From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 B674543E08D; Thu, 30 Jul 2026 15:07:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424045; cv=none; b=Dtu6qRnSvbyfaBMTx2kLunKzm8OmlI+tUdnjDA8Jg71Fs3OAGu+md9x5nC+Dn0iI8/xDAIDl5YH9KbE4VOJu+dXRd7YwJldMj+pw9vSJYUnOgP9+D5rIq+uQN5j07OMp+10PtI+UpVsUd4GGUZQIoYjbaRTcKSuOZ2+FnicMakY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424045; c=relaxed/simple; bh=AcHE6qyNvL4+w/QLZQHs2n4EWISsO7UCtcd1Z602i9w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=spNn1Qbwe5sejGFo35k6Yq4KjEgMPM9rTPLruZg1pcQlrvH3DxKyywol3OIlYrxpeYqb+ggJdXfWt4nZAnHyZzi7079q6AMjO/KMs9R2h+TGj+BS9ijWWM3mXpNEY59o16+2Ce91trr9fMbvWmPltncGYLn3IEc9Yh0MuWN4YL8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BI58tHVC; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="BI58tHVC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0D9F11F000E9; Thu, 30 Jul 2026 15:07:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785424044; bh=EhS5z89UdSzVdI7eWnnxZOXEgvN/av6+1jYk5e6+dyU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BI58tHVCqRwQ60kzSNAckJaxNmqE3LaSuWYBVL2VYCZuPtroRFHn5f4gZKtMW5T6+ aLgB9DbJJiNq5iXH3tk4s/3JMW9mrsSaXu/0K75qhunu2/ovZzaUofmj1/iIpVugPH JOlsvnvdQgDD4i3PEc1SIFzJ7IbOM1u1s6ZC5PVo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+85d0bec020d805014a3a@syzkaller.appspotmail.com, Helen Koike , Tung Nguyen , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 255/675] tipc: fix infinite loop in __tipc_nl_compat_dumpit Date: Thu, 30 Jul 2026 16:09:45 +0200 Message-ID: <20260730141450.557688561@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@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: Helen Koike [ Upstream commit 22f8aa35964e8f2ab026578f45befc9605fd1b28 ] cmd->dumpit callback can return a negative errno, causing an infinite loop due to the while(len) condition. As the loop never terminates, genl_mutex is never released, and other tasks waiting on it starve in D state. Check dumpit's return value, propagate it and jump to err_out on error. Reported-by: syzbot+85d0bec020d805014a3a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=85d0bec020d805014a3a Fixes: d0796d1ef63d ("tipc: convert legacy nl bearer dump to nl compat") Signed-off-by: Helen Koike Reviewed-by: Tung Nguyen Link: https://patch.msgid.link/20260713204940.647668-1-koike@igalia.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/tipc/netlink_compat.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index 079aebb16ed8ff..30e37c05a3f334 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -222,6 +222,10 @@ static int __tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd, int rem; len = (*cmd->dumpit)(buf, &cb); + if (len < 0) { + err = len; + goto err_out; + } nlmsg_for_each_msg(nlmsg, nlmsg_hdr(buf), len, rem) { err = nlmsg_parse_deprecated(nlmsg, GENL_HDRLEN, -- 2.53.0