Commit Graph

553 Commits

Author SHA1 Message Date
Eric Dumazet
239e827e36 netlink: do not reset transport header in netlink_recvmsg()
[ Upstream commit d5076fe4049cadef1f040eda4aaa001bb5424225 ]

netlink_recvmsg() does not need to change transport header.

If transport header was needed, it should have been reset
by the producer (netlink_dump()), not the consumer(s).

The following trace probably happened when multiple threads
were using MSG_PEEK.

BUG: KCSAN: data-race in netlink_recvmsg / netlink_recvmsg

write to 0xffff88811e9f15b2 of 2 bytes by task 32012 on cpu 1:
 skb_reset_transport_header include/linux/skbuff.h:2760 [inline]
 netlink_recvmsg+0x1de/0x790 net/netlink/af_netlink.c:1978
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 __sys_recvfrom+0x204/0x2c0 net/socket.c:2097
 __do_sys_recvfrom net/socket.c:2115 [inline]
 __se_sys_recvfrom net/socket.c:2111 [inline]
 __x64_sys_recvfrom+0x74/0x90 net/socket.c:2111
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

write to 0xffff88811e9f15b2 of 2 bytes by task 32005 on cpu 0:
 skb_reset_transport_header include/linux/skbuff.h:2760 [inline]
 netlink_recvmsg+0x1de/0x790 net/netlink/af_netlink.c:1978
 ____sys_recvmsg+0x162/0x2f0
 ___sys_recvmsg net/socket.c:2674 [inline]
 __sys_recvmsg+0x209/0x3f0 net/socket.c:2704
 __do_sys_recvmsg net/socket.c:2714 [inline]
 __se_sys_recvmsg net/socket.c:2711 [inline]
 __x64_sys_recvmsg+0x42/0x50 net/socket.c:2711
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff -> 0x0000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 32005 Comm: syz-executor.4 Not tainted 5.18.0-rc1-syzkaller-00328-ge1f700ebd6be-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220505161946.2867638-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 09:42:47 +02:00
Eric Dumazet
c99c91fa17 netlink: reset network and mac headers in netlink_dump()
[ Upstream commit 99c07327ae11e24886d552dddbe4537bfca2765d ]

netlink_dump() is allocating an skb, reserves space in it
but forgets to reset network header.

This allows a BPF program, invoked later from sk_filter()
to access uninitialized kernel memory from the reserved
space.

Theorically mac header reset could be omitted, because
it is set to a special initial value.
bpf_internal_load_pointer_neg_helper calls skb_mac_header()
without checking skb_mac_header_was_set().
Relying on skb->len not being too big seems fragile.
We also could add a sanity check in bpf_internal_load_pointer_neg_helper()
to avoid surprises in the future.

syzbot report was:

BUG: KMSAN: uninit-value in ___bpf_prog_run+0xa22b/0xb420 kernel/bpf/core.c:1637
 ___bpf_prog_run+0xa22b/0xb420 kernel/bpf/core.c:1637
 __bpf_prog_run32+0x121/0x180 kernel/bpf/core.c:1796
 bpf_dispatcher_nop_func include/linux/bpf.h:784 [inline]
 __bpf_prog_run include/linux/filter.h:626 [inline]
 bpf_prog_run include/linux/filter.h:633 [inline]
 __bpf_prog_run_save_cb+0x168/0x580 include/linux/filter.h:756
 bpf_prog_run_save_cb include/linux/filter.h:770 [inline]
 sk_filter_trim_cap+0x3bc/0x8c0 net/core/filter.c:150
 sk_filter include/linux/filter.h:905 [inline]
 netlink_dump+0xe0c/0x16c0 net/netlink/af_netlink.c:2276
 netlink_recvmsg+0x1129/0x1c80 net/netlink/af_netlink.c:2002
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 sock_read_iter+0x5a9/0x630 net/socket.c:1039
 do_iter_readv_writev+0xa7f/0xc70
 do_iter_read+0x52c/0x14c0 fs/read_write.c:786
 vfs_readv fs/read_write.c:906 [inline]
 do_readv+0x432/0x800 fs/read_write.c:943
 __do_sys_readv fs/read_write.c:1034 [inline]
 __se_sys_readv fs/read_write.c:1031 [inline]
 __x64_sys_readv+0xe5/0x120 fs/read_write.c:1031
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was stored to memory at:
 ___bpf_prog_run+0x96c/0xb420 kernel/bpf/core.c:1558
 __bpf_prog_run32+0x121/0x180 kernel/bpf/core.c:1796
 bpf_dispatcher_nop_func include/linux/bpf.h:784 [inline]
 __bpf_prog_run include/linux/filter.h:626 [inline]
 bpf_prog_run include/linux/filter.h:633 [inline]
 __bpf_prog_run_save_cb+0x168/0x580 include/linux/filter.h:756
 bpf_prog_run_save_cb include/linux/filter.h:770 [inline]
 sk_filter_trim_cap+0x3bc/0x8c0 net/core/filter.c:150
 sk_filter include/linux/filter.h:905 [inline]
 netlink_dump+0xe0c/0x16c0 net/netlink/af_netlink.c:2276
 netlink_recvmsg+0x1129/0x1c80 net/netlink/af_netlink.c:2002
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 sock_read_iter+0x5a9/0x630 net/socket.c:1039
 do_iter_readv_writev+0xa7f/0xc70
 do_iter_read+0x52c/0x14c0 fs/read_write.c:786
 vfs_readv fs/read_write.c:906 [inline]
 do_readv+0x432/0x800 fs/read_write.c:943
 __do_sys_readv fs/read_write.c:1034 [inline]
 __se_sys_readv fs/read_write.c:1031 [inline]
 __x64_sys_readv+0xe5/0x120 fs/read_write.c:1031
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:737 [inline]
 slab_alloc_node mm/slub.c:3244 [inline]
 __kmalloc_node_track_caller+0xde3/0x14f0 mm/slub.c:4972
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0x545/0xf90 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1158 [inline]
 netlink_dump+0x30f/0x16c0 net/netlink/af_netlink.c:2242
 netlink_recvmsg+0x1129/0x1c80 net/netlink/af_netlink.c:2002
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 sock_read_iter+0x5a9/0x630 net/socket.c:1039
 do_iter_readv_writev+0xa7f/0xc70
 do_iter_read+0x52c/0x14c0 fs/read_write.c:786
 vfs_readv fs/read_write.c:906 [inline]
 do_readv+0x432/0x800 fs/read_write.c:943
 __do_sys_readv fs/read_write.c:1034 [inline]
 __se_sys_readv fs/read_write.c:1031 [inline]
 __x64_sys_readv+0xe5/0x120 fs/read_write.c:1031
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CPU: 0 PID: 3470 Comm: syz-executor751 Not tainted 5.17.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: db65a3aaf2 ("netlink: Trim skb to alloc size to avoid MSG_TRUNC")
Fixes: 9063e21fb0 ("netlink: autosize skb lengthes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220415181442.551228-1-eric.dumazet@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-27 13:39:43 +02:00
Petr Machata
f75f4abeec af_netlink: Fix shift out of bounds in group mask calculation
[ Upstream commit 0caf6d9922192dd1afa8dc2131abfb4df1443b9f ]

