kernel/net/packet, branch linux-5.1.y

net/packet: fix memory leak in packet_set_ring()

2019-07-03T11:13:41Z

[ Upstream commit 55655e3d1197fff16a7a05088fb0e5eba50eac55 ] syzbot found we can leak memory in packet_set_ring(), if user application provides buggy parameters. Fixes: 7f953ab2ba46 ("af_packet: TX_RING support for TPACKET_V3") Signed-off-by: Eric Dumazet Cc: Sowmini Varadhan Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

af_packet: Block execution of tasks waiting for transmit to complete in AF_PACKET

2019-07-03T11:13:40Z

[ Upstream commit 89ed5b519004a7706f50b70f611edbd3aaacff2c ] When an application is run that: a) Sets its scheduler to be SCHED_FIFO and b) Opens a memory mapped AF_PACKET socket, and sends frames with the MSG_DONTWAIT flag cleared, its possible for the application to hang forever in the kernel. This occurs because when waiting, the code in tpacket_snd calls schedule, which under normal circumstances allows other tasks to run, including ksoftirqd, which in some cases is responsible for freeing the transmitted skb (which in AF_PACKET calls a destructor that flips the status bit of the transmitted frame back to available, allowing the transmitting task to complete). However, when the calling application is SCHED_FIFO, its priority is such that the schedule call immediately places the task back on the cpu, preventing ksoftirqd from freeing the skb, which in turn prevents the transmitting task from detecting that the transmission is complete. We can fix this by converting the schedule call to a completion mechanism. By using a completion queue, we force the calling task, when it detects there are no more frames to send, to schedule itself off the cpu until such time as the last transmitted skb is freed, allowing forward progress to be made. Tested by myself and the reporter, with good results Change Notes: V1->V2: Enhance the sleep logic to support being interruptible and allowing for honoring to SK_SNDTIMEO (Willem de Bruijn) V2->V3: Rearrage the point at which we wait for the completion queue, to avoid needing to check for ph/skb being null at the end of the loop. Also move the complete call to the skb destructor to avoid needing to modify __packet_set_status. Also gate calling complete on packet_read_pending returning zero to avoid multiple calls to complete. (Willem de Bruijn) Move timeo computation within loop, to re-fetch the socket timeout since we also use the timeo variable to record the return code from the wait_for_complete call (Neil Horman) V3->V4: Willem has requested that the control flow be restored to the previous state. Doing so lets us eliminate the need for the po->wait_on_complete flag variable, and lets us get rid of the packet_next_frame function, but introduces another complexity. Specifically, but using the packet pending count, we can, if an applications calls sendmsg multiple times with MSG_DONTWAIT set, each set of transmitted frames, when complete, will cause tpacket_destruct_skb to issue a complete call, for which there will never be a wait_on_completion call. This imbalance will lead to any future call to wait_for_completion here to return early, when the frames they sent may not have completed. To correct this, we need to re-init the completion queue on every call to tpacket_snd before we enter the loop so as to ensure we wait properly for the frames we send in this iteration. Change the timeout and interrupted gotos to out_put rather than out_status so that we don't try to free a non-existant skb Clean up some extra newlines (Willem de Bruijn) Reviewed-by: Willem de Bruijn Signed-off-by: Neil Horman Reported-by: Matteo Croce Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

packet: unconditionally free po->rollover

2019-06-11T10:19:11Z

[ Upstream commit afa0925c6fcc6a8f610e996ca09bc3215048033c ] Rollover used to use a complex RCU mechanism for assignment, which had a race condition. The below patch fixed the bug and greatly simplified the logic. The feature depends on fanout, but the state is private to the socket. Fanout_release returns f only when the last member leaves and the fanout struct is to be freed. Destroy rollover unconditionally, regardless of fanout state. Fixes: 57f015f5eccf2 ("packet: fix crash in fanout_demux_rollover()") Reported-by: syzbot Diagnosed-by: Dmitry Vyukov Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

