path: root/net/netlink
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2015-09-10netlink, mmap: fix edge-case leakages in nf queue zero-copyDaniel Borkmann1-6/+12
When netlink mmap on receive side is the consumer of nf queue data, it can happen that in some edge cases, we write skb shared info into the user space mmap buffer: Assume a possible rx ring frame size of only 4096, and the network skb, which is being zero-copied into the netlink skb, contains page frags with an overall skb->len larger than the linear part of the netlink skb. skb_zerocopy(), which is generic and thus not aware of the fact that shared info cannot be accessed for such skbs then tries to write and fill frags, thus leaking kernel data/pointers and in some corner cases possibly writing out of bounds of the mmap area (when filling the last slot in the ring buffer this way). I.e. the ring buffer slot is then of status NL_MMAP_STATUS_VALID, has an advertised length larger than 4096, where the linear part is visible at the slot beginning, and the leaked sizeof(struct skb_shared_info) has been written to the beginning of the next slot (also corrupting the struct nl_mmap_hdr slot header incl. status etc), since skb->end points to skb->data + ring->frame_size - NL_MMAP_HDRLEN. The fix adds and lets __netlink_alloc_skb() take the actual needed linear room for the network skb + meta data into account. It's completely irrelevant for non-mmaped netlink sockets, but in case mmap sockets are used, it can be decided whether the available skb_tailroom() is really large enough for the buffer, or whether it needs to internally fallback to a normal alloc_skb(). >From nf queue side, the information whether the destination port is an mmap RX ring is not really available without extra port-to-socket lookup, thus it can only be determined in lower layers i.e. when __netlink_alloc_skb() is called that checks internally for this. I chose to add the extra ldiff parameter as mmap will then still work: We have data_len and hlen in nfqnl_build_packet_message(), data_len is the full length (capped at queue->copy_range) for skb_zerocopy() and hlen some possible part of data_len that needs to be copied; the rem_len variable indicates the needed remaining linear mmap space. The only other workaround in nf queue internally would be after allocation time by f.e. cap'ing the data_len to the skb_tailroom() iff we deal with an mmap skb, but that would 1) expose the fact that we use a mmap skb to upper layers, and 2) trim the skb where we otherwise could just have moved the full skb into the normal receive queue. After the patch, in my test case the ring slot doesn't fit and therefore shows NL_MMAP_STATUS_COPY, where a full skb carries all the data and thus needs to be picked up via recv(). Fixes: 3ab1f683bf8b ("nfnetlink: add support for memory mapped netlink") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-10netlink, mmap: don't walk rx ring on poll if receive queue non-emptyDaniel Borkmann1-5/+12
In case of netlink mmap, there can be situations where received frames have to be placed into the normal receive queue. The ring buffer indicates this through NL_MMAP_STATUS_COPY, so the user is asked to pick them up via recvmsg(2) syscall, and to put the slot back to NL_MMAP_STATUS_UNUSED. Commit 0ef707700f1c ("netlink: rx mmap: fix POLLIN condition") changed polling, so that we walk in the worst case the whole ring through the new netlink_has_valid_frame(), for example, when the ring would have no NL_MMAP_STATUS_VALID, but at least one NL_MMAP_STATUS_COPY frame. Since we do a datagram_poll() already earlier to pick up a mask that could possibly contain POLLIN | POLLRDNORM already (due to NL_MMAP_STATUS_COPY), we can skip checking the rx ring entirely. In case the kernel is compiled with !CONFIG_NETLINK_MMAP, then all this is irrelevant anyway as netlink_poll() is just defined as datagram_poll(). Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-31netlink: rx mmap: fix POLLIN conditionKen-ichirou MATSUZAWA1-12/+16
Poll() returns immediately after setting the kernel current frame (ring->head) to SKIP from user space even though there is no new frame. And in a case of all frames is VALID, user space program unintensionally sets (only) kernel current frame to UNUSED, then calls poll(), it will not return immediately even though there are VALID frames. To avoid situations like above, I think we need to scan all frames to find VALID frames at poll() like netlink_alloc_skb(), netlink_forward_ring() finding an UNUSED frame at skb allocation. Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-29netlink: mmap: fix lookup frame positionKen-ichirou MATSUZAWA1-2/+2