When a netlink message is received, netlink_recvmsg() fills in the address
of the sender. One of the fields is the 32-bit bitfield nl_groups, which
carries the multicast group on which the message was received. The least
significant bit corresponds to group 1, and therefore the highest group
that the field can represent is 32. Above that, the UB sanitizer flags the
out-of-bounds shift attempts.

Which bits end up being set in such case is implementation defined, but
it's either going to be a wrong non-zero value, or zero, which is at least
not misleading. Make the latter choice deterministic by always setting to 0
for higher-numbered multicast groups.

To get information about membership in groups >= 32, userspace is expected
to use nl_pktinfo control messages[0], which are enabled by NETLINK_PKTINFO
socket option.
[0] https://lwn.net/Articles/147608/

The way to trigger this issue is e.g. through monitoring the BRVLAN group:

	# bridge monitor vlan &
	# ip link add name br type bridge

Which produces the following citation:

	UBSAN: shift-out-of-bounds in net/netlink/af_netlink.c:162:19
	shift exponent 32 is too large for 32-bit type 'int'

Fixes: f7fa9b10ed ("[NETLINK]: Support dynamic number of multicast groups per netlink family")
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/2bef6aabf201d1fc16cca139a744700cff9dcb04.1647527635.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-15 14:14:50 +02:00
Harshit Mogalapalli
ff3f517bf7 net: netlink: af_netlink: Prevent empty skb by adding a check on len.
[ Upstream commit f123cffdd8fe8ea6c7fded4b88516a42798797d0 ]

Adding a check on len parameter to avoid empty skb. This prevents a
division error in netem_enqueue function which is caused when skb->len=0
and skb->data_len=0 in the randomized corruption step as shown below.

skb->data[prandom_u32() % skb_headlen(skb)] ^= 1<<(prandom_u32() % 8);

