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 77A9044AB91; Tue, 21 Jul 2026 22:50:13 +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=1784674214; cv=none; b=nHpOp+m1rKHDEG8/NQuqeMKA/7RfshZni37+dsr2HSADWJlFmgPT3l9tA3c+WQ8IDEOoSN/RhQA7k/bt9hEKN/UErbfRIz5HrSquAba3ULCc8ZFzYDxMeaeHDgVnMYx/CqM3g1rJlNl8yEGRh3pChXivtInchIK73CgKktdF3/Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784674214; c=relaxed/simple; bh=l2L48tAGfVluZCtrq6IACEz5gN0V5sTAuxGB2ozYg9I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pBMhrr3EinsGePlqa2qRT9UP/fZ06q8rbBSJEtpiy2/17Ci4TI0+YLZd08guWa64FwUHlgEroEZ6f4TOgSptKIstk2MZ/6wPwp1bg64uhQqE661995R4muzrY5AqDj5pDab1FEyg5SeuFS5t6v+zKP3HJ6n8FHZxgHQsrrmbcPo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NexUW2ro; 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="NexUW2ro" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 82F091F00A3A; Tue, 21 Jul 2026 22:50:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784674213; bh=Ji9BZYCAcJbwHYzG9q9/j/Yn0wdWQiKeVr6WIHEC+sQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=NexUW2roXaKcPttPK98Snt7gXLrcApBy+q1IrvLpb3aeUA63ZedDl01LkRynIude2 6i21OLYnp4bmZXgFTxwUC1BHz2rqetaidaP20QeKH4BSKdxGYxiVtsJ86ppDceUBVb ynvltnQIXBhxNZ0woVrqbrl4ygLF86RpnlWlIUEA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Weiming Shi , Subash Abhinov Kasiviswanathan , Xiang Mei , Paolo Abeni , Sasha Levin Subject: [PATCH 5.10 403/699] net: qualcomm: rmnet: validate MAP frame length before ingress parsing Date: Tue, 21 Jul 2026 17:22:42 +0200 Message-ID: <20260721152404.786668682@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152355.667394603@linuxfoundation.org> References: <20260721152355.667394603@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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xiang Mei [ Upstream commit f0f1887a9e30712a1df03e152dce6fb91344b1f3 ] When ingress deaggregation is disabled, rmnet_map_ingress_handler() passes the skb straight to __rmnet_map_ingress_handler(), skipping the length validation that rmnet_map_deaggregate() performs on the aggregated path. The parser then dereferences the MAP header and csum header/trailer based on the on-wire pkt_len without checking skb->len, so a short frame is read out of bounds: BUG: KASAN: slab-out-of-bounds in rmnet_map_checksum_downlink_packet Read of size 1 at addr ffff88801118ed00 by task exploit/147 Call Trace: ... rmnet_map_checksum_downlink_packet (drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c:413) __rmnet_map_ingress_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:96) rmnet_rx_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:129) __netif_receive_skb_core.constprop.0 (net/core/dev.c:6089) netif_receive_skb (net/core/dev.c:6460) tun_get_user (drivers/net/tun.c:1955) tun_chr_write_iter (drivers/net/tun.c:2001) vfs_write (fs/read_write.c:688) ksys_write (fs/read_write.c:740) do_syscall_64 (arch/x86/entry/syscall_64.c:94) ... Factor that validation out of rmnet_map_deaggregate() into rmnet_map_validate_packet_len() and run it on the no-aggregation path too. The MAP header is bounds-checked first, since this path can receive a frame shorter than the header. Fixes: ceed73a2cf4a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation") Reported-by: Weiming Shi Suggested-by: Subash Abhinov Kasiviswanathan Signed-off-by: Xiang Mei Reviewed-by: Subash Abhinov Kasiviswanathan Link: https://patch.msgid.link/20260630174110.2003121-1-xmei5@asu.edu Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- .../ethernet/qualcomm/rmnet/rmnet_handlers.c | 5 +- .../net/ethernet/qualcomm/rmnet/rmnet_map.h | 1 + .../ethernet/qualcomm/rmnet/rmnet_map_data.c | 72 ++++++++++--------- 3 files changed, 45 insertions(+), 33 deletions(-) diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c index 9fec50a1969f14..8e5be431acaeb4 