packet: Fix error path in packet_init

2019-05-16T17:35:37Z

[ Upstream commit 36096f2f4fa05f7678bc87397665491700bae757 ] kernel BUG at lib/list_debug.c:47! invalid opcode: 0000 [#1 CPU: 0 PID: 12914 Comm: rmmod Tainted: G W 5.1.0+ #47 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 RIP: 0010:__list_del_entry_valid+0x53/0x90 Code: 48 8b 32 48 39 fe 75 35 48 8b 50 08 48 39 f2 75 40 b8 01 00 00 00 5d c3 48 89 fe 48 89 c2 48 c7 c7 18 75 fe 82 e8 cb 34 78 ff <0f> 0b 48 89 fe 48 c7 c7 50 75 fe 82 e8 ba 34 78 ff 0f 0b 48 89 f2 RSP: 0018:ffffc90001c2fe40 EFLAGS: 00010286 RAX: 000000000000004e RBX: ffffffffa0184000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff888237a17788 RDI: 00000000ffffffff RBP: ffffc90001c2fe40 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90001c2fe10 R11: 0000000000000000 R12: 0000000000000000 R13: ffffc90001c2fe50 R14: ffffffffa0184000 R15: 0000000000000000 FS: 00007f3d83634540(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555c350ea818 CR3: 0000000231677000 CR4: 00000000000006f0 Call Trace: unregister_pernet_operations+0x34/0x120 unregister_pernet_subsys+0x1c/0x30 packet_exit+0x1c/0x369 [af_packet __x64_sys_delete_module+0x156/0x260 ? lockdep_hardirqs_on+0x133/0x1b0 ? do_syscall_64+0x12/0x1f0 do_syscall_64+0x6e/0x1f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe When modprobe af_packet, register_pernet_subsys fails and does a cleanup, ops->list is set to LIST_POISON1, but the module init is considered to success, then while rmmod it, BUG() is triggered in __list_del_entry_valid which is called from unregister_pernet_subsys. This patch fix error handing path in packet_init to avoid possilbe issue if some error occur. Reported-by: Hulk Robot Signed-off-by: YueHaibing Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

packet: validate msg_namelen in send directly

2019-05-01T15:28:35Z

Packet sockets in datagram mode take a destination address. Verify its length before passing to dev_hard_header. Prior to 2.6.14-rc3, the send code ignored sll_halen. This is established behavior. Directly compare msg_namelen to dev->addr_len. Change v1->v2: initialize addr in all paths Fixes: 6b8d95f1795c4 ("packet: validate address length if non-zero") Suggested-by: David Laight Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller

packet: in recvmsg msg_name return at least sizeof sockaddr_ll

2019-05-01T15:27:55Z

Packet send checks that msg_name is at least sizeof sockaddr_ll. Packet recv must return at least this length, so that its output can be passed unmodified to packet send. This ceased to be true since adding support for lladdr longer than sll_addr. Since, the return value uses true address length. Always return at least sizeof sockaddr_ll, even if address length is shorter. Zero the padding bytes. Change v1->v2: do not overwrite zeroed padding again. use copy_len. Fixes: 0fb375fb9b93 ("[AF_PACKET]: Allow for > 8 byte hardware addresses.") Suggested-by: David Laight Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller

net/packet: Set __GFP_NOWARN upon allocation in alloc_pg_vec

2019-03-20T17:46:50Z

Since commit fc62814d690c ("net/packet: fix 4gb buffer limit due to overflow check") one can now allocate packet ring buffers >= UINT_MAX. However, syzkaller found that that triggers a warning: [ 21.100000] WARNING: CPU: 2 PID: 2075 at mm/page_alloc.c:4584 __alloc_pages_nod0 [ 21.101490] Modules linked in: [ 21.101921] CPU: 2 PID: 2075 Comm: syz-executor.0 Not tainted 5.0.0 #146 [ 21.102784] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.5.1 01/01/2011 [ 21.103887] RIP: 0010:__alloc_pages_nodemask+0x2a0/0x630 [ 21.104640] Code: fe ff ff 65 48 8b 04 25 c0 de 01 00 48 05 90 0f 00 00 41 bd 01 00 00 00 48 89 44 24 48 e9 9c fe 3 [ 21.107121] RSP: 0018:ffff88805e1cf920 EFLAGS: 00010246 [ 21.107819] RAX: 0000000000000000 RBX: ffffffff85a488a0 RCX: 0000000000000000 [ 21.108753] RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 0000000000000000 [ 21.109699] RBP: 1ffff1100bc39f28 R08: ffffed100bcefb67 R09: ffffed100bcefb67 [ 21.110646] R10: 0000000000000001 R11: ffffed100bcefb66 R12: 000000000000000d [ 21.111623] R13: 0000000000000000 R14: ffff88805e77d888 R15: 000000000000000d [ 21.112552] FS: 00007f7c7de05700(0000) GS:ffff88806d100000(0000) knlGS:0000000000000000 [ 21.113612] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.114405] CR2: 000000000065c000 CR3: 000000005e58e006 CR4: 00000000001606e0 [ 21.115367] Call Trace: [ 21.115705] ? __alloc_pages_slowpath+0x21c0/0x21c0 [ 21.116362] alloc_pages_current+0xac/0x1e0 [ 21.116923] kmalloc_order+0x18/0x70 [ 21.117393] kmalloc_order_trace+0x18/0x110 [ 21.117949] packet_set_ring+0x9d5/0x1770 [ 21.118524] ? packet_rcv_spkt+0x440/0x440 [ 21.119094] ? lock_downgrade+0x620/0x620 [ 21.119646] ? __might_fault+0x177/0x1b0 [ 21.120177] packet_setsockopt+0x981/0x2940 [ 21.120753] ? __fget+0x2fb/0x4b0 [ 21.121209] ? packet_release+0xab0/0xab0 [ 21.121740] ? sock_has_perm+0x1cd/0x260 [ 21.122297] ? selinux_secmark_relabel_packet+0xd0/0xd0 [ 21.123013] ? __fget+0x324/0x4b0 [ 21.123451] ? selinux_netlbl_socket_setsockopt+0x101/0x320 [ 21.124186] ? selinux_netlbl_sock_rcv_skb+0x3a0/0x3a0 [ 21.124908] ? __lock_acquire+0x529/0x3200 [ 21.125453] ? selinux_socket_setsockopt+0x5d/0x70 [ 21.126075] ? __sys_setsockopt+0x131/0x210 [ 21.126533] ? packet_release+0xab0/0xab0 [ 21.127004] __sys_setsockopt+0x131/0x210 [ 21.127449] ? kernel_accept+0x2f0/0x2f0 [ 21.127911] ? ret_from_fork+0x8/0x50 [ 21.128313] ? do_raw_spin_lock+0x11b/0x280 [ 21.128800] __x64_sys_setsockopt+0xba/0x150 [ 21.129271] ? lockdep_hardirqs_on+0x37f/0x560 [ 21.129769] do_syscall_64+0x9f/0x450 [ 21.130182] entry_SYSCALL_64_after_hwframe+0x49/0xbe We should allocate with __GFP_NOWARN to handle this. Cc: Kal Conley Cc: Andrey Konovalov Fixes: fc62814d690c ("net/packet: fix 4gb buffer limit due to overflow check") Signed-off-by: Christoph Paasch Signed-off-by: David S. Miller