Crash Report:
[  343.170349] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family
0 port 6081 - 0
[  343.216110] netem: version 1.3
[  343.235841] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
[  343.236680] CPU: 3 PID: 4288 Comm: reproducer Not tainted 5.16.0-rc1+
[  343.237569] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.11.0-2.el7 04/01/2014
[  343.238707] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem]
[  343.239499] Code: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff
ff 8b 8d 50 ff ff ff 8b 85 58 ff ff ff 48 8b bd 70 ff ff ff 31 d2 2b 4f
74 <f7> f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03
[  343.241883] RSP: 0018:ffff88800bcd7368 EFLAGS: 00010246
[  343.242589] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX:
0000000000000000
[  343.243542] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI:
ffff88800f8eda40
[  343.244474] RBP: ffff88800bcd7458 R08: 0000000000000000 R09:
ffffffff94fb8445
[  343.245403] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12:
0000000000000000
[  343.246355] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15:
0000000000000020
[  343.247291] FS:  00007fdde2bd7700(0000) GS:ffff888109780000(0000)
knlGS:0000000000000000
[  343.248350] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  343.249120] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4:
00000000000006e0
[  343.250076] Call Trace:
[  343.250423]  <TASK>
[  343.250713]  ? memcpy+0x4d/0x60
[  343.251162]  ? netem_init+0xa0/0xa0 [sch_netem]
[  343.251795]  ? __sanitizer_cov_trace_pc+0x21/0x60
[  343.252443]  netem_enqueue+0xe28/0x33c0 [sch_netem]
[  343.253102]  ? stack_trace_save+0x87/0xb0
[  343.253655]  ? filter_irq_stacks+0xb0/0xb0
[  343.254220]  ? netem_init+0xa0/0xa0 [sch_netem]
[  343.254837]  ? __kasan_check_write+0x14/0x20
[  343.255418]  ? _raw_spin_lock+0x88/0xd6
[  343.255953]  dev_qdisc_enqueue+0x50/0x180
[  343.256508]  __dev_queue_xmit+0x1a7e/0x3090
[  343.257083]  ? netdev_core_pick_tx+0x300/0x300
[  343.257690]  ? check_kcov_mode+0x10/0x40
[  343.258219]  ? _raw_spin_unlock_irqrestore+0x29/0x40
[  343.258899]  ? __kasan_init_slab_obj+0x24/0x30
[  343.259529]  ? setup_object.isra.71+0x23/0x90
[  343.260121]  ? new_slab+0x26e/0x4b0
[  343.260609]  ? kasan_poison+0x3a/0x50
[  343.261118]  ? kasan_unpoison+0x28/0x50
[  343.261637]  ? __kasan_slab_alloc+0x71/0x90
[  343.262214]  ? memcpy+0x4d/0x60
[  343.262674]  ? write_comp_data+0x2f/0x90
[  343.263209]  ? __kasan_check_write+0x14/0x20
[  343.263802]  ? __skb_clone+0x5d6/0x840
[  343.264329]  ? __sanitizer_cov_trace_pc+0x21/0x60
[  343.264958]  dev_queue_xmit+0x1c/0x20
[  343.265470]  netlink_deliver_tap+0x652/0x9c0
[  343.266067]  netlink_unicast+0x5a0/0x7f0
[  343.266608]  ? netlink_attachskb+0x860/0x860
[  343.267183]  ? __sanitizer_cov_trace_pc+0x21/0x60
[  343.267820]  ? write_comp_data+0x2f/0x90
[  343.268367]  netlink_sendmsg+0x922/0xe80
[  343.268899]  ? netlink_unicast+0x7f0/0x7f0
[  343.269472]  ? __sanitizer_cov_trace_pc+0x21/0x60
[  343.270099]  ? write_comp_data+0x2f/0x90
[  343.270644]  ? netlink_unicast+0x7f0/0x7f0
[  343.271210]  sock_sendmsg+0x155/0x190
[  343.271721]  ____sys_sendmsg+0x75f/0x8f0
[  343.272262]  ? kernel_sendmsg+0x60/0x60
[  343.272788]  ? write_comp_data+0x2f/0x90
[  343.273332]  ? write_comp_data+0x2f/0x90
[  343.273869]  ___sys_sendmsg+0x10f/0x190
[  343.274405]  ? sendmsg_copy_msghdr+0x80/0x80
[  343.274984]  ? slab_post_alloc_hook+0x70/0x230
[  343.275597]  ? futex_wait_setup+0x240/0x240
[  343.276175]  ? security_file_alloc+0x3e/0x170
[  343.276779]  ? write_comp_data+0x2f/0x90
[  343.277313]  ? __sanitizer_cov_trace_pc+0x21/0x60
[  343.277969]  ? write_comp_data+0x2f/0x90
[  343.278515]  ? __fget_files+0x1ad/0x260
[  343.279048]  ? __sanitizer_cov_trace_pc+0x21/0x60
[  343.279685]  ? write_comp_data+0x2f/0x90
[  343.280234]  ? __sanitizer_cov_trace_pc+0x21/0x60
[  343.280874]  ? sockfd_lookup_light+0xd1/0x190
[  343.281481]  __sys_sendmsg+0x118/0x200
[  343.281998]  ? __sys_sendmsg_sock+0x40/0x40
[  343.282578]  ? alloc_fd+0x229/0x5e0
[  343.283070]  ? write_comp_data+0x2f/0x90
[  343.283610]  ? write_comp_data+0x2f/0x90
[  343.284135]  ? __sanitizer_cov_trace_pc+0x21/0x60
[  343.284776]  ? ktime_get_coarse_real_ts64+0xb8/0xf0
[  343.285450]  __x64_sys_sendmsg+0x7d/0xc0
[  343.285981]  ? syscall_enter_from_user_mode+0x4d/0x70
[  343.286664]  do_syscall_64+0x3a/0x80
[  343.287158]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  343.287850] RIP: 0033:0x7fdde24cf289
[  343.288344] Code: 01 00 48 81 c4 80 00 00 00 e9 f1 fe ff ff 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 73 01 c3 48 8b 0d b7 db 2c 00 f7 d8 64 89 01 48
[  343.290729] RSP: 002b:00007fdde2bd6d98 EFLAGS: 00000246 ORIG_RAX:
000000000000002e
[  343.291730] RAX: ffffffffffffffda RBX: 0000000000000000 RCX:
00007fdde24cf289
[  343.292673] RDX: 0000000000000000 RSI: 00000000200000c0 RDI:
0000000000000004
[  343.293618] RBP: 00007fdde2bd6e20 R08: 0000000100000001 R09:
0000000000000000
[  343.294557] R10: 0000000100000001 R11: 0000000000000246 R12:
0000000000000000
[  343.295493] R13: 0000000000021000 R14: 0000000000000000 R15:
00007fdde2bd7700
[  343.296432]  </TASK>
[  343.296735] Modules linked in: sch_netem ip6_vti ip_vti ip_gre ipip
sit ip_tunnel geneve macsec macvtap tap ipvlan macvlan 8021q garp mrp
hsr wireguard libchacha20poly1305 chacha_x86_64 poly1305_x86_64
ip6_udp_tunnel udp_tunnel libblake2s blake2s_x86_64 libblake2s_generic
curve25519_x86_64 libcurve25519_generic libchacha xfrm_interface
xfrm6_tunnel tunnel4 veth netdevsim psample batman_adv nlmon dummy team
bonding tls vcan ip6_gre ip6_tunnel tunnel6 gre tun ip6t_rpfilter
ipt_REJECT nf_reject_ipv4 ip6t_REJECT nf_reject_ipv6 xt_conntrack ip_set
ebtable_nat ebtable_broute ip6table_nat ip6table_mangle
ip6table_security ip6table_raw iptable_nat nf_nat nf_conntrack
nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_security
iptable_raw ebtable_filter ebtables rfkill ip6table_filter ip6_tables
iptable_filter ppdev bochs drm_vram_helper drm_ttm_helper ttm
drm_kms_helper cec parport_pc drm joydev floppy parport sg syscopyarea
sysfillrect sysimgblt i2c_piix4 qemu_fw_cfg fb_sys_fops pcspkr
[  343.297459]  ip_tables xfs virtio_net net_failover failover sd_mod
sr_mod cdrom t10_pi ata_generic pata_acpi ata_piix libata virtio_pci
virtio_pci_legacy_dev serio_raw virtio_pci_modern_dev dm_mirror
dm_region_hash dm_log dm_mod
[  343.311074] Dumping ftrace buffer:
[  343.311532]    (ftrace buffer empty)
[  343.312040] ---[ end trace a2e3db5a6ae05099 ]---
[  343.312691] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem]
[  343.313481] Code: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff
ff 8b 8d 50 ff ff ff 8b 85 58 ff ff ff 48 8b bd 70 ff ff ff 31 d2 2b 4f
74 <f7> f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03
[  343.315893] RSP: 0018:ffff88800bcd7368 EFLAGS: 00010246
[  343.316622] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX:
0000000000000000
[  343.317585] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI:
ffff88800f8eda40
[  343.318549] RBP: ffff88800bcd7458 R08: 0000000000000000 R09:
ffffffff94fb8445
[  343.319503] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12:
0000000000000000
[  343.320455] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15:
0000000000000020
[  343.321414] FS:  00007fdde2bd7700(0000) GS:ffff888109780000(0000)
knlGS:0000000000000000
[  343.322489] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  343.323283] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4:
00000000000006e0
[  343.324264] Kernel panic - not syncing: Fatal exception in interrupt
[  343.333717] Dumping ftrace buffer:
[  343.334175]    (ftrace buffer empty)
[  343.334653] Kernel Offset: 0x13600000 from 0xffffffff81000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[  343.336027] Rebooting in 86400 seconds..

Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Link: https://lore.kernel.org/r/20211129175328.55339-1-harshit.m.mogalapalli@oracle.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-22 09:19:00 +01:00
Eric Dumazet
d4e931feea netlink: annotate data races around nlk->bound
[ Upstream commit 7707a4d01a648e4c655101a469c956cb11273655 ]

While existing code is correct, KCSAN is reporting
a data-race in netlink_insert / netlink_sendmsg [1]

It is correct to read nlk->bound without a lock, as netlink_autobind()
will acquire all needed locks.

[1]
BUG: KCSAN: data-race in netlink_insert / netlink_sendmsg

write to 0xffff8881031c8b30 of 1 bytes by task 18752 on cpu 0:
 netlink_insert+0x5cc/0x7f0 net/netlink/af_netlink.c:597
 netlink_autobind+0xa9/0x150 net/netlink/af_netlink.c:842
 netlink_sendmsg+0x479/0x7c0 net/netlink/af_netlink.c:1892
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg net/socket.c:723 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2392
 ___sys_sendmsg net/socket.c:2446 [inline]
 __sys_sendmsg+0x1ed/0x270 net/socket.c:2475
 __do_sys_sendmsg net/socket.c:2484 [inline]
 __se_sys_sendmsg net/socket.c:2482 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2482
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881031c8b30 of 1 bytes by task 18751 on cpu 1:
 netlink_sendmsg+0x270/0x7c0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg net/socket.c:723 [inline]
 __sys_sendto+0x2a8/0x370 net/socket.c:2019
 __do_sys_sendto net/socket.c:2031 [inline]
 __se_sys_sendto net/socket.c:2027 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:2027
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18751 Comm: syz-executor.0 Not tainted 5.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: da314c9923 ("netlink: Replace rhash_portid with bound")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-10-13 10:10:52 +02:00
Yajun Deng
51fae54d5a netlink: Deal with ESRCH error in nlmsg_notify()
[ Upstream commit fef773fc8110d8124c73a5e6610f89e52814637d ]

Yonghong Song report:
The bpf selftest tc_bpf failed with latest bpf-next.
The following is the command to run and the result:
$ ./test_progs -n 132
[   40.947571] bpf_testmod: loading out-of-tree module taints kernel.
test_tc_bpf:PASS:test_tc_bpf__open_and_load 0 nsec
test_tc_bpf:PASS:bpf_tc_hook_create(BPF_TC_INGRESS) 0 nsec
test_tc_bpf:PASS:bpf_tc_hook_create invalid hook.attach_point 0 nsec
test_tc_bpf_basic:PASS:bpf_obj_get_info_by_fd 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_attach 0 nsec
test_tc_bpf_basic:PASS:handle set 0 nsec
test_tc_bpf_basic:PASS:priority set 0 nsec
test_tc_bpf_basic:PASS:prog_id set 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_attach replace mode 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_query 0 nsec
test_tc_bpf_basic:PASS:handle set 0 nsec
test_tc_bpf_basic:PASS:priority set 0 nsec
test_tc_bpf_basic:PASS:prog_id set 0 nsec
libbpf: Kernel error message: Failed to send filter delete notification
test_tc_bpf_basic:FAIL:bpf_tc_detach unexpected error: -3 (errno 3)
test_tc_bpf:FAIL:test_tc_internal ingress unexpected error: -3 (errno 3)

The failure seems due to the commit
    cfdf0d9ae75b ("rtnetlink: use nlmsg_notify() in rtnetlink_send()")

Deal with ESRCH error in nlmsg_notify() even the report variable is zero.

Reported-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Link: https://lore.kernel.org/r/20210719051816.11762-1-yajun.deng@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22 11:48:03 +02:00
Johannes Berg
59fba11d64 netlink: disable IRQs for netlink_lock_table()
[ Upstream commit 1d482e666b8e74c7555dbdfbfb77205eeed3ff2d ]

Syzbot reports that in mac80211 we have a potential deadlock
between our "local->stop_queue_reasons_lock" (spinlock) and
netlink's nl_table_lock (rwlock). This is because there's at
least one situation in which we might try to send a netlink
message with this spinlock held while it is also possible to
take the spinlock from a hardirq context, resulting in the
following deadlock scenario reported by lockdep:

       CPU0                    CPU1
       ----                    ----
  lock(nl_table_lock);
                               local_irq_disable();
                               lock(&local->queue_stop_reason_lock);
                               lock(nl_table_lock);
  <Interrupt>
    lock(&local->queue_stop_reason_lock);

This seems valid, we can take the queue_stop_reason_lock in
any kind of context ("CPU0"), and call ieee80211_report_ack_skb()
with the spinlock held and IRQs disabled ("CPU1") in some
code path (ieee80211_do_stop() via ieee80211_free_txskb()).