__netlink_lookup_frame() was always called with the same "pos" value in netlink_forward_ring(). It will look at the same ring entry header over and over again, every time through this loop. Then cycle through the whole ring, advancing ring->head, not "pos" until it equals the "ring->head != head" loop test fails. Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-29netlink: add NETLINK_CAP_ACK socket optionChristophe Ricard1-3/+24
Since commit c05cdb1b864f ("netlink: allow large data transfers from user-space"), the kernel may fail to allocate the necessary room for the acknowledgment message back to userspace. This patch introduces a new socket option that trims off the payload of the original netlink message. The netlink message header is still included, so the user can guess from the sequence number what is the message that has triggered the acknowledgment. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-23netlink: mmap: fix tx type checkKen-ichirou MATSUZAWA1-1/+1
I can't send netlink message via mmaped netlink socket since commit: a8866ff6a5bce7d0ec465a63bc482a85c09b0d39 netlink: make the check for "send from tx_ring" deterministic msg->msg_iter.type is set to WRITE (1) at SYSCALL_DEFINE6(sendto, ... import_single_range(WRITE, ... iov_iter_init(1, WRITE, ... call path, so that we need to check the type by iter_is_iovec() to accept the WRITE. Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10netlink: make sure -EBUSY won't escape from netlink_insertDaniel Borkmann1-0/+5
Linus reports the following deadlock on rtnl_mutex; triggered only once so far (extract): [12236.694209] NetworkManager D 0000000000013b80 0 1047 1 0x00000000 [12236.694218] ffff88003f902640 0000000000000000 ffffffff815d15a9 0000000000000018 [12236.694224] ffff880119538000 ffff88003f902640 ffffffff81a8ff84 00000000ffffffff [12236.694230] ffffffff81a8ff88 ffff880119c47f00 ffffffff815d133a ffffffff81a8ff80 [12236.694235] Call Trace: [12236.694250] [<ffffffff815d15a9>] ? schedule_preempt_disabled+0x9/0x10 [12236.694257] [<ffffffff815d133a>] ? schedule+0x2a/0x70 [12236.694263] [<ffffffff815d15a9>] ? schedule_preempt_disabled+0x9/0x10 [12236.694271] [<ffffffff815d2c3f>] ? __mutex_lock_slowpath+0x7f/0xf0 [12236.694280] [<ffffffff815d2cc6>] ? mutex_lock+0x16/0x30 [12236.694291] [<ffffffff814f1f90>] ? rtnetlink_rcv+0x10/0x30 [12236.694299] [<ffffffff8150ce3b>] ? netlink_unicast+0xfb/0x180 [12236.694309] [<ffffffff814f5ad3>] ? rtnl_getlink+0x113/0x190 [12236.694319] [<ffffffff814f202a>] ? rtnetlink_rcv_msg+0x7a/0x210 [12236.694331] [<ffffffff8124565c>] ? sock_has_perm+0x5c/0x70 [12236.694339] [<ffffffff814f1fb0>] ? rtnetlink_rcv+0x30/0x30 [12236.694346] [<ffffffff8150d62c>] ? netlink_rcv_skb+0x9c/0xc0 [12236.694354] [<ffffffff814f1f9f>] ? rtnetlink_rcv+0x1f/0x30 [12236.694360] [<ffffffff8150ce3b>] ? netlink_unicast+0xfb/0x180 [12236.694367] [<ffffffff8150d344>] ? netlink_sendmsg+0x484/0x5d0 [12236.694376] [<ffffffff810a236f>] ? __wake_up+0x2f/0x50 [12236.694387] [<ffffffff814cad23>] ? sock_sendmsg+0x33/0x40 [12236.694396] [<ffffffff814cb05e>] ? ___sys_sendmsg+0x22e/0x240 [12236.694405] [<ffffffff814cab75>] ? ___sys_recvmsg+0x135/0x1a0 [12236.694415] [<ffffffff811a9d12>] ? eventfd_write+0x82/0x210 [12236.694423] [<ffffffff811a0f9e>] ? fsnotify+0x32e/0x4c0 [12236.694429] [<ffffffff8108cb70>] ? wake_up_q+0x60/0x60 [12236.694434] [<ffffffff814cba09>] ? __sys_sendmsg+0x39/0x70 [12236.694440] [<ffffffff815d4797>] ? entry_SYSCALL_64_fastpath+0x12/0x6a It seems so far plausible that the recursive call into rtnetlink_rcv() looks suspicious. One way, where this could trigger is that the senders NETLINK_CB(skb).portid was wrongly 0 (which is rtnetlink socket), so the rtnl_getlink() request's answer would be sent to the kernel instead to the actual user process, thus grabbing rtnl_mutex() twice. One theory would be that netlink_autobind() triggered via netlink_sendmsg() internally overwrites the -EBUSY error to 0, but where it is wrongly originating from __netlink_insert() instead. That would reset the socket's portid to 0, which is then filled into NETLINK_CB(skb).portid later on. As commit d470e3b483dc ("[NETLINK]: Fix two socket hashing bugs.") also puts it, -EBUSY should not be propagated from netlink_insert(). It looks like it's very unlikely to reproduce. We need to trigger the rhashtable_insert_rehash() handler under a situation where rehashing currently occurs (one /rare/ way would be to hit ht->elasticity limits while not filled enough to expand the hashtable, but that would rather require a specifically crafted bind() sequence with knowledge about destination slots, seems unlikely). It probably makes sense to guard __netlink_insert() in any case and remap that error. It was suggested that EOVERFLOW might be better than an already overloaded ENOMEM. Reference: http://thread.gmane.org/gmane.linux.network/372676 Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-22netlink: don't hold mutex in rcu callback when releasing mmapd ringFlorian Westphal1-32/+47
