linux-toradex.git/include/linux/igmp.h, branch v6.0-rc1

net/ipv4/igmp: Use struct_size() helper

2021-08-05T10:46:42+00:00

Replace IP_SFLSIZE() with struct_size() helper in order to avoid any
potential type mistakes or integer overflows that, in the worst
scenario, could lead to heap overflows.

Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: David S. Miller

ip*_mc_gsfget(): lift copyout of struct group_filter into callers

2020-05-21T00:31:27+00:00

pass the userland pointer to the array in its tail, so that part
gets copied out by our functions; copyout of everything else is
done in the callers.  Rationale: reuse for compat; the array
is the same in native and compat, the layout of parts before it
is different for compat.

Signed-off-by: Al Viro

igmp.h: Replace zero-length array with flexible-array member

2020-04-18T20:44:55+00:00

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2019-06-07T18:00:14+00:00

Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.

Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman

ipv4/igmp: shrink struct ip_sf_list

2019-05-23T00:57:37+00:00

Removing two 4 bytes holes allows to use kmalloc-32
kmem cache instead of kmalloc-64 on 64bit kernels.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

ip: fix ip_mc_may_pull() return value

2019-03-10T03:52:47+00:00

ip_mc_may_pull() must return 0 if there is a problem, not an errno.

syzbot reported :

BUG: KASAN: use-after-free in br_ip4_multicast_igmp3_report net/bridge/br_multicast.c:947 [inline]
BUG: KASAN: use-after-free in br_multicast_ipv4_rcv net/bridge/br_multicast.c:1631 [inline]
BUG: KASAN: use-after-free in br_multicast_rcv+0x3cd8/0x4440 net/bridge/br_multicast.c:1741
Read of size 4 at addr ffff88820a4084ee by task syz-executor.2/11183

CPU: 1 PID: 11183 Comm: syz-executor.2 Not tainted 5.0.0+ #14
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 br_ip4_multicast_igmp3_report net/bridge/br_multicast.c:947 [inline]
 br_multicast_ipv4_rcv net/bridge/br_multicast.c:1631 [inline]
 br_multicast_rcv+0x3cd8/0x4440 net/bridge/br_multicast.c:1741
 br_handle_frame_finish+0xa3a/0x14c0 net/bridge/br_input.c:108
 br_nf_hook_thresh+0x2ec/0x380 net/bridge/br_netfilter_hooks.c:1005
 br_nf_pre_routing_finish+0x8e2/0x1750 net/bridge/br_netfilter_hooks.c:410
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 br_nf_pre_routing+0x7e7/0x13a0 net/bridge/br_netfilter_hooks.c:506
 nf_hook_entry_hookfn include/linux/netfilter.h:119 [inline]
 nf_hook_slow+0xbf/0x1f0 net/netfilter/core.c:511
 nf_hook include/linux/netfilter.h:244 [inline]
 NF_HOOK include/linux/netfilter.h:287 [inline]
 br_handle_frame+0x95b/0x1450 net/bridge/br_input.c:305
 __netif_receive_skb_core+0xa96/0x3040 net/core/dev.c:4902
 __netif_receive_skb_one_core+0xa8/0x1a0 net/core/dev.c:4971
 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083
 netif_receive_skb_internal+0x117/0x660 net/core/dev.c:5186
 netif_receive_skb+0x6e/0x5a0 net/core/dev.c:5261

Fixes: ba5ea614622d ("bridge: simplify ip_mc_check_igmp() and ipv6_mc_check_mld() calls")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Cc: Linus Lüssing 
Signed-off-by: David S. Miller

net: Fix ip_mc_{dec,inc}_group allocation context

2019-02-03T20:11:12+00:00

After 4effd28c1245 ("bridge: join all-snoopers multicast address"), I
started seeing the following sleep in atomic warnings:

[   26.763893] BUG: sleeping function called from invalid context at mm/slab.h:421
[   26.771425] in_atomic(): 1, irqs_disabled(): 0, pid: 1658, name: sh
[   26.777855] INFO: lockdep is turned off.
[   26.781916] CPU: 0 PID: 1658 Comm: sh Not tainted 5.0.0-rc4 #20
[   26.787943] Hardware name: BCM97278SV (DT)
[   26.792118] Call trace:
[   26.794645]  dump_backtrace+0x0/0x170
[   26.798391]  show_stack+0x24/0x30
[   26.801787]  dump_stack+0xa4/0xe4
[   26.805182]  ___might_sleep+0x208/0x218
[   26.809102]  __might_sleep+0x78/0x88
[   26.812762]  kmem_cache_alloc_trace+0x64/0x28c
[   26.817301]  igmp_group_dropped+0x150/0x230
[   26.821573]  ip_mc_dec_group+0x1b0/0x1f8
[   26.825585]  br_ip4_multicast_leave_snoopers.isra.11+0x174/0x190
[   26.831704]  br_multicast_toggle+0x78/0xcc
[   26.835887]  store_bridge_parm+0xc4/0xfc
[   26.839894]  multicast_snooping_store+0x3c/0x4c
[   26.844517]  dev_attr_store+0x44/0x5c
[   26.848262]  sysfs_kf_write+0x50/0x68
[   26.852006]  kernfs_fop_write+0x14c/0x1b4
[   26.856102]  __vfs_write+0x60/0x190
[   26.859668]  vfs_write+0xc8/0x168
[   26.863059]  ksys_write+0x70/0xc8
[   26.866449]  __arm64_sys_write+0x24/0x30
[   26.870458]  el0_svc_common+0xa0/0x11c
[   26.874291]  el0_svc_handler+0x38/0x70
[   26.878120]  el0_svc+0x8/0xc

