| From 0121afa52cdb88cfb4d5d7bd126a23a9100121d8 Mon Sep 17 00:00:00 2001 |
| From: Sven Eckelmann <sven@narfation.org> |
| Date: Mon, 6 Jul 2026 19:46:37 +0200 |
| Subject: batman-adv: dat: avoid unaligned fault in IP extraction |
| |
| From: Sven Eckelmann <sven@narfation.org> |
| |
| commit 0121afa52cdb88cfb4d5d7bd126a23a9100121d8 upstream. |
| |
| Independent of the alignment of the ARP packet in the SKB, either the |
| batadv_arp_ip_src or the batadv_arp_ip_dst will have an unaligned access |
| (on HW without native unaligned read support). |
| |
| Use get_unaligned() to handle this properly on all architectures. |
| |
| Cc: stable@vger.kernel.org |
| Reported-by: Sashiko <sashiko-bot@kernel.org> |
| Fixes: 5c3a0e553593 ("batman-adv: Distributed ARP Table - add ARP parsing functions") |
| Signed-off-by: Sven Eckelmann <sven@narfation.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/batman-adv/distributed-arp-table.c | 8 ++++++-- |
| 1 file changed, 6 insertions(+), 2 deletions(-) |
| |
| --- a/net/batman-adv/distributed-arp-table.c |
| +++ b/net/batman-adv/distributed-arp-table.c |
| @@ -250,7 +250,10 @@ static u8 *batadv_arp_hw_src(struct sk_b |
| */ |
| static __be32 batadv_arp_ip_src(struct sk_buff *skb, int hdr_size) |
| { |
| - return *(__force __be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN); |
| + u8 *src = batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN; |
| + __be32 *ip = (__force __be32 *)src; |
| + |
| + return get_unaligned(ip); |
| } |
| |
| /** |
| @@ -275,8 +278,9 @@ static u8 *batadv_arp_hw_dst(struct sk_b |
| static __be32 batadv_arp_ip_dst(struct sk_buff *skb, int hdr_size) |
| { |
| u8 *dst = batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN * 2 + 4; |
| + __be32 *ip = (__force __be32 *)dst; |
| |
| - return *(__force __be32 *)dst; |
| + return get_unaligned(ip); |
| } |
| |
| /** |
