linux-stable.git/net/core/rtnetlink.c, branch v4.20.2

rtnetlink: ndo_dflt_fdb_dump() only work for ARPHRD_ETHER devices

2018-12-05T04:28:22+00:00

kmsan was able to trigger a kernel-infoleak using a gre device [1]

nlmsg_populate_fdb_fill() has a hard coded assumption
that dev->addr_len is ETH_ALEN, as normally guaranteed
for ARPHRD_ETHER devices.

A similar issue was fixed recently in commit da71577545a5
("rtnetlink: Disallow FDB configuration for non-Ethernet device")

[1]
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:143 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x4c0/0x2700 lib/iov_iter.c:576
CPU: 0 PID: 6697 Comm: syz-executor310 Not tainted 4.20.0-rc3+ #95
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+0x32d/0x480 lib/dump_stack.c:113
 kmsan_report+0x12c/0x290 mm/kmsan/kmsan.c:683
 kmsan_internal_check_memory+0x32a/0xa50 mm/kmsan/kmsan.c:743
 kmsan_copy_to_user+0x78/0xd0 mm/kmsan/kmsan_hooks.c:634
 copyout lib/iov_iter.c:143 [inline]
 _copy_to_iter+0x4c0/0x2700 lib/iov_iter.c:576
 copy_to_iter include/linux/uio.h:143 [inline]
 skb_copy_datagram_iter+0x4e2/0x1070 net/core/datagram.c:431
 skb_copy_datagram_msg include/linux/skbuff.h:3316 [inline]
 netlink_recvmsg+0x6f9/0x19d0 net/netlink/af_netlink.c:1975
 sock_recvmsg_nosec net/socket.c:794 [inline]
 sock_recvmsg+0x1d1/0x230 net/socket.c:801
 ___sys_recvmsg+0x444/0xae0 net/socket.c:2278
 __sys_recvmsg net/socket.c:2327 [inline]
 __do_sys_recvmsg net/socket.c:2337 [inline]
 __se_sys_recvmsg+0x2fa/0x450 net/socket.c:2334
 __x64_sys_recvmsg+0x4a/0x70 net/socket.c:2334
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x441119
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffc7f008a8 EFLAGS: 00000207 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000441119
RDX: 0000000000000040 RSI: 00000000200005c0 RDI: 0000000000000003
RBP: 00000000006cc018 R08: 0000000000000100 R09: 0000000000000100
R10: 0000000000000100 R11: 0000000000000207 R12: 0000000000402080
R13: 0000000000402110 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:246 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:261 [inline]
 kmsan_internal_chain_origin+0x13d/0x240 mm/kmsan/kmsan.c:469
 kmsan_memcpy_memmove_metadata+0x1a9/0xf70 mm/kmsan/kmsan.c:344
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:362
 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:162
 __nla_put lib/nlattr.c:744 [inline]
 nla_put+0x20a/0x2d0 lib/nlattr.c:802
 nlmsg_populate_fdb_fill+0x444/0x810 net/core/rtnetlink.c:3466
 nlmsg_populate_fdb net/core/rtnetlink.c:3775 [inline]
 ndo_dflt_fdb_dump+0x73a/0x960 net/core/rtnetlink.c:3807
 rtnl_fdb_dump+0x1318/0x1cb0 net/core/rtnetlink.c:3979
 netlink_dump+0xc79/0x1c90 net/netlink/af_netlink.c:2244
 __netlink_dump_start+0x10c4/0x11d0 net/netlink/af_netlink.c:2352
 netlink_dump_start include/linux/netlink.h:216 [inline]
 rtnetlink_rcv_msg+0x141b/0x1540 net/core/rtnetlink.c:4910
 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4965
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1699/0x1740 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x13c7/0x1440 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe3b/0x1240 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:246 [inline]
 kmsan_internal_poison_shadow+0x6d/0x130 mm/kmsan/kmsan.c:170
 kmsan_kmalloc+0xa1/0x100 mm/kmsan/kmsan_hooks.c:186
 __kmalloc+0x14c/0x4d0 mm/slub.c:3825
 kmalloc include/linux/slab.h:551 [inline]
 __hw_addr_create_ex net/core/dev_addr_lists.c:34 [inline]
 __hw_addr_add_ex net/core/dev_addr_lists.c:80 [inline]
 __dev_mc_add+0x357/0x8a0 net/core/dev_addr_lists.c:670
 dev_mc_add+0x6d/0x80 net/core/dev_addr_lists.c:687
 ip_mc_filter_add net/ipv4/igmp.c:1128 [inline]
 igmp_group_added+0x4d4/0xb80 net/ipv4/igmp.c:1311
 __ip_mc_inc_group+0xea9/0xf70 net/ipv4/igmp.c:1444
 ip_mc_inc_group net/ipv4/igmp.c:1453 [inline]
 ip_mc_up+0x1c3/0x400 net/ipv4/igmp.c:1775
 inetdev_event+0x1d03/0x1d80 net/ipv4/devinet.c:1522
 notifier_call_chain kernel/notifier.c:93 [inline]
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x13d/0x240 kernel/notifier.c:401
 __dev_notify_flags+0x3da/0x860 net/core/dev.c:1733
 dev_change_flags+0x1ac/0x230 net/core/dev.c:7569
 do_setlink+0x165f/0x5ea0 net/core/rtnetlink.c:2492
 rtnl_newlink+0x2ad7/0x35a0 net/core/rtnetlink.c:3111
 rtnetlink_rcv_msg+0x1148/0x1540 net/core/rtnetlink.c:4947
 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4965
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1699/0x1740 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x13c7/0x1440 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe3b/0x1240 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 36-37 of 105 are uninitialized
Memory access of size 105 starts at ffff88819686c000
Data copied to user address 0000000020000380

