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 320F4429097; Sat, 28 Feb 2026 17:46:32 +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=1772300792; cv=none; b=YmG60ICS+Q+OIm+gBLp+cFoQQ0Bi5dVwCxs9oTQJ4Ea7dZ6FV4hFXgo3gD5vLe6bqReaoObC/xIVSq7JXuCSwT1oM0PunR6BW//hHMB9gRvPv9cIRYQ1+EXY5dPiBM++JNWgpEoRGpr6ac5ZQdQvMXTwKo6sW3SvdUPfiNCWiw4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772300792; c=relaxed/simple; bh=UyULersl7ZgEjSJZEV+xxB3ZkP0sOWni99ZT4GmK+ac=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LWA2sHOVUfd5gy59MSXK0p7sxYxpG3EkDXnFU2CaW2iHsV53Oudqg+WJGXMF+X+oLCRIZGxzLP+3vKUZ+oaFYDX8r0znfLM9r7sw76LkmyVgFCOPvLUlEV8GeW4eEjj++8iImbq68HOw4RgoQgw6aK26IYAf7ERjMEWOuc0xOJE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BGbpVDAR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BGbpVDAR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77536C19425; Sat, 28 Feb 2026 17:46:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772300792; bh=UyULersl7ZgEjSJZEV+xxB3ZkP0sOWni99ZT4GmK+ac=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BGbpVDARoBel6C/ycM9bU223fZQezqvw7GQzl6Ny535p59ua3VumRvHMLBPkZio9w Jd4NrvfQo9CCEuPKTnml+ZZ/KHgmufE4CGPqt2saGKg13lo8HvGeNndX51EK+wvFuj fZnoA49Xil9CquW1UT3J+HfdO8epYAay2hGUbM+jwTKCAPWEgZ/C5cXadr78LS8H3v KEGxu822JtAkZ1H7UdJDBaR10sSpFzoelOa/jePQFBENcD+3sg/8702hHUNrH1d0Fi O9XMtJW6TaGhqeNak5QAqgnYKQuHL7dekhFaKP1GJXN/pBcdRguDYuPa4yR/xjYUFd qDnH8vSso7nSA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ruitong Liu , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.19 824/844] net/sched: act_skbedit: fix divide-by-zero in tcf_skbedit_hash() Date: Sat, 28 Feb 2026 12:32:17 -0500 Message-ID: <20260228173244.1509663-825-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228173244.1509663-1-sashal@kernel.org> References: <20260228173244.1509663-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Ruitong Liu [ Upstream commit be054cc66f739a9ba615dba9012a07fab8e7dd6f ] Commit 38a6f0865796 ("net: sched: support hash selecting tx queue") added SKBEDIT_F_TXQ_SKBHASH support. The inclusive range size is computed as: mapping_mod = queue_mapping_max - queue_mapping + 1; The range size can be 65536 when the requested range covers all possible u16 queue IDs (e.g. queue_mapping=0 and queue_mapping_max=U16_MAX). That value cannot be represented in a u16 and previously wrapped to 0, so tcf_skbedit_hash() could trigger a divide-by-zero: queue_mapping += skb_get_hash(skb) % params->mapping_mod; Compute mapping_mod in a wider type and reject ranges larger than U16_MAX to prevent params->mapping_mod from becoming 0 and avoid the crash. Fixes: 38a6f0865796 ("net: sched: support hash selecting tx queue") Cc: stable@vger.kernel.org # 6.12+ Signed-off-by: Ruitong Liu Link: https://patch.msgid.link/20260213175948.1505257-1-cnitlrt@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/act_skbedit.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c index 8c1d1554f6575..5450c1293eb50 100644 --- a/net/sched/act_skbedit.c +++ b/net/sched/act_skbedit.c @@ -126,7 +126,7 @@ static int tcf_skbedit_init(struct net *net, struct nlattr *nla, struct tcf_skbedit *d; u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL; u16 *queue_mapping = NULL, *ptype = NULL; - u16 mapping_mod = 1; + u32 mapping_mod = 1; bool exists = false; int ret = 0, err; u32 index; @@ -194,6 +194,10 @@ static int tcf_skbedit_init(struct net *net, struct nlattr *nla, } mapping_mod = *queue_mapping_max - *queue_mapping + 1; + if (mapping_mod > U16_MAX) { + NL_SET_ERR_MSG_MOD(extack, "The range of queue_mapping is invalid."); + return -EINVAL; + } flags |= SKBEDIT_F_TXQ_SKBHASH; } if (*pure_flags & SKBEDIT_F_INHERITDSFIELD) -- 2.51.0