; + uv.udiag_vfs_dev = dentry->d_sb->s_dev; + have_vfs = true; } + unix_state_unlock(sk); - return 0; + if (!have_vfs) + return 0; + + return nla_put(nlskb, UNIX_DIAG_VFS, sizeof(uv), &uv); } static int sk_diag_dump_peer(struct sock *sk, struct sk_buff *nlskb) -- 2.53.0