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 7359E1494DA; Fri, 29 Mar 2024 12:29:01 +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=1711715341; cv=none; b=PgAKlW6dBdNn/AnOneGnG+CnsTMCciP47QvGt1PNUeXdOoe8b/eUYpnLiwo1jWtB+LmSMZaohkwXnX+2ylkqEFC9+JTn5LLRJAKaxulRcCmSEnefCF+OIk0K9CCWP9aRfXTJa1lA25vMoYyRbpBM1FSeh4y0Qt5YVWq+LW19pA8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711715341; c=relaxed/simple; bh=VBbr5zV+DGiCnpCpxIGYBmWTVXJfvphyBATaBXAmY8w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YiJNsYADNvd/QmYdBfvohMZqrCuW4lFTKr5sTMKetUvWSvK/q3uhxtYBqfVYByN4tyK39wyZVQHdtxpd9+wqomkh8Z7CFBvsaueT/QLWfn7scb3ZOAIXxPur9Dbf3YIp+W/EmH4c2HfgSMX/ILcYluWDJvpmoHdaykm5DYL5/Gs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nA1ttXm9; 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="nA1ttXm9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19BA0C433A6; Fri, 29 Mar 2024 12:29:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711715341; bh=VBbr5zV+DGiCnpCpxIGYBmWTVXJfvphyBATaBXAmY8w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nA1ttXm9PKt3XZj729XZD22+k9T98SG4dFAnpAo9Iey9W72Ip38tn5P7f3PjEUwAp Pkid58TI2m2FKLxK1lwH/HFU1eZqEY9NSVWN2FOqlDriA/tm3Y+z8X1IemCLW07XZt 7QdXTEtSokD9Qf1HcPFt8Pj3pDCK7lcEqCt/xo2idkDUynIg7SqzOTRnWnn6auv9wc qYMVZXuSTMkAS6WVFi7Eeni8n2WsIPgc91+Mcgj86ANrVsMXn6KoCadYd3c5ffxm1v GSyHZ5f0/M+byGTr+CQ0nbuINpQBbvk6nd15hWuPbL3mJ275J/tdo803sWs/5pd7ws BvEs6h/XaVfAw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Johannes Berg , syzbot+d050d437fe47d479d210@syzkaller.appspotmail.com, Sasha Levin , johannes@sipsolutions.net, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 6.8 58/68] wifi: cfg80211: check A-MSDU format more carefully Date: Fri, 29 Mar 2024 08:25:54 -0400 Message-ID: <20240329122652.3082296-58-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240329122652.3082296-1-sashal@kernel.org> References: <20240329122652.3082296-1-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 X-stable-base: Linux 6.8.2 Content-Transfer-Encoding: 8bit From: Johannes Berg [ Upstream commit 9ad7974856926129f190ffbe3beea78460b3b7cc ] If it looks like there's another subframe in the A-MSDU but the header isn't fully there, we can end up reading data out of bounds, only to discard later. Make this a bit more careful and check if the subframe header can even be present. Reported-by: syzbot+d050d437fe47d479d210@syzkaller.appspotmail.com Link: https://msgid.link/20240226203405.a731e2c95e38.I82ce7d8c0cc8970ce29d0a39fdc07f1ffc425be4@changeid Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/wireless/util.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index d1ce3bee27973..b9d15f369378b 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -791,15 +791,19 @@ ieee80211_amsdu_subframe_length(void *field, u8 mesh_flags, u8 hdr_type) bool ieee80211_is_valid_amsdu(struct sk_buff *skb, u8 mesh_hdr) { - int offset = 0, remaining, subframe_len, padding; + int offset = 0, subframe_len, padding; for (offset = 0; offset < skb->len; offset += subframe_len + padding) { + int remaining = skb->len - offset; struct { __be16 len; u8 mesh_flags; } hdr; u16 len; + if (sizeof(hdr) > remaining) + return false; + if (skb_copy_bits(skb, offset + 2 * ETH_ALEN, &hdr, sizeof(hdr)) < 0) return false; @@ -807,7 +811,6 @@ bool ieee80211_is_valid_amsdu(struct sk_buff *skb, u8 mesh_hdr) mesh_hdr); subframe_len = sizeof(struct ethhdr) + len; padding = (4 - subframe_len) & 0x3; - remaining = skb->len - offset; if (subframe_len > remaining) return false; @@ -825,7 +828,7 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, { unsigned int hlen = ALIGN(extra_headroom, 4); struct sk_buff *frame = NULL; - int offset = 0, remaining; + int offset = 0; struct { struct ethhdr eth; uint8_t flags; @@ -839,10 +842,14 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, copy_len = sizeof(hdr); while (!last) { + int remaining = skb->len - offset; unsigned int subframe_len; int len, mesh_len = 0; u8 padding; + if (copy_len > remaining) + goto purge; + skb_copy_bits(skb, offset, &hdr, copy_len); if (iftype == NL80211_IFTYPE_MESH_POINT) mesh_len = __ieee80211_get_mesh_hdrlen(hdr.flags); @@ -852,7 +859,6 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, padding = (4 - subframe_len) & 0x3; /* the last MSDU has no padding */ - remaining = skb->len - offset; if (subframe_len > remaining) goto purge; /* mitigate A-MSDU aggregation injection attacks */ -- 2.43.0