Short of disallowing netlink use in scenarios like these
(which would be rather complex in mac80211's case due to
the deep callchain), it seems the only fix for this is to
disable IRQs while nl_table_lock is held to avoid hitting
this scenario, this disallows the "CPU0" portion of the
reported deadlock.

Note that the writer side (netlink_table_grab()) already
disables IRQs for this lock.

Unfortunately though, this seems like a huge hammer, and
maybe the whole netlink table locking should be reworked.

Reported-by: syzbot+69ff9dff50dcfe14ddd4@syzkaller.appspotmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-16 11:54:57 +02:00
Sean Tranchetti
0845447d9c genetlink: remove genl_bind
[ Upstream commit 1e82a62fec613844da9e558f3493540a5b7a7b67 ]

A potential deadlock can occur during registering or unregistering a
new generic netlink family between the main nl_table_lock and the
cb_lock where each thread wants the lock held by the other, as
demonstrated below.

1) Thread 1 is performing a netlink_bind() operation on a socket. As part
   of this call, it will call netlink_lock_table(), incrementing the
   nl_table_users count to 1.
2) Thread 2 is registering (or unregistering) a genl_family via the
   genl_(un)register_family() API. The cb_lock semaphore will be taken for
   writing.
3) Thread 1 will call genl_bind() as part of the bind operation to handle
   subscribing to GENL multicast groups at the request of the user. It will
   attempt to take the cb_lock semaphore for reading, but it will fail and
   be scheduled away, waiting for Thread 2 to finish the write.
4) Thread 2 will call netlink_table_grab() during the (un)registration
   call. However, as Thread 1 has incremented nl_table_users, it will not
   be able to proceed, and both threads will be stuck waiting for the
   other.

genl_bind() is a noop, unless a genl_family implements the mcast_bind()
function to handle setting up family-specific multicast operations. Since
no one in-tree uses this functionality as Cong pointed out, simply removing
the genl_bind() function will remove the possibility for deadlock, as there
is no attempt by Thread 1 above to take the cb_lock semaphore.

Fixes: c380d9a7af ("genetlink: pass multicast bind/unbind to families")
Suggested-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Johannes Berg <johannes.berg@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sean Tranchetti <stranche@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-22 09:31:58 +02:00
Pablo Neira Ayuso
7aa760f0f5 netlink: Use netlink header as base to calculate bad attribute offset
[ Upstream commit 84b3268027641401bb8ad4427a90a3cce2eb86f5 ]

Userspace might send a batch that is composed of several netlink
messages. The netlink_ack() function must use the pointer to the netlink
header as base to calculate the bad attribute offset.

Fixes: 2d4bc93368 ("netlink: extended ACK reporting")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 07:14:12 +01:00
Nikolay Aleksandrov
0ededb6efa net: netlink: cap max groups which will be considered in netlink_bind()
commit 3a20773beeeeadec41477a5ba872175b778ff752 upstream.

Since nl_groups is a u32 we can't bind more groups via ->bind
(netlink_bind) call, but netlink has supported more groups via
setsockopt() for a long time and thus nlk->ngroups could be over 32.
Recently I added support for per-vlan notifications and increased the
groups to 33 for NETLINK_ROUTE which exposed an old bug in the
netlink_bind() code causing out-of-bounds access on archs where unsigned
long is 32 bits via test_bit() on a local variable. Fix this by capping the
maximum groups in netlink_bind() to BITS_PER_TYPE(u32), effectively
capping them at 32 which is the minimum of allocated groups and the
maximum groups which can be bound via netlink_bind().

CC: Christophe Leroy <christophe.leroy@c-s.fr>
CC: Richard Guy Briggs <rgb@redhat.com>
Fixes: 4f52090052 ("netlink: have netlink per-protocol bind function return an error code.")
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-05 16:42:20 +01:00
YueHaibing
9b8ef421b4 genetlink: Fix a memory leak on error path
[ Upstream commit ceabee6c59943bdd5e1da1a6a20dc7ee5f8113a2 ]

In genl_register_family(), when idr_alloc() fails,
we forget to free the memory we possibly allocate for
family->attrbuf.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 2ae0f17df1 ("genetlink: use idr to track families")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03 06:26:15 +02:00
David S. Miller
c1c8626fce Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net
Lots of overlapping changes, mostly trivial in nature.

The mlxsw conflict was resolving using the example
resolution at:

https://github.com/jpirko/linux_mlxsw/blob/combined_queue/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-05 13:04:31 -07:00
Dmitry Safonov
91874ecf32 netlink: Don't shift on 64 for ngroups
It's legal to have 64 groups for netlink_sock.

As user-supplied nladdr->nl_groups is __u32, it's possible to subscribe
only to first 32 groups.

The check for correctness of .bind() userspace supplied parameter
is done by applying mask made from ngroups shift. Which broke Android
as they have 64 groups and the shift for mask resulted in an overflow.

Fixes: 61f4b23769 ("netlink: Don't shift with UB on nlk->ngroups")
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: netdev@vger.kernel.org
Cc: stable@vger.kernel.org
Reported-and-Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-04 17:52:51 -07:00
David S. Miller
89b1698c93 Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net
The BTF conflicts were simple overlapping changes.

