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 8AFB930567C; Thu, 30 Jul 2026 15:37:03 +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=1785425824; cv=none; b=Ny2l/EnWa9JIbjI0KksBBcnZMSNmCRMt+hEeVqkexNI+PX3zYFk4D0VGQryoAp2E9gb3LKmOhslte6xlhHcntWzO3QzMAIj9O2pYLWRRo7lg0LM5qut+ugKYJIUphrQEhyYwFzsdRKaBDAG2CONV8pCLDFbU9boBteostxqEn94= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785425824; c=relaxed/simple; bh=VXFINMyqcLRatsLJG2ejoyqCIwpAGfTL0wGo6NmV0Fs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Dy9oRqZ9g1KKPRozZjMH5pSOAGkQTYo6OQofl/JgsgCx6F/DZOvjRedv4SbX2Uv/JSMxMk+vRBv1zORjlGgusMaMPswo59jolaNEqy4qS2q9tSgcFTxOCG1gaKOC2t18t8uCV87vpEI5OaZlnqwFQ/VkCrC4VPWvffUxuk+4+Ks= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yKQglbyy; 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="yKQglbyy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E4DF81F000E9; Thu, 30 Jul 2026 15:37:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785425823; bh=vhRQIWx1Hu8hmHjEg5N7vPXnc5n4zQsiUD4de87rSg0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=yKQglbyyDm3pVOU+kmT+8acecwDXNSsMo3hfAMU4KbRQPAU8WFQ5Zb9ZqKo1atE+y f19adwmj9qWq17/uvtw0DTWHM0jI4FHNJWaANHkeoQfSRskrqnISYEbriw+Bcw3DsS gml+AkpR2cS8Q1ato66auSlSWpq0eyhz9kJcJVAo= 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 6.12 204/602] tipc: fix infinite loop in __tipc_nl_compat_dumpit Date: Thu, 30 Jul 2026 16:09:56 +0200 Message-ID: <20260730141440.244241233@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141435.976815864@linuxfoundation.org> References: <20260730141435.976815864@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 6.12-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