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13 Commits

Author SHA1 Message Date
Jan Engelhardt 37e55cf0ce netfilter: xt_recent: fix stack overread in compat code
Related-to: commit 325fb5b4d2

The compat path suffers from a similar problem. It only uses a __be32
when all of the recent code uses, and expects, an nf_inet_addr
everywhere. As a result, addresses stored by xt_recents were
filled with whatever other stuff was on the stack following the be32.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

With a minor compile fix from Roman.

Reported-and-tested-by: Roman Hoog Antink <rha@open.ch>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-04-24 17:05:21 +02:00
Josef Drexler 325fb5b4d2 netfilter: xt_recent: fix proc-file addition/removal of IPv4 addresses
Fix regression introduded by commit 079aa88 (netfilter: xt_recent: IPv6 support):

From http://bugzilla.kernel.org/show_bug.cgi?id=12753:

Problem Description:
An uninitialized buffer causes IPv4 addresses added manually (via the +IP
command to the proc interface) to never match any packets. Similarly, the -IP
command fails to remove IPv4 addresses.

Details:
In the function recent_entry_lookup, the xt_recent module does comparisons of
the entire nf_inet_addr union value, both for IPv4 and IPv6 addresses. For
addresses initialized from actual packets the remaining 12 bytes not occupied
by the IPv4 are zeroed so this works correctly. However when setting the
nf_inet_addr addr variable in the recent_mt_proc_write function, only the IPv4
bytes are initialized and the remaining 12 bytes contain garbage.

Hence addresses added in this way never match any packets, unless these
uninitialized 12 bytes happened to be zero by coincidence. Similarly, addresses
cannot consistently be removed using the proc interface due to mismatch of the
garbage bytes (although it will sometimes work to remove an address that was
added manually).

Reading the /proc/net/xt_recent/ entries hides this problem because this only
uses the first 4 bytes when displaying IPv4 addresses.

Steps to reproduce:
$ iptables -I INPUT -m recent --rcheck -j LOG
$ echo +169.254.156.239 > /proc/net/xt_recent/DEFAULT
$ cat /proc/net/xt_recent/DEFAULT
src=169.254.156.239 ttl: 0 last_seen: 119910 oldest_pkt: 1 119910

[At this point no packets from 169.254.156.239 are being logged.]

$ iptables -I INPUT -s 169.254.156.239 -m recent --set
$ cat /proc/net/xt_recent/DEFAULT
src=169.254.156.239 ttl: 0 last_seen: 119910 oldest_pkt: 1 119910
src=169.254.156.239 ttl: 255 last_seen: 126184 oldest_pkt: 4 125434, 125684, 125934, 126184

[At this point, adding the address via an iptables rule, packets are being
logged correctly.]

$ echo -169.254.156.239 > /proc/net/xt_recent/DEFAULT
$ cat /proc/net/xt_recent/DEFAULT
src=169.254.156.239 ttl: 0 last_seen: 119910 oldest_pkt: 1 119910
src=169.254.156.239 ttl: 255 last_seen: 126992 oldest_pkt: 10 125434, 125684, 125934, 126184, 126434, 126684, 126934, 126991, 126991, 126992
$ echo -169.254.156.239 > /proc/net/xt_recent/DEFAULT
$ cat /proc/net/xt_recent/DEFAULT
src=169.254.156.239 ttl: 0 last_seen: 119910 oldest_pkt: 1 119910
src=169.254.156.239 ttl: 255 last_seen: 126992 oldest_pkt: 10 125434, 125684, 125934, 126184, 126434, 126684, 126934, 126991, 126991, 126992

[Removing the address via /proc interface failed evidently.]

Possible solutions:
- initialize the addr variable in recent_mt_proc_write
- compare only 4 bytes for IPv4 addresses in recent_entry_lookup

Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-24 14:53:12 +01:00
Alexey Dobriyan b0ceb560a4 netfilter: xt_recent: don't save proc dirs
Not needed, since creation and removal are done by name.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-11-20 09:57:01 +01:00
Harvey Harrison 14d5e834f6 net: replace NIPQUAD() in net/netfilter/
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u
can be replaced with %pI4

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-31 00:54:29 -07:00
Harvey Harrison 5b095d9892 net: replace %p6 with %pI6
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29 12:52:50 -07:00
Harvey Harrison 38ff4fa49b netfilter: replace uses of NIP6_FMT with %p6
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 16:08:13 -07:00
Alexey Dobriyan b09eec161b netfilter: xt_recent: use proc_create_data()
Fixes a crash in recent_seq_start:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000100
IP: [<ffffffffa002119c>] recent_seq_start+0x4c/0x90 [xt_recent]
PGD 17d33c067 PUD 107afe067 PMD 0
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
CPU 0
Modules linked in: ipt_LOG xt_recent af_packet iptable_nat nf_nat nf_conntrack_ipv4 nf_conntrack nf_defrag_ipv4 xt_tcpudp iptable_filter ip_tables x_tables ext2 nls_utf8 fuse sr_mod cdrom [last unloaded: ntfs]
Pid: 32373, comm: cat Not tainted 2.6.27-04ab591808565f968d4406f6435090ad671ebdab #6
RIP: 0010:[<ffffffffa002119c>]  [<ffffffffa002119c>] recent_seq_start+0x4c/0x90 [xt_recent]
RSP: 0018:ffff88015fed7e28  EFLAGS: 00010246
...

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-20 03:33:49 -07:00
Jan Engelhardt 6be3d8598e netfilter: xtables: move extension arguments into compound structure (3/6)
This patch does this for match extensions' destroy functions.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:19 +02:00
Jan Engelhardt 9b4fce7a35 netfilter: xtables: move extension arguments into compound structure (2/6)
This patch does this for match extensions' checkentry functions.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:18 +02:00
Jan Engelhardt f7108a20de netfilter: xtables: move extension arguments into compound structure (1/6)
The function signatures for Xtables extensions have grown over time.
It involves a lot of typing/replication, and also a bit of stack space
even if they are not used. Realize an NFWS2008 idea and pack them into
structs. The skb remains outside of the struct so gcc can continue to
apply its optimizations.

This patch does this for match extensions' match functions.

A few ambiguities have also been addressed. The "offset" parameter for
example has been renamed to "fragoff" (there are so many different
offsets already) and "protoff" to "thoff" (there is more than just one
protocol here, so clarify).

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:18 +02:00
Jan Engelhardt ee999d8b95 netfilter: x_tables: use NFPROTO_* in extensions
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:01 +02:00
Jan Engelhardt 079aa88fe7 netfilter: xt_recent: IPv6 support
This updates xt_recent to support the IPv6 address family.
The new /proc/net/xt_recent directory must be used for this.
The old proc interface can also be configured out.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:00 +02:00
Jan Engelhardt e948b20a71 netfilter: rename ipt_recent to xt_recent
Like with other modules (such as ipt_state), ipt_recent.h is changed
to forward definitions to (IOW include) xt_recent.h, and xt_recent.c
is changed to use the new constant names.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:00 +02:00