The virtio_net conflict was an overlap of a fix of statistics counter,
happening alongisde a move over to a bonafide statistics structure
rather than counting value on the stack.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-02 10:55:32 -07:00
Jeremy Cline
bc5b6c0b62 netlink: Fix spectre v1 gadget in netlink_create()
'protocol' is a user-controlled value, so sanitize it after the bounds
check to avoid using it for speculative out-of-bounds access to arrays
indexed by it.

This addresses the following accesses detected with the help of smatch:

* net/netlink/af_netlink.c:654 __netlink_create() warn: potential
  spectre issue 'nlk_cb_mutex_keys' [w]

* net/netlink/af_netlink.c:654 __netlink_create() warn: potential
  spectre issue 'nlk_cb_mutex_key_strings' [w]

* net/netlink/af_netlink.c:685 netlink_create() warn: potential spectre
  issue 'nl_table' [w] (local cap)

Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-01 09:50:58 -07:00
Dmitry Safonov
61f4b23769 netlink: Don't shift with UB on nlk->ngroups
On i386 nlk->ngroups might be 32 or 0. Which leads to UB, resulting in
hang during boot.
Check for 0 ngroups and use (unsigned long long) as a type to shift.

Fixes: 7acf9d4237 ("netlink: Do not subscribe to non-existent groups").
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-30 12:42:22 -07:00
Dmitry Safonov
7acf9d4237 netlink: Do not subscribe to non-existent groups
Make ABI more strict about subscribing to group > ngroups.
Code doesn't check for that and it looks bogus.
(one can subscribe to non-existing group)
Still, it's possible to bind() to all possible groups with (-1)

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: netdev@vger.kernel.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-29 12:50:19 -07:00
Florian Westphal
3730cf4dd7 netlink: do not store start function in netlink_cb
->start() is called once when dump is being initialized, there is no
need to store it in netlink_cb.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:04:49 -07:00
Linus Torvalds
a11e1d432b Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-28 10:40:47 -07:00
Kees Cook
6da2ec5605 treewide: kmalloc() -> kmalloc_array()
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Linus Torvalds
408afb8d78 Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull aio updates from Al Viro:
 "Majority of AIO stuff this cycle. aio-fsync and aio-poll, mostly.

  The only thing I'm holding back for a day or so is Adam's aio ioprio -
  his last-minute fixup is trivial (missing stub in !CONFIG_BLOCK case),
  but let it sit in -next for decency sake..."

* 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
  aio: sanitize the limit checking in io_submit(2)
  aio: fold do_io_submit() into callers
  aio: shift copyin of iocb into io_submit_one()
  aio_read_events_ring(): make a bit more readable
  aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way
  aio: take list removal to (some) callers of aio_complete()
  aio: add missing break for the IOCB_CMD_FDSYNC case
  random: convert to ->poll_mask
  timerfd: convert to ->poll_mask
  eventfd: switch to ->poll_mask
  pipe: convert to ->poll_mask
  crypto: af_alg: convert to ->poll_mask
  net/rxrpc: convert to ->poll_mask
  net/iucv: convert to ->poll_mask
  net/phonet: convert to ->poll_mask
  net/nfc: convert to ->poll_mask
  net/caif: convert to ->poll_mask
  net/bluetooth: convert to ->poll_mask
  net/sctp: convert to ->poll_mask
  net/tipc: convert to ->poll_mask
  ...
2018-06-04 13:57:43 -07:00
Christoph Hellwig
db5051ead6 net: convert datagram_poll users tp ->poll_mask
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26 09:16:44 +02:00
Christoph Hellwig
c350637227 proc: introduce proc_create_net{,_data}
Variants of proc_create{,_data} that directly take a struct seq_operations
and deal with network namespaces in ->open and ->release.  All callers of
proc_create + seq_open_net converted over, and seq_{open,release}_net are
removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:24:30 +02:00
YU Bo
ae552ac278 net/netlink: make sure the headers line up actual value output
Making sure the headers line up properly with the actual value output of the command
`cat /proc/net/netlink`

Before the patch:
<sk       Eth Pid    Groups   Rmem     Wmem     Dump     Locks     Drops     Inode
<ffff8cd2c2f7b000 0   909    00000550 0        0        0 2        0        18946

After the patch:
>sk               Eth Pid        Groups   Rmem     Wmem     Dump  Locks    Drops    Inode
>0000000033203952 0   897        00000113 0        0        0     2        0        14906

Signed-off-by: Bo YU <tsu.yubo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-04 13:00:57 -04:00
Eric Dumazet
6091f09c2f netlink: fix uninit-value in netlink_sendmsg
syzbot reported :

BUG: KMSAN: uninit-value in ffs arch/x86/include/asm/bitops.h:432 [inline]
BUG: KMSAN: uninit-value in netlink_sendmsg+0xb26/0x1310 net/netlink/af_netlink.c:1851

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-07 22:32:31 -04:00
David S. Miller
c0b458a946 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c,
we had some overlapping changes:

1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE -->
   MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE

2) In 'net-next' params->log_rq_size is renamed to be
   params->log_rq_mtu_frames.

3) In 'net-next' params->hard_mtu is added.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-01 19:49:34 -04:00
Kirill Tkhai
2f635ceeb2 net: Drop pernet_operations::async
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27 13:18:09 -04:00
Alexander Potapenko
7880287981 netlink: make sure nladdr has correct size in netlink_connect()
KMSAN reports use of uninitialized memory in the case when |alen| is
smaller than sizeof(struct sockaddr_nl), and therefore |nladdr| isn't
fully copied from the userspace.

Signed-off-by: Alexander Potapenko <glider@google.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-25 21:14:51 -04:00
David S. Miller
03fe2debbb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Fun set of conflict resolutions here...

For the mac80211 stuff, these were fortunately just parallel
adds.  Trivially resolved.

In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.

In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.

The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.