af_packet: fix the tx skb protocol in raw sockets with ETH_P_ALL

2019-03-19T01:11:40Z

I am using "protocol ip" filters in TC to manipulate TC flower classifiers, which are only available with "protocol ip". However, I faced an issue that packets sent via raw sockets with ETH_P_ALL did not match the ip filters even if they did satisfy the condition (e.g., DHCP offer from dhcpd). I have determined that the behavior was caused by an unexpected value stored in skb->protocol, namely, ETH_P_ALL instead of ETH_P_IP, when packets were sent via raw sockets with ETH_P_ALL set. IMHO, storing ETH_P_ALL in skb->protocol is not appropriate for packets sent via raw sockets because ETH_P_ALL is not a real ether type used on wire, but a virtual one. This patch fixes the tx protocol selection in cases of transmission via raw sockets created with ETH_P_ALL so that it asks the driver to extract protocol from the Ethernet header. Fixes: 75c65772c3 ("net/packet: Ask driver for protocol if not provided by user") Signed-off-by: Yoshiki Komachi Acked-by: Willem de Bruijn Signed-off-by: David S. Miller

packets: Always register packet sk in the same order

2019-03-19T00:58:39Z

When using fanouts with AF_PACKET, the demux functions such as fanout_demux_cpu will return an index in the fanout socket array, which corresponds to the selected socket. The ordering of this array depends on the order the sockets were added to a given fanout group, so for FANOUT_CPU this means sockets are bound to cpus in the order they are configured, which is OK. However, when stopping then restarting the interface these sockets are bound to, the sockets are reassigned to the fanout group in the reverse order, due to the fact that they were inserted at the head of the interface's AF_PACKET socket list. This means that traffic that was directed to the first socket in the fanout group is now directed to the last one after an interface restart. In the case of FANOUT_CPU, traffic from CPU0 will be directed to the socket that used to receive traffic from the last CPU after an interface restart. This commit introduces a helper to add a socket at the tail of a list, then uses it to register AF_PACKET sockets. Note that this changes the order in which sockets are listed in /proc and with sock_diag. Fixes: dc99f600698d ("packet: Add fanout support") Signed-off-by: Maxime Chevallier Acked-by: Willem de Bruijn Signed-off-by: David S. Miller

net/packet: Remove redundant skb->protocol set

2019-02-22T20:55:31Z

c72219b75f introduced tpacket_set_protocol that parses the Ethernet L2 header and sets skb->protocol if it's unset. It is no longer needed since the introduction of packet_parse_headers. In case of SOCK_RAW and unset skb->protocol, packet_parse_headers asks the driver to tell the protocol number, and it's implemented for all Ethernet devices. As the old function supported only Ethernet, no functionality is lost. Signed-off-by: Maxim Mikityanskiy Signed-off-by: David S. Miller