linux-toradex.git/net/ipv6, branch v6.0-rc7

ipv6: Fix crash when IPv6 is administratively disabled

2022-09-20T18:27:32+00:00

The global 'raw_v6_hashinfo' variable can be accessed even when IPv6 is
administratively disabled via the 'ipv6.disable=1' kernel command line
option, leading to a crash [1].

Fix by restoring the original behavior and always initializing the
variable, regardless of IPv6 support being administratively disabled or
not.

[1]
 BUG: unable to handle page fault for address: ffffffffffffffc8
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 173e18067 P4D 173e18067 PUD 173e1a067 PMD 0
 Oops: 0000 [#1] PREEMPT SMP KASAN
 CPU: 3 PID: 271 Comm: ss Not tainted 6.0.0-rc4-custom-00136-g0727a9a5fbc1 #1396
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
 RIP: 0010:raw_diag_dump+0x310/0x7f0
 [...]
 Call Trace:
  
  __inet_diag_dump+0x10f/0x2e0
  netlink_dump+0x575/0xfd0
  __netlink_dump_start+0x67b/0x940
  inet_diag_handler_cmd+0x273/0x2d0
  sock_diag_rcv_msg+0x317/0x440
  netlink_rcv_skb+0x15e/0x430
  sock_diag_rcv+0x2b/0x40
  netlink_unicast+0x53b/0x800
  netlink_sendmsg+0x945/0xe60
  ____sys_sendmsg+0x747/0x960
  ___sys_sendmsg+0x13a/0x1e0
  __sys_sendmsg+0x118/0x1e0
  do_syscall_64+0x34/0x80
  entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Fixes: 0daf07e52709 ("raw: convert raw sockets to RCU")
Reported-by: Roberto Ricci 
Tested-by: Roberto Ricci 
Signed-off-by: Ido Schimmel 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20220916084821.229287-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski

ipmr: Always call ip{,6}_mr_forward() from RCU read-side critical section

2022-09-20T15:22:15+00:00

These functions expect to be called from RCU read-side critical section,
but this only happens when invoked from the data path via
ip{,6}_mr_input(). They can also be invoked from process context in
response to user space adding a multicast route which resolves a cache
entry with queued packets [1][2].

Fix by adding missing rcu_read_lock() / rcu_read_unlock() in these call
paths.

[1]
WARNING: suspicious RCU usage
6.0.0-rc3-custom-15969-g049d233c8bcc-dirty #1387 Not tainted
-----------------------------
net/ipv4/ipmr.c:84 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by smcrouted/246:
 #0: ffffffff862389b0 (rtnl_mutex){+.+.}-{3:3}, at: ip_mroute_setsockopt+0x11c/0x1420

stack backtrace:
CPU: 0 PID: 246 Comm: smcrouted Not tainted 6.0.0-rc3-custom-15969-g049d233c8bcc-dirty #1387
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
Call Trace:
 
 dump_stack_lvl+0x91/0xb9
 vif_dev_read+0xbf/0xd0
 ipmr_queue_xmit+0x135/0x1ab0
 ip_mr_forward+0xe7b/0x13d0
 ipmr_mfc_add+0x1a06/0x2ad0
 ip_mroute_setsockopt+0x5c1/0x1420
 do_ip_setsockopt+0x23d/0x37f0
 ip_setsockopt+0x56/0x80
 raw_setsockopt+0x219/0x290
 __sys_setsockopt+0x236/0x4d0
 __x64_sys_setsockopt+0xbe/0x160
 do_syscall_64+0x34/0x80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

[2]
WARNING: suspicious RCU usage
6.0.0-rc3-custom-15969-g049d233c8bcc-dirty #1387 Not tainted
-----------------------------
net/ipv6/ip6mr.c:69 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by smcrouted/246:
 #0: ffffffff862389b0 (rtnl_mutex){+.+.}-{3:3}, at: ip6_mroute_setsockopt+0x6b9/0x2630

stack backtrace:
CPU: 1 PID: 246 Comm: smcrouted Not tainted 6.0.0-rc3-custom-15969-g049d233c8bcc-dirty #1387
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
Call Trace:
 
 dump_stack_lvl+0x91/0xb9
 vif_dev_read+0xbf/0xd0
 ip6mr_forward2.isra.0+0xc9/0x1160
 ip6_mr_forward+0xef0/0x13f0
 ip6mr_mfc_add+0x1ff2/0x31f0
 ip6_mroute_setsockopt+0x1825/0x2630
 do_ipv6_setsockopt+0x462/0x4440
 ipv6_setsockopt+0x105/0x140
 rawv6_setsockopt+0xd8/0x690
 __sys_setsockopt+0x236/0x4d0
 __x64_sys_setsockopt+0xbe/0x160
 do_syscall_64+0x34/0x80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: ebc3197963fc ("ipmr: add rcu protection over (struct vif_device)->dev")
Signed-off-by: Ido Schimmel 
Signed-off-by: Jakub Kicinski

ipv6: sr: fix out-of-bounds read when setting HMAC data.