The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:

====================

    Due to bug fixes found by the syzkaller bot and taken into the for-rc
    branch after development for the 4.17 merge window had already started
    being taken into the for-next branch, there were fairly non-trivial
    merge issues that would need to be resolved between the for-rc branch
    and the for-next branch.  This merge resolves those conflicts and
    provides a unified base upon which ongoing development for 4.17 can
    be based.

    Conflicts:
            drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
            (IB/mlx5: Fix cleanup order on unload) added to for-rc and
            commit b5ca15ad7e (IB/mlx5: Add proper representors support)
            add as part of the devel cycle both needed to modify the
            init/de-init functions used by mlx5.  To support the new
            representors, the new functions added by the cleanup patch
            needed to be made non-static, and the init/de-init list
            added by the representors patch needed to be modified to
            match the init/de-init list changes made by the cleanup
            patch.
    Updates:
            drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
            prototypes added by representors patch to reflect new function
            names as changed by cleanup patch
            drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
            stage list to match new order from cleanup patch
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 11:31:58 -04:00
Nicolas Dichtel
02a2385f37 netlink: avoid a double skb free in genlmsg_mcast()
nlmsg_multicast() consumes always the skb, thus the original skb must be
freed only when this function is called with a clone.

Fixes: cb9f7a9a5c ("netlink: ensure to loop over all netns in genlmsg_multicast_allns()")
Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-16 12:34:48 -04:00
David S. Miller
f74290fdb3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-02-24 00:04:20 -05:00
Jason A. Donenfeld
b87b6194be netlink: put module reference if dump start fails
Before, if cb->start() failed, the module reference would never be put,
because cb->cb_running is intentionally false at this point. Users are
generally annoyed by this because they can no longer unload modules that
leak references. Also, it may be possible to tediously wrap a reference
counter back to zero, especially since module.c still uses atomic_inc
instead of refcount_inc.

This patch expands the error path to simply call module_put if
cb->start() fails.

Fixes: 41c87425a1 ("netlink: do not set cb_running if dump's start() errs")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-22 14:01:38 -05:00
Kirill Tkhai
b86b47a395 net: Convert netlink_tap_net_ops
These pernet_operations init just allocated net memory,
and they obviously can be executed in parallel in any
others.

v3: New

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-13 10:36:09 -05:00
Kirill Tkhai
83caf62c86 net: Convert genl_pernet_ops
This pernet_operations create and destroy net::genl_sock.
Foreign pernet_operations don't touch it.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-13 10:36:07 -05:00
Kirill Tkhai
194b95d216 net: Convert netlink_net_ops
The methods of netlink_net_ops create and destroy "netlink"
file, which are not interesting for foreigh pernet_operations.
So, netlink_net_ops may safely be made async.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-13 10:36:06 -05:00
Denys Vlasenko
9b2c45d479 net: make getname() functions return length rather than use int* parameter
Changes since v1:
Added changes in these files:
    drivers/infiniband/hw/usnic/usnic_transport.c
    drivers/staging/lustre/lnet/lnet/lib-socket.c
    drivers/target/iscsi/iscsi_target_login.c
    drivers/vhost/net.c
    fs/dlm/lowcomms.c
    fs/ocfs2/cluster/tcp.c
    security/tomoyo/network.c

Before:
All these functions either return a negative error indicator,
or store length of sockaddr into "int *socklen" parameter
and return zero on success.

"int *socklen" parameter is awkward. For example, if caller does not
care, it still needs to provide on-stack storage for the value
it does not need.

None of the many FOO_getname() functions of various protocols
ever used old value of *socklen. They always just overwrite it.

This change drops this parameter, and makes all these functions, on success,
return length of sockaddr. It's always >= 0 and can be differentiated
from an error.

Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.

rpc_sockname() lost "int buflen" parameter, since its only use was
to be passed to kernel_getsockname() as &buflen and subsequently
not used in any way.

Userspace API is not changed.

    text    data     bss      dec     hex filename
30108430 2633624  873672 33615726 200ef6e vmlinux.before.o
30108109 2633612  873672 33615393 200ee21 vmlinux.o

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-bluetooth@vger.kernel.org
CC: linux-decnet-user@lists.sourceforge.net
CC: linux-wireless@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: linux-sctp@vger.kernel.org
CC: linux-nfs@vger.kernel.org
CC: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-12 14:15:04 -05:00
Nicolas Dichtel
cb9f7a9a5c netlink: ensure to loop over all netns in genlmsg_multicast_allns()
Nowadays, nlmsg_multicast() returns only 0 or -ESRCH but this was not the
case when commit 134e63756d was pushed.
However, there was no reason to stop the loop if a netns does not have
listeners.
Returns -ESRCH only if there was no listeners in all netns.

To avoid having the same problem in the future, I didn't take the
assumption that nlmsg_multicast() returns only 0 or -ESRCH.

Fixes: 134e63756d ("genetlink: make netns aware")
CC: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-08 14:03:18 -05:00
David S. Miller
8565d26bcb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The BPF verifier conflict was some minor contextual issue.

The TUN conflict was less trivial.  Cong Wang fixed a memory leak of
tfile->tx_array in 'net'.  This is an skb_array.  But meanwhile in
net-next tun changed tfile->tx_arry into tfile->tx_ring which is a
ptr_ring.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 22:59:33 -05:00
Xin Long
cd443f1e91 netlink: reset extack earlier in netlink_rcv_skb
Move up the extack reset/initialization in netlink_rcv_skb, so that
those 'goto ack' will not skip it. Otherwise, later on netlink_ack
may use the uninitialized extack and cause kernel crash.

Fixes: cbbdf8433a ("netlink: extack needs to be reset each time through loop")
Reported-by: syzbot+03bee3680a37466775e7@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-18 15:14:51 -05:00
David S. Miller
c02b3741eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Overlapping changes all over.