Fixes: d83b06036048 ("net: add fdb generic dump routine")
Signed-off-by: Eric Dumazet 
Cc: John Fastabend 
Cc: Ido Schimmel 
Cc: David Ahern 
Reviewed-by: Ido Schimmel 
Signed-off-by: David S. Miller

rtnetlink: restore handling of dumpit return value in rtnl_dump_all()

2018-11-06T01:04:54+00:00

For non-zero return from dumpit() we should break the loop
in rtnl_dump_all() and return the result. Otherwise, e.g.,
we could get the memory leak in inet6_dump_fib() [1]. The
pointer to the allocated struct fib6_walker there (saved
in cb->args) can be lost, reset on the next iteration.

Fix it by partially restoring the previous behavior before
commit c63586dc9b3e ("net: rtnl_dump_all needs to propagate
error from dumpit function"). The returned error from
dumpit() is still passed further.

[1]:
unreferenced object 0xffff88001322a200 (size 96):
  comm "sshd", pid 1484, jiffies 4296032768 (age 1432.542s)
  hex dump (first 32 bytes):
    00 01 00 00 00 00 ad de 00 02 00 00 00 00 ad de  ................
    18 09 41 36 00 88 ff ff 18 09 41 36 00 88 ff ff  ..A6......A6....
  backtrace:
    [<0000000095846b39>] kmem_cache_alloc_trace+0x151/0x220
    [<000000007d12709f>] inet6_dump_fib+0x68d/0x940
    [<000000002775a316>] rtnl_dump_all+0x1d9/0x2d0
    [<00000000d7cd302b>] netlink_dump+0x945/0x11a0
    [<000000002f43485f>] __netlink_dump_start+0x55d/0x800
    [<00000000f76bbeec>] rtnetlink_rcv_msg+0x4fa/0xa00
    [<000000009b5761f3>] netlink_rcv_skb+0x29c/0x420
    [<0000000087a1dae1>] rtnetlink_rcv+0x15/0x20
    [<00000000691b703b>] netlink_unicast+0x4e3/0x6c0
    [<00000000b5be0204>] netlink_sendmsg+0x7f2/0xba0
    [<0000000096d2aa60>] sock_sendmsg+0xba/0xf0
    [<000000008c1b786f>] __sys_sendto+0x1e4/0x330
    [<0000000019587b3f>] __x64_sys_sendto+0xe1/0x1a0
    [<00000000071f4d56>] do_syscall_64+0x9f/0x300
    [<000000002737577f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [<0000000057587684>] 0xffffffffffffffff

Fixes: c63586dc9b3e ("net: rtnl_dump_all needs to propagate error from dumpit function")
Signed-off-by: Alexey Kodanev 
Signed-off-by: David S. Miller

rtnetlink: Disallow FDB configuration for non-Ethernet device

2018-10-30T03:52:35+00:00

When an FDB entry is configured, the address is validated to have the
length of an Ethernet address, but the device for which the address is
configured can be of any type.

The above can result in the use of uninitialized memory when the address
is later compared against existing addresses since 'dev->addr_len' is
used and it may be greater than ETH_ALEN, as with ip6tnl devices.

Fix this by making sure that FDB entries are only configured for
Ethernet devices.

BUG: KMSAN: uninit-value in memcmp+0x11d/0x180 lib/string.c:863
CPU: 1 PID: 4318 Comm: syz-executor998 Not tainted 4.19.0-rc3+ #49
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+0x14b/0x190 lib/dump_stack.c:113
  kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:956
  __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
  memcmp+0x11d/0x180 lib/string.c:863
  dev_uc_add_excl+0x165/0x7b0 net/core/dev_addr_lists.c:464
  ndo_dflt_fdb_add net/core/rtnetlink.c:3463 [inline]
  rtnl_fdb_add+0x1081/0x1270 net/core/rtnetlink.c:3558
  rtnetlink_rcv_msg+0xa0b/0x1530 net/core/rtnetlink.c:4715
  netlink_rcv_skb+0x36e/0x5f0 net/netlink/af_netlink.c:2454
  rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4733
  netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
  netlink_unicast+0x1638/0x1720 net/netlink/af_netlink.c:1343
  netlink_sendmsg+0x1205/0x1290 net/netlink/af_netlink.c:1908
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg net/socket.c:631 [inline]
  ___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
  __sys_sendmsg net/socket.c:2152 [inline]
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
  __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
  do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
  entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x440ee9
Code: e8 cc ab 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 bb 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff6a93b518 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440ee9
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000213 R12: 000000000000b4b0
R13: 0000000000401ec0 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
  kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
  kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
  kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
  kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100
  slab_post_alloc_hook mm/slab.h:446 [inline]
  slab_alloc_node mm/slub.c:2718 [inline]
  __kmalloc_node_track_caller+0x9e7/0x1160 mm/slub.c:4351
  __kmalloc_reserve net/core/skbuff.c:138 [inline]
  __alloc_skb+0x2f5/0x9e0 net/core/skbuff.c:206
  alloc_skb include/linux/skbuff.h:996 [inline]
  netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline]
  netlink_sendmsg+0xb49/0x1290 net/netlink/af_netlink.c:1883
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg net/socket.c:631 [inline]
  ___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
  __sys_sendmsg net/socket.c:2152 [inline]
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
  __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
  do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
  entry_SYSCALL_64_after_hwframe+0x63/0xe7