while toggling the bridge's multicast_snooping attribute dynamically.

Pass a gfp_t down to igmpv3_add_delrec(), introduce
__igmp_group_dropped() and introduce __ip_mc_dec_group() to take a gfp_t
argument.

Similarly introduce ____ip_mc_inc_group() and __ip_mc_inc_group() to
allow caller to specify gfp_t.

IPv6 part of the patch appears fine.

Fixes: 4effd28c1245 ("bridge: join all-snoopers multicast address")
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller

bridge: simplify ip_mc_check_igmp() and ipv6_mc_check_mld() calls

2019-01-23T01:18:08+00:00

This patch refactors ip_mc_check_igmp(), ipv6_mc_check_mld() and
their callers (more precisely, the Linux bridge) to not rely on
the skb_trimmed parameter anymore.

An skb with its tail trimmed to the IP packet length was initially
introduced for the following three reasons:

1) To be able to verify the ICMPv6 checksum.
2) To be able to distinguish the version of an IGMP or MLD query.
   They are distinguishable only by their size.
3) To avoid parsing data for an IGMPv3 or MLDv2 report that is
   beyond the IP packet but still within the skb.

The first case still uses a cloned and potentially trimmed skb to
verfiy. However, there is no need to propagate it to the caller.
For the second and third case explicit IP packet length checks were
added.

This hopefully makes ip_mc_check_igmp() and ipv6_mc_check_mld() easier
to read and verfiy, as well as easier to use.

Signed-off-by: Linus Lüssing 
Signed-off-by: David S. Miller

ipv4/igmp: init group mode as INCLUDE when join source group

2018-07-16T18:20:06+00:00

Based on RFC3376 5.1
   If no interface
   state existed for that multicast address before the change (i.e., the
   change consisted of creating a new per-interface record), or if no
   state exists after the change (i.e., the change consisted of deleting
   a per-interface record), then the "non-existent" state is considered
   to have a filter mode of INCLUDE and an empty source list.

Which means a new multicast group should start with state IN().

Function ip_mc_join_group() works correctly for IGMP ASM(Any-Source Multicast)
mode. It adds a group with state EX() and inits crcount to mc_qrv,
so the kernel will send a TO_EX() report message after adding group.

But for IGMPv3 SSM(Source-specific multicast) JOIN_SOURCE_GROUP mode, we
split the group joining into two steps. First we join the group like ASM,
i.e. via ip_mc_join_group(). So the state changes from IN() to EX().

Then we add the source-specific address with INCLUDE mode. So the state
changes from EX() to IN(A).

Before the first step sends a group change record, we finished the second
step. So we will only send the second change record. i.e. TO_IN(A).

Regarding the RFC stands, we should actually send an ALLOW(A) message for
SSM JOIN_SOURCE_GROUP as the state should mimic the 'IN() to IN(A)'
transition.

The issue was exposed by commit a052517a8ff65 ("net/multicast: should not
send source list records when have filter mode change"). Before this change,
we used to send both ALLOW(A) and TO_IN(A). After this change we only send
TO_IN(A).

Fix it by adding a new parameter to init group mode. Also add new wrapper
functions so we don't need to change too much code.

v1 -> v2:
In my first version I only cleared the group change record. But this is not
enough. Because when a new group join, it will init as EXCLUDE and trigger
an filter mode change in ip/ip6_mc_add_src(), which will clear all source
addresses' sf_crcount. This will prevent early joined address sending state
change records if multi source addressed joined at the same time.

In v2 patch, I fixed it by directly initializing the mode to INCLUDE for SSM
JOIN_SOURCE_GROUP. I also split the original patch into two separated patches
for IPv4 and IPv6.

Fixes: a052517a8ff65 ("net/multicast: should not send source list records when have filter mode change")
Reviewed-by: Stefano Brivio 
Signed-off-by: Hangbin Liu 
Signed-off-by: David S. Miller