2022-09-05T09:33:34+00:00

The SRv6 layer allows defining HMAC data that can later be used to sign IPv6
Segment Routing Headers. This configuration is realised via netlink through
four attributes: SEG6_ATTR_HMACKEYID, SEG6_ATTR_SECRET, SEG6_ATTR_SECRETLEN and
SEG6_ATTR_ALGID. Because the SECRETLEN attribute is decoupled from the actual
length of the SECRET attribute, it is possible to provide invalid combinations
(e.g., secret = "", secretlen = 64). This case is not checked in the code and
with an appropriately crafted netlink message, an out-of-bounds read of up
to 64 bytes (max secret length) can occur past the skb end pointer and into
skb_shared_info:

Breakpoint 1, seg6_genl_sethmac (skb=, info=) at net/ipv6/seg6.c:208
208		memcpy(hinfo->secret, secret, slen);
(gdb) bt
 #0  seg6_genl_sethmac (skb=, info=) at net/ipv6/seg6.c:208
 #1  0xffffffff81e012e9 in genl_family_rcv_msg_doit (skb=skb@entry=0xffff88800b1f9f00, nlh=nlh@entry=0xffff88800b1b7600,
    extack=extack@entry=0xffffc90000ba7af0, ops=ops@entry=0xffffc90000ba7a80, hdrlen=4, net=0xffffffff84237580 , family=,
    family=) at net/netlink/genetlink.c:731
 #2  0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00,
    family=0xffffffff82fef6c0 ) at net/netlink/genetlink.c:775
 #3  genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792
 #4  0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 )
    at net/netlink/af_netlink.c:2501
 #5  0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803
 #6  0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000)
    at net/netlink/af_netlink.c:1319
 #7  netlink_unicast (ssk=ssk@entry=0xffff888010eec800, skb=skb@entry=0xffff88800b1f9f00, portid=portid@entry=0, nonblock=)
    at net/netlink/af_netlink.c:1345
 #8  0xffffffff81dff9a4 in netlink_sendmsg (sock=, msg=0xffffc90000ba7e48, len=) at net/netlink/af_netlink.c:1921
...
(gdb) p/x ((struct sk_buff *)0xffff88800b1f9f00)->head + ((struct sk_buff *)0xffff88800b1f9f00)->end
$1 = 0xffff88800b1b76c0
(gdb) p/x secret
$2 = 0xffff88800b1b76c0
(gdb) p slen
$3 = 64 '@'

The OOB data can then be read back from userspace by dumping HMAC state. This
commit fixes this by ensuring SECRETLEN cannot exceed the actual length of
SECRET.

Reported-by: Lucas Leong 
Tested: verified that EINVAL is correctly returned when secretlen > len(secret)
Fixes: 4f4853dc1c9c1 ("ipv6: sr: implement API to control SR HMAC structure")
Signed-off-by: David Lebrun 
Signed-off-by: David S. Miller

bonding: add all node mcast address when slave up

2022-09-05T09:07:05+00:00

When a link is enslave to bond, it need to set the interface down first.
This makes the slave remove mac multicast address 33:33:00:00:00:01(The
IPv6 multicast address ff02::1 is kept even when the interface down). When
bond set the slave up, ipv6_mc_up() was not called due to commit c2edacf80e15
("bonding / ipv6: no addrconf for slaves separately from master").

This is not an issue before we adding the lladdr target feature for bonding,
as the mac multicast address will be added back when bond interface up and
join group ff02::1.

But after adding lladdr target feature for bonding. When user set a lladdr
target, the unsolicited NA message with all-nodes multicast dest will be
dropped as the slave interface never add 33:33:00:00:00:01 back.

Fix this by calling ipv6_mc_up() to add 33:33:00:00:00:01 back when
the slave interface up.

Reported-by: LiLiang 
Fixes: 5e1eeef69c0f ("bonding: NS target should accept link local address")
Signed-off-by: Hangbin Liu 
Signed-off-by: David S. Miller

rxrpc: Fix ICMP/ICMP6 error handling

2022-09-01T10:42:12+00:00

Because rxrpc pretends to be a tunnel on top of a UDP/UDP6 socket, allowing
it to siphon off UDP packets early in the handling of received UDP packets
thereby avoiding the packet going through the UDP receive queue, it doesn't
get ICMP packets through the UDP ->sk_error_report() callback.  In fact, it
doesn't appear that there's any usable option for getting hold of ICMP
packets.

Fix this by adding a new UDP encap hook to distribute error messages for
UDP tunnels.  If the hook is set, then the tunnel driver will be able to
see ICMP packets.  The hook provides the offset into the packet of the UDP
header of the original packet that caused the notification.

