diff mbox series

[net,v2] netfilter: xt_recent: fix (increase) ipv6 literal buffer length

Message ID 20231105195600.522779-1-maze@google.com
State Accepted
Headers show
Series [net,v2] netfilter: xt_recent: fix (increase) ipv6 literal buffer length | expand

Commit Message

Maciej Żenczykowski Nov. 5, 2023, 7:56 p.m. UTC 
From: Maciej Żenczykowski <zenczykowski@gmail.com>

in6_pton() supports 'low-32-bit dot-decimal representation'
(this is useful with DNS64/NAT64 networks for example):

  # echo +aaaa:bbbb:cccc:dddd:eeee:ffff:1.2.3.4 > /proc/self/net/xt_recent/DEFAULT
  # cat /proc/self/net/xt_recent/DEFAULT
  src=aaaa:bbbb:cccc:dddd:eeee:ffff:0102:0304 ttl: 0 last_seen: 9733848829 oldest_pkt: 1 9733848829

but the provided buffer is too short:

  # echo +aaaa:bbbb:cccc:dddd:eeee:ffff:255.255.255.255 > /proc/self/net/xt_recent/DEFAULT
  -bash: echo: write error: Invalid argument

Cc: Jan Engelhardt <jengelh@inai.de>
Cc: Patrick McHardy <kaber@trash.net>
Fixes: 079aa88fe717 ("netfilter: xt_recent: IPv6 support")
Signed-off-by: Maciej Żenczykowski <zenczykowski@gmail.com>
---
 net/netfilter/xt_recent.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Simon Horman Nov. 7, 2023, 5:11 p.m. UTC | #1 
On Sun, Nov 05, 2023 at 11:56:00AM -0800, Maciej Żenczykowski wrote:
> From: Maciej Żenczykowski <zenczykowski@gmail.com>
> 
> in6_pton() supports 'low-32-bit dot-decimal representation'
> (this is useful with DNS64/NAT64 networks for example):
> 
>   # echo +aaaa:bbbb:cccc:dddd:eeee:ffff:1.2.3.4 > /proc/self/net/xt_recent/DEFAULT
>   # cat /proc/self/net/xt_recent/DEFAULT
>   src=aaaa:bbbb:cccc:dddd:eeee:ffff:0102:0304 ttl: 0 last_seen: 9733848829 oldest_pkt: 1 9733848829
> 
> but the provided buffer is too short:
> 
>   # echo +aaaa:bbbb:cccc:dddd:eeee:ffff:255.255.255.255 > /proc/self/net/xt_recent/DEFAULT
>   -bash: echo: write error: Invalid argument
> 
> Cc: Jan Engelhardt <jengelh@inai.de>
> Cc: Patrick McHardy <kaber@trash.net>
> Fixes: 079aa88fe717 ("netfilter: xt_recent: IPv6 support")
> Signed-off-by: Maciej Żenczykowski <zenczykowski@gmail.com>

Reviewed-by: Simon Horman <horms@kernel.org>
diff mbox series

Patch

diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c
index 7ddb9a78e3fc..ef93e0d3bee0 100644
--- a/net/netfilter/xt_recent.c
+++ b/net/netfilter/xt_recent.c
@@ -561,7 +561,7 @@  recent_mt_proc_write(struct file *file, const char __user *input,
 {
 	struct recent_table *t = pde_data(file_inode(file));
 	struct recent_entry *e;
-	char buf[sizeof("+b335:1d35:1e55:dead:c0de:1715:5afe:c0de")];
+	char buf[sizeof("+b335:1d35:1e55:dead:c0de:1715:255.255.255.255")];
 	const char *c = buf;
 	union nf_inet_addr addr = {};
 	u_int16_t family;