Kirill A. Shutemov says: This simple test-case trigers few locking asserts in kernel: int main(int argc, char **argv) { unsigned int block_size = 16 * 4096; struct nl_mmap_req req = { .nm_block_size = block_size, .nm_block_nr = 64, .nm_frame_size = 16384, .nm_frame_nr = 64 * block_size / 16384, }; unsigned int ring_size; int fd; fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (setsockopt(fd, SOL_NETLINK, NETLINK_RX_RING, &req, sizeof(req)) < 0) exit(1); if (setsockopt(fd, SOL_NETLINK, NETLINK_TX_RING, &req, sizeof(req)) < 0) exit(1); ring_size = req.nm_block_nr * req.nm_block_size; mmap(NULL, 2 * ring_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); return 0; } +++ exited with 0 +++ BUG: sleeping function called from invalid context at /home/kas/git/public/linux-mm/kernel/locking/mutex.c:616 in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: init 3 locks held by init/1: #0: (reboot_mutex){+.+...}, at: [<ffffffff81080959>] SyS_reboot+0xa9/0x220 #1: ((reboot_notifier_list).rwsem){.+.+..}, at: [<ffffffff8107f379>] __blocking_notifier_call_chain+0x39/0x70 #2: (rcu_callback){......}, at: [<ffffffff810d32e0>] rcu_do_batch.isra.49+0x160/0x10c0 Preemption disabled at:[<ffffffff8145365f>] __delay+0xf/0x20 CPU: 1 PID: 1 Comm: init Not tainted 4.1.0-00009-gbddf4c4818e0 #253 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Debian-1.8.2-1 04/01/2014 ffff88017b3d8000 ffff88027bc03c38 ffffffff81929ceb 0000000000000102 0000000000000000 ffff88027bc03c68 ffffffff81085a9d 0000000000000002 ffffffff81ca2a20 0000000000000268 0000000000000000 ffff88027bc03c98 Call Trace: <IRQ> [<ffffffff81929ceb>] dump_stack+0x4f/0x7b [<ffffffff81085a9d>] ___might_sleep+0x16d/0x270 [<ffffffff81085bed>] __might_sleep+0x4d/0x90 [<ffffffff8192e96f>] mutex_lock_nested+0x2f/0x430 [<ffffffff81932fed>] ? _raw_spin_unlock_irqrestore+0x5d/0x80 [<ffffffff81464143>] ? __this_cpu_preempt_check+0x13/0x20 [<ffffffff8182fc3d>] netlink_set_ring+0x1ed/0x350 [<ffffffff8182e000>] ? netlink_undo_bind+0x70/0x70 [<ffffffff8182fe20>] netlink_sock_destruct+0x80/0x150 [<ffffffff817e484d>] __sk_free+0x1d/0x160 [<ffffffff817e49a9>] sk_free+0x19/0x20 [..] Cong Wang says: We can't hold mutex lock in a rcu callback, [..] Thomas Graf says: The socket should be dead at this point. It might be simpler to add a netlink_release_ring() function which doesn't require locking at all. Reported-by: "Kirill A. Shutemov" <kirill@shutemov.name> Diagnosed-by: Cong Wang <cwang@twopensource.com> Suggested-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-03netlink: Delete an unnecessary check before the function call "module_put"Markus Elfring1-1/+1
The module_put() function tests whether its argument is NULL and then returns immediately. Thus the test around the call is not needed. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-21netlink: add API to retrieve all group membershipsDavid Herrmann1-0/+22
This patch adds getsockopt(SOL_NETLINK, NETLINK_LIST_MEMBERSHIPS) to retrieve all groups a socket is a member of. Currently, we have to use getsockname() and look at the nl.nl_groups bitmask. However, this mask is limited to 32 groups. Hence, similar to NETLINK_ADD_MEMBERSHIP and NETLINK_DROP_MEMBERSHIP, this adds a separate sockopt to manager higher groups IDs than 32. This new NETLINK_LIST_MEMBERSHIPS option takes a pointer to __u32 and the size of the array. The array is filled with the full membership-set of the socket, and the required array size is returned in optlen. Hence, user-space can retry with a properly sized array in case it was too small. Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+2
Conflicts: drivers/net/ethernet/cadence/macb.c drivers/net/phy/phy.c include/linux/skbuff.h net/ipv4/tcp.c net/switchdev/switchdev.c Switchdev was a case of RTNH_H_{EXTERNAL --> OFFLOAD} renaming overlapping with net-next changes of various sorts. phy.c was a case of two changes, one adding a local variable to a function whilst the second was removing one. tcp.c overlapped a deadlock fix with the addition of new tcp_info statistic values. macb.c involved the addition of two zyncq device entries. skbuff.h involved adding back ipv4_daddr to nf_bridge_info whilst net-next changes put two other existing members of that struct into a union. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-18netlink: Use random autobind roverHerbert Xu1-6/+10
Currently we use a global rover to select a port ID that is unique. This used to work consistently when it was protected with a global lock. However as we're now lockless, the global rover can exhibit pathological behaviour should multiple threads all stomp on it at the same time. Granted this will eventually resolve itself but the process is suboptimal. This patch replaces the global rover with a pseudorandom starting point to avoid this issue. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-16netlink: Reset portid after netlink_insert failureHerbert Xu1-0/+1
The commit c5adde9468b0714a051eac7f9666f23eb10b61f7 ("netlink: eliminate nl_sk_hash_lock") breaks the autobind retry mechanism because it doesn't reset portid after a failed netlink_insert. This means that should autobind fail the first time around, then the socket will be stuck in limbo as it can never be bound again since it already has a non-zero portid. Fixes: c5adde9468b0 ("netlink: eliminate nl_sk_hash_lock") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14netlink: move nl_table in read_mostly sectionEric Dumazet1-1/+1
netlink sockets creation and deletion heavily modify nl_table_users and nl_table_lock. If nl_table is sharing one cache line with one of them, netlink performance is really bad on SMP. ffffffff81ff5f00 B nl_table ffffffff81ff5f0c b nl_table_users Putting nl_table in read_mostly section increased performance of my open/delete netlink sockets test by about 80 % This came up while diagnosing a getaddrinfo() problem. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+0
Four minor merge conflicts: 1) qca_spi.c renamed the local variable used for the SPI device from spi_device to spi, meanwhile the spi_set_drvdata() call got moved further up in the probe function. 2) Two changes were both adding new members to codel params structure, and thus we had overlapping changes to the initializer function. 3) 'net' was making a fix to sk_release_kernel() which is completely removed in 'net-next'. 4) In net_namespace.c, the rtnl_net_fill() call for GET operations had the command value fixed, meanwhile 'net-next' adjusted the argument signature a bit. This also matches example merge resolutions posted by Stephen Rothwell over the past two days. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11netlink: Create kernel netlink sockets in the proper network namespaceEric W. Biederman1-8/+6
Utilize the new functionality of sk_alloc so that nothing needs to be done to suprress the reference counting on kernel sockets. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11net: Pass kern from net_proto_family.create to sk_allocEric W. Biederman1-6/+5
In preparation for changing how struct net is refcounted on kernel sockets pass the knowledge that we are creating a kernel socket from sock_create_kern through to sk_alloc. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-10netlink: allow to listen "all" netnsNicolas Dichtel1-5/+47
More accurately, listen all netns that have a nsid assigned into the netns where the netlink socket is opened. For this purpose, a netlink socket option is added: NETLINK_LISTEN_ALL_NSID. When this option is set on a netlink socket, this socket will receive netlink notifications from all netns that have a nsid assigned into the netns where the socket has been opened. The nsid is sent to userland via an anscillary data. With this patch, a daemon needs only one socket to listen many netns. This is useful when the number of netns is high. Because 0 is a valid value for a nsid, the field nsid_is_set indicates if the field nsid is valid or not. skb->cb is initialized to 0 on skb allocation, thus we are sure that we will never send a nsid 0 by error to the userland. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-10netlink: rename private flags and statesNicolas Dichtel1-29/+30
These flags and states have the same prefix (NETLINK_) that netlink socket options. To avoid confusion and to be able to name a flag like a socket option, let's use an other prefix: NETLINK_[S|F]_. Note: a comment has been fixed, it was talking about NETLINK_RECV_NO_ENOBUFS socket option instead of NETLINK_NO_ENOBUFS. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-04netlink: Remove max_size settingHerbert Xu1-1/+0
We currently limit the hash table size to 64K which is very bad as even 10 years ago it was relatively easy to generate millions of sockets. Since the hash table is naturally limited by memory allocation failure, we don't really need an explicit limit so this patch removes it. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Thomas Graf <tgraf@noironetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-25net: fix crash in build_skb()Eric Dumazet1-4/+2
When I added pfmemalloc support in build_skb(), I forgot netlink was using build_skb() with a vmalloc() area. In this patch I introduce __build_skb() for netlink use, and build_skb() is a wrapper handling both skb->head_frag and skb->pfmemalloc This means netlink no longer has to hack skb->head_frag [ 1567.700067] kernel BUG at arch/x86/mm/physaddr.c:26! [ 1567.700067] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 1567.700067] Dumping ftrace buffer: [ 1567.700067] (ftrace buffer empty) [ 1567.700067] Modules linked in: [ 1567.700067] CPU: 9 PID: 16186 Comm: trinity-c182 Not tainted 4.0.0-next-20150424-sasha-00037-g4796e21 #2167 [ 1567.700067] task: ffff880127efb000 ti: ffff880246770000 task.ti: ffff880246770000 [ 1567.700067] RIP: __phys_addr (arch/x86/mm/physaddr.c:26 (discriminator 3)) [ 1567.700067] RSP: 0018:ffff8802467779d8 EFLAGS: 00010202 [ 1567.700067] RAX: 000041000ed8e000 RBX: ffffc9008ed8e000 RCX: 000000000000002c [ 1567.700067] RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffffffffb3fd6049 [ 1567.700067] RBP: ffff8802467779f8 R08: 0000000000000019 R09: ffff8801d0168000 [ 1567.700067] R10: ffff8801d01680c7 R11: ffffed003a02d019 R12: ffffc9000ed8e000 [ 1567.700067] R13: 0000000000000f40 R14: 0000000000001180 R15: ffffc9000ed8e000 [ 1567.700067] FS: 00007f2a7da3f700(0000) GS:ffff8801d1000000(0000) knlGS:0000000000000000 [ 1567.700067] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1567.700067] CR2: 0000000000738308 CR3: 000000022e329000 CR4: 00000000000007e0 [ 1567.700067] Stack: [ 1567.700067] ffffc9000ed8e000 ffff8801d0168000 ffffc9000ed8e000 ffff8801d0168000 [ 1567.700067] ffff880246777a28 ffffffffad7c0a21 0000000000001080 ffff880246777c08 [ 1567.700067] ffff88060d302e68 ffff880246777b58 ffff880246777b88 ffffffffad9a6821 [ 1567.700067] Call Trace: [ 1567.700067] build_skb (include/linux/mm.h:508 net/core/skbuff.c:316) [ 1567.700067] netlink_sendmsg (net/netlink/af_netlink.c:1633 net/netlink/af_netlink.c:2329) [ 1567.774369] ? sched_clock_cpu (kernel/sched/clock.c:311) [ 1567.774369] ? netlink_unicast (net/netlink/af_netlink.c:2273) [ 1567.774369] ? netlink_unicast (net/netlink/af_netlink.c:2273) [ 1567.774369] sock_sendmsg (net/socket.c:614 net/socket.c:623) [ 1567.774369] sock_write_iter (net/socket.c:823) [ 1567.774369] ? sock_sendmsg (net/socket.c:806) [ 1567.774369] __vfs_write (fs/read_write.c:479 fs/read_write.c:491) [ 1567.774369] ? get_lock_stats (kernel/locking/lockdep.c:249) [ 1567.774369] ? default_llseek (fs/read_write.c:487) [ 1567.774369] ? vtime_account_user (kernel/sched/cputime.c:701) [ 1567.774369] ? rw_verify_area (fs/read_write.c:406 (discriminator 4)) [ 1567.774369] vfs_write (fs/read_write.c:539) [ 1567.774369] SyS_write (fs/read_write.c:586 fs/read_write.c:577) [ 1567.774369] ? SyS_read (fs/read_write.c:577) [ 1567.774369] ? __this_cpu_preempt_check (lib/smp_processor_id.c:63) [ 1567.774369] ? trace_hardirqs_on_caller (kernel/locking/lockdep.c:2594 kernel/locking/lockdep.c:2636) [ 1567.774369] ? trace_hardirqs_on_thunk (arch/x86/lib/thunk_64.S:42) [ 1567.774369] system_call_fastpath (arch/x86/kernel/entry_64.S:261) Fixes: 79930f5892e ("net: do not deplete pfmemalloc reserve") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-25rhashtable: provide len to obj_hashfnPatrick McHardy1-1/+1
nftables sets will be converted to use so called setextensions, moving the key to a non-fixed position. To hash it, the obj_hashfn must be used, however it so far doesn't receive the length parameter. Pass the key length to obj_hashfn() and convert existing users. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-03-24rhashtable: Disable automatic shrinking by defaultThomas Graf1-0/+1
Introduce a new bool automatic_shrinking to require the user to explicitly opt-in to automatic shrinking of tables. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-24netlink: Use default rhashtable hashfnHerbert Xu1-2/+1
This patch removes the explicit jhash value for the hashfn parameter of rhashtable. As the key length is a multiple of 4, this means that we will actually end up using jhash2. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-21netlink: Remove netlink_compare_arg.trailerHerbert Xu1-2/+3
Instead of computing the offset from trailer, this patch computes netlink_compare_arg_len from the offset of portid and then adds 4 to it. This allows trailer to be removed. Reported-by: David Miller <davem@davemloft.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-20netlink: Move namespace into hash keyHerbert Xu1-32/+56
Currently the name space is a de facto key because it has to match before we find an object in the hash table. However, it isn't in the hash value so all objects from different name spaces with the same port ID hash to the same bucket. This is bad as the number of name spaces is unbounded. This patch fixes this by using the namespace when doing the hash. Because the namespace field doesn't lie next to the portid field in the netlink socket, this patch switches over to the rhashtable interface without a fixed key. This patch also uses the new inlined rhashtable interface where possible. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18netlink: Use rhashtable max_size instead of max_shiftHerbert Xu1-1/+1
This patch converts netlink to use rhashtable max_size instead of the obsolete max_shift. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+0
Conflicts: drivers/net/ethernet/rocker/rocker.c The rocker commit was two overlapping changes, one to rename the ->vport member to ->pport, and another making the bitmask expression use '1ULL' instead of plain '1'. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02net: Remove iocb argument from sendmsg and recvmsgYing Xue1-4/+2
After TIPC doesn't depend on iocb argument in its internal implementations of sendmsg() and recvmsg() hooks defined in proto structure, no any user is using iocb argument in them at all now. Then we can drop the redundant iocb argument completely from kinds of implementations of both sendmsg() and recvmsg() in the entire networking stack. Cc: Christoph Hellwig <hch@lst.de> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27rhashtable: remove indirection for grow/shrink decision functionsDaniel Borkmann1-2/+0
Currently, all real users of rhashtable default their grow and shrink decision functions to rht_grow_above_75() and rht_shrink_below_30(), so that there's currently no need to have this explicitly selectable. It can/should be generic and private inside rhashtable until a real use case pops up. Since we can make this private, we'll save us this additional indirection layer and can improve insertion/deletion time as well. Reference: http://patchwork.ozlabs.org/patch/443040/ Suggested-by: David S. Miller <davem@davemloft.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+2
Conflicts: drivers/net/vxlan.c drivers/vhost/net.c include/linux/if_vlan.h net/core/dev.c The net/core/dev.c conflict was the overlap of one commit marking an existing function static whilst another was adding a new function. In the include/linux/if_vlan.h case, the type used for a local variable was changed in 'net', whereas the function got rewritten to fix a stacked vlan bug in 'net-next'. In drivers/vhost/net.c, Al Viro's iov_iter conversions in 'net-next' overlapped with an endainness fix for VHOST 1.0 in 'net'. In drivers/net/vxlan.c, vxlan_find_vni() added a 'flags' parameter in 'net-next' whereas in 'net' there was a bug fix to pass in the correct network namespace pointer in calls to this function. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05Merge branch 'for-davem' of ↵David S. Miller1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs More iov_iter work from Al Viro. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05netlink: Use rhashtable walk iteratorHerbert Xu1-66/+64
This patch gets rid of the manual rhashtable walk in netlink which touches rhashtable internals that should not be exposed. It does so by using the rhashtable iterator primitives. In fact the existing code was very buggy. Some sockets weren't shown at all while others were shown more than once. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-04netlink: make the check for "send from tx_ring" deterministicAl Viro1-0/+5
As it is, zero msg_iovlen means that the first iovec in the kernel array of iovecs is left uninitialized, so checking if its ->iov_base is NULL is random. Since the real users of that thing are doing sendto(fd, NULL, 0, ...), they are getting msg_iovlen = 1 and msg_iov[0] = {NULL, 0}, which is what this test is trying to catch. As suggested by davem, let's just check that msg_iovlen was 1 and msg_iov[0].iov_base was NULL - _that_ is well-defined and it catches what we want to catch. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-01-31netlink: fix wrong subscription bitmask to group mapping inPablo Neira1-2/+2
The subscription bitmask passed via struct sockaddr_nl is converted to the group number when calling the netlink_bind() and netlink_unbind() callbacks. The conversion is however incorrect since bitmask (1 << 0) needs to be mapped to group number 1. Note that you cannot specify the group number 0 (usually known as _NONE) from setsockopt() using NETLINK_ADD_MEMBERSHIP since this is rejected through -EINVAL. This problem became noticeable since 97840cb ("netfilter: nfnetlink: fix insufficient validation in nfnetlink_bind") when binding to bitmask (1 << 0) in ctnetlink. Reported-by: Andre Tomt <andre@tomt.net> Reported-by: Ivan Delalande <colona@arista.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-29net: remove sock_iocbChristoph Hellwig1-18/+10
The sock_iocb structure is allocate on stack for each read/write-like operation on sockets, and contains various fields of which only the embedded msghdr and sometimes a pointer to the scm_cookie is ever used. Get rid of the sock_iocb and put a msghdr directly on the stack and pass the scm_cookie explicitly to netlink_mmap_sendmsg. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller3-15/+28
Conflicts: arch/arm/boot/dts/imx6sx-sdb.dts net/sched/cls_bpf.c Two simple sets of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-27netlink: Kill redundant net argument in netlink_insertHerbert Xu1-8/+7
The socket already carries the net namespace with it so there is no need to be passing another net around. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18netlink: make nlmsg_end() and genlmsg_end() voidJohannes Berg2-3/+6
Contrary to common expectations for an "int" return, these functions return only a positive value -- if used correctly they cannot even return 0 because the message header will necessarily be in the skb. This makes the very common pattern of if (genlmsg_end(...) < 0) { ... } be a whole bunch of dead code. Many places also simply do return nlmsg_end(...); and the caller is expected to deal with it. This also commonly (at least for me) causes errors, because it is very common to write if (my_function(...)) /* error condition */ and if my_function() does "return nlmsg_end()" this is of course wrong. Additionally, there's not a single place in the kernel that actually needs the message length returned, and if anyone needs it later then it'll be very easy to just use skb->len there. Remove this, and make the functions void. This removes a bunch of dead code as described above. The patch adds lines because I did - return nlmsg_end(...); + nlmsg_end(...); + return 0; I could have preserved all the function's return values by returning skb->len, but instead I've audited all the places calling the affected functions and found that none cared. A few places actually compared the return value with <= 0 in dump functionality, but that could just be changed to < 0 with no change in behaviour, so I opted for the more efficient version. One instance of the error I've made numerous times now is also present in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't check for <0 or <=0 and thus broke out of the loop every single time. I've preserved this since it will (I think) have caused the messages to userspace to be formatted differently with just a single message for every SKB returned to userspace. It's possible that this isn't needed for the tools that actually use this, but I don't even know what they are so couldn't test that changing this behaviour would be acceptable. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-16genetlink: synchronize socket closing and family removalJohannes Berg3-14/+27
In addition to the problem Jeff Layton reported, I looked at the code and reproduced the same warning by subscribing and removing the genl family with a socket still open. This is a fairly tricky race which originates in the fact that generic netlink allows the family to go away while sockets are still open - unlike regular netlink which has a module refcount for every open socket so in general this cannot be triggered. Trying to resolve this issue by the obvious locking isn't possible as it will result in deadlocks between unregistration and group unbind notification (which incidentally lockdep doesn't find due to the home grown locking in the netlink table.) To really resolve this, introduce a "closing socket" reference counter (for generic netlink only, as it's the only affected family) in the core netlink code and use that in generic netlink to wait for all the sockets that are being closed at the same time as a generic netlink family is removed. This fixes the race that when a socket is closed, it will should call the unbind, but if the family is removed at the same time the unbind will not find it, leading to the warning. The real problem though is that in this case the unbind could actually find a new family that is registered to have a multicast group with the same ID, and call its mcast_unbind() leading to confusing. Also remove the warning since it would still trigger, but is now no longer a problem. This also moves the code in af_netlink.c to before unreferencing the module to avoid having the same problem in the normal non-genl case. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-16genetlink: disallow subscribing to unknown mcast groupsJohannes Berg1-1/+1