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c @@ -125,7 +125,10 @@ rmnet_map_ingress_handler(struct sk_buff *skb, consume_skb(skb); } else { - __rmnet_map_ingress_handler(skb, port); + if (rmnet_map_validate_packet_len(skb, port)) + __rmnet_map_ingress_handler(skb, port); + else + kfree_skb(skb); } } diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h index 7a2718b7e359db..dbbec14dff5cf7 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h @@ -55,5 +55,6 @@ void rmnet_map_tx_aggregate_init(struct rmnet_port *port); void rmnet_map_tx_aggregate_exit(struct rmnet_port *port); void rmnet_map_update_ul_agg_config(struct rmnet_port *port, u32 size, u32 count, u32 time); +u32 rmnet_map_validate_packet_len(struct sk_buff *skb, struct rmnet_port *port); #endif /* _RMNET_MAP_H_ */ diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c index d82af25f51cc2e..a655bb8d5c57bc 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c @@ -293,54 +293,62 @@ struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb, return map_header; } -/* Deaggregates a single packet - * A whole new buffer is allocated for each portion of an aggregated frame. - * Caller should keep calling deaggregate() on the source skb until 0 is - * returned, indicating that there are no more packets to deaggregate. Caller - * is responsible for freeing the original skb. - */ -struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb, - struct rmnet_port *port) +u32 rmnet_map_validate_packet_len(struct sk_buff *skb, struct rmnet_port *port) { struct rmnet_map_v5_csum_header *next_hdr = NULL; struct rmnet_map_header *maph; void *data = skb->data; - struct sk_buff *skbn; - u8 nexthdr_type; u32 packet_len; - if (skb->len == 0) - return NULL; + if (skb->len < sizeof(*maph)) + return 0; maph = (struct rmnet_map_header *)skb->data; + + /* Some hardware can send us empty frames. Catch them */ + if (!maph->pkt_len) + return 0; + packet_len = ntohs(maph->pkt_len) + sizeof(*maph); if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4) { packet_len += sizeof(struct rmnet_map_dl_csum_trailer); - } else if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV5) { - if (!(maph->flags & MAP_CMD_FLAG)) { - packet_len += sizeof(*next_hdr); - if (maph->flags & MAP_NEXT_HEADER_FLAG) - next_hdr = data + sizeof(*maph); - else - /* Mapv5 data pkt without csum hdr is invalid */ - return NULL; - } + } else if ((port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV5) && + !(maph->flags & MAP_CMD_FLAG)) { + /* Mapv5 data pkt without csum hdr is invalid */ + if (!(maph->flags & MAP_NEXT_HEADER_FLAG)) + return 0; + + packet_len += sizeof(*next_hdr); + next_hdr = data + sizeof(*maph); } - if (((int)skb->len - (int)packet_len) < 0) - return NULL; + if (skb->len < packet_len) + return 0; - /* Some hardware can send us empty frames. Catch them */ - if (!maph->pkt_len) - return NULL; + if (next_hdr && + u8_get_bits(next_hdr->header_info, MAPV5_HDRINFO_HDR_TYPE_FMASK) != + RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD) + return 0; - if (next_hdr) { - nexthdr_type = u8_get_bits(next_hdr->header_info, - MAPV5_HDRINFO_HDR_TYPE_FMASK); - if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD) - return NULL; - } + return packet_len; +} + +/* Deaggregates a single packet + * A whole new buffer is allocated for each portion of an aggregated frame. + * Caller should keep calling deaggregate() on the source skb until 0 is + * returned, indicating that there are no more packets to deaggregate. Caller + * is responsible for freeing the original skb. + */ +struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb, + struct rmnet_port *port) +{ + struct sk_buff *skbn; + u32 packet_len; + + packet_len = rmnet_map_validate_packet_len(skb, port); + if (!packet_len) + return NULL; skbn = alloc_skb(packet_len + RMNET_MAP_DEAGGR_SPACING, GFP_ATOMIC); if (!skbn) -- 2.53.0