v2:
* Make error message more specific (David)

Fixes: 090096bf3db1 ("net: generic fdb support for drivers without ndo_fdb_")
Signed-off-by: Ido Schimmel 
Reported-and-tested-by: syzbot+3a288d5f5530b901310e@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+d53ab4e92a1db04110ff@syzkaller.appspotmail.com
Cc: Vlad Yasevich 
Cc: David Ahern 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller

net: rtnl_dump_all needs to propagate error from dumpit function

2018-10-24T21:06:25+00:00

If an address, route or netconf dump request is sent for AF_UNSPEC, then
rtnl_dump_all is used to do the dump across all address families. If one
of the dumpit functions fails (e.g., invalid attributes in the dump
request) then rtnl_dump_all needs to propagate that error so the user
gets an appropriate response instead of just getting no data.

Fixes: effe67926624 ("net: Enable kernel side filtering of route dumps")
Fixes: 5fcd266a9f64 ("net/ipv4: Add support for dumping addresses for a specific device")
Fixes: 6371a71f3a3b ("net/ipv6: Add support for dumping addresses for a specific device")
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net: bridge: add support for per-port vlan stats

2018-10-12T17:18:58+00:00

This patch adds an option to have per-port vlan stats instead of the
default global stats. The option can be set only when there are no port
vlans in the bridge since we need to allocate the stats if it is set
when vlans are being added to ports (and respectively free them
when being deleted). Also bump RTNL_MAX_TYPE as the bridge is the
largest user of options. The current stats design allows us to add
these without any changes to the fast-path, it all comes down to
the per-vlan stats pointer which, if this option is enabled, will
be allocated for each port vlan instead of using the global bridge-wide
one.

CC: bridge@lists.linux-foundation.org
CC: Roopa Prabhu 
Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

rtnetlink: Update comment in rtnl_stats_dump regarding strict data checking

2018-10-11T05:24:51+00:00

The NLM_F_DUMP_PROPER_HDR netlink flag was replaced by a setsockopt.
Update the comment in rtnl_stats_dump.

Fixes: 841891ec0c65 ("rtnetlink: Update rtnl_stats_dump for strict data checking")
Reported-by: Christian Brauner 
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

rtnetlink: Move ifm in valid_fdb_dump_legacy to closer to use

2018-10-11T05:24:33+00:00

Move setting of local variable ifm to after the message parsing in
valid_fdb_dump_legacy. Avoid potential future use of unchecked variable.

Fixes: 8dfbda19a21b ("rtnetlink: Move input checking for rtnl_fdb_dump to helper")
Reported-by: Christian Brauner 
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

rtnetlink: Update rtnl_fdb_dump for strict data checking

2018-10-08T17:39:05+00:00

Update rtnl_fdb_dump for strict data checking. If the flag is set,
the dump request is expected to have an ndmsg struct as the header
potentially followed by one or more attributes. Any data passed in the
header or as an attribute is taken as a request to influence the data
returned. Only values supported by the dump handler are allowed to be
non-0 or set in the request. At the moment only the NDA_IFINDEX and
NDA_MASTER attributes are supported.

Signed-off-by: David Ahern 
Acked-by: Christian Brauner 
Signed-off-by: David S. Miller

rtnetlink: Move input checking for rtnl_fdb_dump to helper

2018-10-08T17:39:05+00:00

Move the existing input checking for rtnl_fdb_dump into a helper,
valid_fdb_dump_legacy. This function will retain the current
logic that works around the 2 headers that userspace has been
allowed to send up to this point.

Signed-off-by: David Ahern 
Acked-by: Christian Brauner 
Signed-off-by: David S. Miller

rtnetlink: Update rtnl_stats_dump for strict data checking

2018-10-08T17:39:04+00:00

Update rtnl_stats_dump for strict data checking. If the flag is set,
the dump request is expected to have an if_stats_msg struct as the header.
All elements of the struct are expected to be 0 except filter_mask which
must be non-0 (legacy behavior). No attributes are supported.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller