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 A986E2C11F9; Thu, 28 May 2026 20:20:41 +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=1779999642; cv=none; b=LntqmslCs3Bu1ba3pYCoVyivWoQWe5nbMKDy7hKIhFgAEKt4bH+78dMPrfNh8nFh2uU4O5MuTEVoZrgqf5DKsytp/qo85EVBBcKQYoDrmRQ2RHzYZoIA9WH2HJHTuYD5qpc+1AVkq3lRhqrAEfqQFESi+IA/59bZe4toAAzydq0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779999642; c=relaxed/simple; bh=EXcqi0nKgRfX8qzt5rljRavkrSE5Hp72l8kTnWKspek=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VHoZZA9SssZiM/c/zM7lrL5tQZFL/EilN12hxp2oUrHTNWJPAoGniJ+1BsrFccnCANXFdjY7zBr53INS35DfsHCr7yIYXUx8via13R75GHpxx87Uv5D9THNhkv9M+7XjOyw9sa0odX7p1FzKWa9v4BS+78O3dFzGK2GUFLQH9DU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=gbufpTrH; 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="gbufpTrH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1ACC71F000E9; Thu, 28 May 2026 20:20:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779999641; bh=qKLbPB6I9iKHPCkE++WrYjXxiMuPvS9SggWbzMs7wzQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=gbufpTrHkmWthlg9BCfMn2G+PfGag0St+tD5RGbumJoVR7YnkyyOMVKoO3eoKfiGP vRksLtGEtucsJDFFSyNDhc706LpXY2W//l+Bf9ru+foUW1RqxAdllI7okBy8h9bYtF IhrVM8x6pIojwzahoUI16Gfcp4FnzxuDQpURfCmw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, Yuan Tan , Yifan Wu , Juefei Pu , Xin Liu , Sven Eckelmann Subject: [PATCH 6.18 139/377] batman-adv: tvlv: reject oversized TVLV packets Date: Thu, 28 May 2026 21:46:17 +0200 Message-ID: <20260528194642.397844154@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260528194638.371537336@linuxfoundation.org> References: <20260528194638.371537336@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org 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: Sven Eckelmann commit f50487e3566358b2b982b7801945e858c78ad9ab upstream. batadv_tvlv_container_ogm_append() builds a TVLV packet section from the tvlv.container_list. The total size of this section is computed by batadv_tvlv_container_list_size(), which sums the sizes of all registered containers. The return type and accumulator in batadv_tvlv_container_list_size() were u16. If the accumulated size exceeds U16_MAX, the value wraps around, causing the subsequent allocation in batadv_tvlv_container_ogm_append() to be undersized. The memcpy-style copy that follows would then write beyond the end of the allocated buffer, corrupting kernel memory. Fix this by widening the return type of batadv_tvlv_container_list_size() to size_t. In batadv_tvlv_container_ogm_append(), check the computed length against U16_MAX before proceeding, and bail out as if the allocation had failed when the limit is exceeded. Cc: stable@kernel.org Fixes: ef26157747d4 ("batman-adv: tvlv - basic infrastructure") Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Reviewed-by: Yuan Tan Signed-off-by: Sven Eckelmann Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/tvlv.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) --- a/net/batman-adv/tvlv.c +++ b/net/batman-adv/tvlv.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -160,10 +161,10 @@ batadv_tvlv_container_get(struct batadv_ * * Return: size of all currently registered tvlv containers in bytes. */ -static u16 batadv_tvlv_container_list_size(struct batadv_priv *bat_priv) +static size_t batadv_tvlv_container_list_size(struct batadv_priv *bat_priv) { struct batadv_tvlv_container *tvlv; - u16 tvlv_len = 0; + size_t tvlv_len = 0; lockdep_assert_held(&bat_priv->tvlv.container_list_lock); @@ -316,13 +317,17 @@ int batadv_tvlv_container_ogm_append(str { struct batadv_tvlv_container *tvlv; struct batadv_tvlv_hdr *tvlv_hdr; - u16 tvlv_value_len; + size_t tvlv_value_len; void *tvlv_value; int tvlv_len_ret; bool ret; spin_lock_bh(&bat_priv->tvlv.container_list_lock); tvlv_value_len = batadv_tvlv_container_list_size(bat_priv); + if (tvlv_value_len > U16_MAX) { + tvlv_len_ret = -E2BIG; + goto end; + } ret = batadv_tvlv_realloc_packet_buff(packet_buff, packet_buff_len, packet_min_len, tvlv_value_len);