An alternative would be to call the ->error_handler() hook - but that
requires that the skbuff be cloned (as ip_icmp_error() or ipv6_cmp_error()
do, though isn't really necessary or desirable in rxrpc's case is we want
to parse them there and then, not queue them).

Changes
=======
ver #3)
 - Fixed an uninitialised variable.

ver #2)
 - Fixed some missing CONFIG_AF_RXRPC_IPV6 conditionals.

Fixes: 5271953cad31 ("rxrpc: Use the UDP encap_rcv hook")
Signed-off-by: David Howells

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf

2022-08-25T02:18:10+00:00

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

1) Fix crash with malformed ebtables blob which do not provide all
   entry points, from Florian Westphal.

2) Fix possible TCP connection clogging up with default 5-days
   timeout in conntrack, from Florian.

3) Fix crash in nf_tables tproxy with unsupported chains, also from Florian.

4) Do not allow to update implicit chains.

5) Make table handle allocation per-netns to fix data race.

6) Do not truncated payload length and offset, and checksum offset.
   Instead report EINVAl.

7) Enable chain stats update via static key iff no error occurs.

8) Restrict osf expression to ip, ip6 and inet families.

9) Restrict tunnel expression to netdev family.

10) Fix crash when trying to bind again an already bound chain.

11) Flowtable garbage collector might leave behind pending work to
    delete entries. This patch comes with a previous preparation patch
    as dependency.

12) Allow net.netfilter.nf_conntrack_frag6_high_thresh to be lowered,
    from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nf_defrag_ipv6: allow nf_conntrack_frag6_high_thresh increases
  netfilter: flowtable: fix stuck flows on cleanup due to pending work
  netfilter: flowtable: add function to invoke garbage collection immediately
  netfilter: nf_tables: disallow binding to already bound chain
  netfilter: nft_tunnel: restrict it to netdev family
  netfilter: nft_osf: restrict osf to ipv4, ipv6 and inet families
  netfilter: nf_tables: do not leave chain stats enabled on error
  netfilter: nft_payload: do not truncate csum_offset and csum_type
  netfilter: nft_payload: report ERANGE for too long offset and length
  netfilter: nf_tables: make table handle allocation per-netns friendly
  netfilter: nf_tables: disallow updates of implicit chain
  netfilter: nft_tproxy: restrict to prerouting hook
  netfilter: conntrack: work around exceeded receive window
  netfilter: ebtables: reject blobs that don't provide all entry points
====================

Link: https://lore.kernel.org/r/20220824220330.64283-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski

net: Fix data-races around sysctl_devconf_inherit_init_net.

2022-08-24T12:46:58+00:00

While reading sysctl_devconf_inherit_init_net, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: 856c395cfa63 ("net: introduce a knob to control whether to inherit devconf config")
Signed-off-by: Kuniyuki Iwashima 
Signed-off-by: David S. Miller

net: Fix data-races around sysctl_optmem_max.

2022-08-24T12:46:57+00:00

While reading sysctl_optmem_max, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima 
Signed-off-by: David S. Miller

netfilter: nf_defrag_ipv6: allow nf_conntrack_frag6_high_thresh increases

2022-08-24T06:06:44+00:00

Currently, net.netfilter.nf_conntrack_frag6_high_thresh can only be lowered.

I found this issue while investigating a probable kernel issue
causing flakes in tools/testing/selftests/net/ip_defrag.sh

In particular, these sysctl changes were ignored:
	ip netns exec "${NETNS}" sysctl -w net.netfilter.nf_conntrack_frag6_high_thresh=9000000 >/dev/null 2>&1
	ip netns exec "${NETNS}" sysctl -w net.netfilter.nf_conntrack_frag6_low_thresh=7000000  >/dev/null 2>&1

This change is inline with commit 836196239298 ("net/ipfrag: let ip[6]frag_high_thresh
in ns be higher than in init_net")

Fixes: 8db3d41569bb ("netfilter: nf_defrag_ipv6: use net_generic infra")
Signed-off-by: Eric Dumazet 
Signed-off-by: Pablo Neira Ayuso

net: fix potential refcount leak in ndisc_router_discovery()

2022-08-15T10:40:28+00:00

The issue happens on specific paths in the function. After both the
object `rt` and `neigh` are grabbed successfully, when `lifetime` is
nonzero but the metric needs change, the function just deletes the
route and set `rt` to NULL. Then, it may try grabbing `rt` and `neigh`
again if above conditions hold. The function simply overwrite `neigh`
if succeeds or returns if fails, without decreasing the reference
count of previous `neigh`. This may result in memory leaks.

Fix it by decrementing the reference count of `neigh` in place.

Fixes: 6b2e04bc240f ("net: allow user to set metric on default route learned via Router Advertisement")
Signed-off-by: Xin Xiong 
Signed-off-by: Xin Tan 
Signed-off-by: David S. Miller