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 134E1175A99; Mon, 17 Aug 2026 14:26:51 +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=1786976812; cv=none; b=sl6DWW40qrChOOKRP5PxEcHuntSO9qfSpDrWdYfq5xoXL0sDU5qMkLtC+7n2PHLpy7PtcOJ35WDyBFIgvmZgtUJ3dVwqV20om7j5Azmle24/16cIkHbxjvjW2wcyE2QdQF2u3+b01pWkXem/BxQJXqs93l/5wxYBsA2hul7VSmk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786976812; c=relaxed/simple; bh=RR1v0FIj+uB+NHIS0EHZBrBwmFnPUcj7FEYieVI0zfM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hYqD5qiM1fiNiiCMLaxxXdEDOG2ROsdBALJsZkRnLnDZoiq2IocKsrezCLnF/d461dohNWZcU1R1miH6jB3nK5f5sc0UoSWNZnHfREQRILChY5iFYwozKN0NxyAXbwkCX6jNKnBtxyvxis3rUrzAnMJ2W6H2g6Bwi/irHBeEkzM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=q4nmyrnM; 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="q4nmyrnM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5F4F31F000E9; Mon, 17 Aug 2026 14:26:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786976810; bh=bRgEPEDTirl+LMFFpcZZXuh7sG3Eff81BDOjHrFSn5k=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=q4nmyrnMnaT/OrSghuKAiimLwbLrJuapUwY3HpiSV2GpgXvBz9LQTXXw6QwnetzFC 051/Bm6A5OkjGIMF21qNx6D0mhM6wNOT5QAR/7QN/Hfb5qasL5sgvtlqHiMwPLgAXY STttfkCCB4qUkOkq2D6jS+l6bwuVlBuRBmTYuHPA= 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 5.15 113/456] tipc: fix infinite loop in __tipc_nl_compat_dumpit Date: Mon, 17 Aug 2026 15:28:23 +0200 Message-ID: <20260817132544.505946992@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132539.792407575@linuxfoundation.org> References: <20260817132539.792407575@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 5.15-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 116a97e301443a..a8aef355bedc67 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -226,6 +226,10 @@ 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