The mini-qdisc bits were a little bit tricky, however.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 00:10:42 -05:00
Alexey Dobriyan
96890d6252 net: delete /proc THIS_MODULE references
/proc has been ignoring struct file_operations::owner field for 10 years.
Specifically, it started with commit 786d7e1612
("Fix rmmod/read/write races in /proc entries"). Notice the chunk where
inode->i_fop is initialized with proxy struct file_operations for
regular files:

	-               if (de->proc_fops)
	-                       inode->i_fop = de->proc_fops;
	+               if (de->proc_fops) {
	+                       if (S_ISREG(inode->i_mode))
	+                               inode->i_fop = &proc_reg_file_ops;
	+                       else
	+                               inode->i_fop = de->proc_fops;
	+               }

VFS stopped pinning module at this point.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-16 15:01:33 -05:00
David Ahern
cbbdf8433a netlink: extack needs to be reset each time through loop
syzbot triggered the WARN_ON in netlink_ack testing the bad_attr value.
The problem is that netlink_rcv_skb loops over the skb repeatedly invoking
the callback and without resetting the extack leaving potentially stale
data. Initializing each time through avoids the WARN_ON.

Fixes: 2d4bc93368 ("netlink: extended ACK reporting")
Reported-by: syzbot+315fa6766d0f7c359327@syzkaller.appspotmail.com
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-15 13:50:07 -05:00
David S. Miller
c30abd5e40 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three sets of overlapping changes, two in the packet scheduler
and one in the meson-gxl PHY driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-16 22:11:55 -05:00
Kevin Cernekee
93c647643b netlink: Add netns check on taps
Currently, a nlmon link inside a child namespace can observe systemwide
netlink activity.  Filter the traffic so that nlmon can only sniff
netlink messages from its own netns.

Test case:

    vpnns -- bash -c "ip link add nlmon0 type nlmon; \
                      ip link set nlmon0 up; \
                      tcpdump -i nlmon0 -q -w /tmp/nlmon.pcap -U" &
    sudo ip xfrm state add src 10.1.1.1 dst 10.1.1.2 proto esp \
        spi 0x1 mode transport \
        auth sha1 0x6162633132330000000000000000000000000000 \
        enc aes 0x00000000000000000000000000000000
    grep --binary abc123 /tmp/nlmon.pcap

Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-11 11:58:18 -05:00
Cong Wang
b1042d3563 netlink: convert netlink tap spinlock to mutex
Both netlink_add_tap() and netlink_remove_tap() are
called in process context, no need to bother spinlock.

Note, in fact, currently we always hold RTNL when calling
these two functions, so we don't need any other lock at
all, but keeping this lock doesn't harm anything.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-11 10:56:55 -05:00
Cong Wang
25e3f70fcb netlink: make netlink tap per netns
nlmon device is not supposed to capture netlink events from
other netns, so instead of filtering events, we can simply
make netlink tap itself per netns.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-11 10:56:55 -05:00
Tom Herbert
97a6ec4ac0 rhashtable: Change rhashtable_walk_start to return void
Most callers of rhashtable_walk_start don't care about a resize event
which is indicated by a return value of -EAGAIN. So calls to
rhashtable_walk_start are wrapped wih code to ignore -EAGAIN. Something
like this is common:

       ret = rhashtable_walk_start(rhiter);
       if (ret && ret != -EAGAIN)
               goto out;

Since zero and -EAGAIN are the only possible return values from the
function this check is pointless. The condition never evaluates to true.

This patch changes rhashtable_walk_start to return void. This simplifies
code for the callers that ignore -EAGAIN. For the few cases where the
caller cares about the resize event, particularly where the table can be
walked in mulitple parts for netlink or seq file dump, the function
rhashtable_walk_start_check has been added that returns -EAGAIN on a
resize event.

Signed-off-by: Tom Herbert <tom@quantonium.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-11 09:58:38 -05:00
Johannes Berg
0c4b916978 netlink: remove unnecessary forward declaration
netlink_skb_destructor() is actually defined before the first usage
in the file, so remove the unnecessary forward declaration.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14 21:51:14 +09:00
Jason A. Donenfeld
0642840b8b af_netlink: ensure that NLMSG_DONE never fails in dumps
The way people generally use netlink_dump is that they fill in the skb
as much as possible, breaking when nla_put returns an error. Then, they
get called again and start filling out the next skb, and again, and so
forth. The mechanism at work here is the ability for the iterative
dumping function to detect when the skb is filled up and not fill it
past the brim, waiting for a fresh skb for the rest of the data.

However, if the attributes are small and nicely packed, it is possible
that a dump callback function successfully fills in attributes until the
skb is of size 4080 (libmnl's default page-sized receive buffer size).
The dump function completes, satisfied, and then, if it happens to be
that this is actually the last skb, and no further ones are to be sent,
then netlink_dump will add on the NLMSG_DONE part:

  nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI);

It is very important that netlink_dump does this, of course. However, in
this example, that call to nlmsg_put_answer will fail, because the
previous filling by the dump function did not leave it enough room. And
how could it possibly have done so? All of the nla_put variety of
functions simply check to see if the skb has enough tailroom,
independent of the context it is in.

In order to keep the important assumptions of all netlink dump users, it
is therefore important to give them an skb that has this end part of the
tail already reserved, so that the call to nlmsg_put_answer does not
fail. Otherwise, library authors are forced to find some bizarre sized
receive buffer that has a large modulo relative to the common sizes of
messages received, which is ugly and buggy.

This patch thus saves the NLMSG_DONE for an additional message, for the
case that things are dangerously close to the brim. This requires
keeping track of the errno from ->dump() across calls.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13 10:17:13 +09:00
David S. Miller
2a171788ba Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-04 09:26:51 +09:00