Jeff Layton reported that he could trigger the multicast unbind warning in generic netlink using trinity. I originally thought it was a race condition between unregistering the generic netlink family and closing the socket, but there's a far simpler explanation: genetlink currently allows subscribing to groups that don't (yet) exist, and the warning is triggered when unsubscribing again while the group still doesn't exist. Originally, I had a warning in the subscribe case and accepted it out of userspace API concerns, but the warning was of course wrong and removed later. However, I now think that allowing userspace to subscribe to groups that don't exist is wrong and could possibly become a security problem: Consider a (new) genetlink family implementing a permission check in the mcast_bind() function similar to the like the audit code does today; it would be possible to bypass the permission check by guessing the ID and subscribing to the group it exists. This is only possible in case a family like that would be dynamically loaded, but it doesn't seem like a huge stretch, for example wireless may be loaded when you plug in a USB device. To avoid this reject such subscription attempts. If this ends up causing userspace issues we may need to add a workaround in af_netlink to deny such requests but not return an error. Reported-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-16netlink: Fix netlink_insert EADDRINUSE errorHerbert Xu1-4/+7
The patch c5adde9468b0714a051eac7f9666f23eb10b61f7 ("netlink: eliminate nl_sk_hash_lock") introduced a bug where the EADDRINUSE error has been replaced by ENOMEM. This patch rectifies that problem. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-13netlink: eliminate nl_sk_hash_lockYing Xue3-19/+25
As rhashtable_lookup_compare_insert() can guarantee the process of search and insertion is atomic, it's safe to eliminate the nl_sk_hash_lock. After this, object insertion or removal will be protected with per bucket lock on write side while object lookup is guarded with rcu read lock on read side. Signed-off-by: Ying Xue <ying.xue@windriver.com> Cc: Thomas Graf <tgraf@suug.ch> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-03netlink: Lockless lookup with RCU grace period in socket releaseThomas Graf2-16/+17
Defers the release of the socket reference using call_rcu() to allow using an RCU read-side protected call to rhashtable_lookup() This restores behaviour and performance gains as previously introduced by e341694 ("netlink: Convert netlink_lookup() to use RCU protected hash table") without the side effect of severely delayed socket destruction. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-03rhashtable: Per bucket locks & deferred expansion/shrinkingThomas Graf1-13/+2
Introduces an array of spinlocks to protect bucket mutations. The number of spinlocks per CPU is configurable and selected based on the hash of the bucket. This allows for parallel insertions and removals of entries which do not share a lock. The patch also defers expansion and shrinking to a worker queue which allows insertion and removal from atomic context. Insertions and deletions may occur in parallel to it and are only held up briefly while the particular bucket is linked or unzipped. Mutations of the bucket table pointer is protected by a new mutex, read access is RCU protected. In the event of an expansion or shrinking, the new bucket table allocated is exposed as a so called future table as soon as the resize process starts. Lookups, deletions, and insertions will briefly use both tables. The future table becomes the main table after an RCU grace period and initial linking of the old to the new table was performed. Optimization of the chains to make use of the new number of buckets follows only the new table is in use. The side effect of this is that during that RCU grace period, a bucket traversal using any rht_for_each() variant on the main table will not see any insertions performed during the RCU grace period which would at that point land in the future table. The lookup will see them as it searches both tables if needed. Having multiple insertions and removals occur in parallel requires nelems to become an atomic counter. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-03rhashtable: Convert bucket iterators to take table and indexThomas Graf2-5/+11
This patch is in preparation to introduce per bucket spinlocks. It extends all iterator macros to take the bucket table and bucket index. It also introduces a new rht_dereference_bucket() to handle protected accesses to buckets. It introduces a barrier() to the RCU iterators to the prevent the compiler from caching the first element. The lockdep verifier is introduced as stub which always succeeds and properly implement in the next patch when the locks are introduced. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-03rhashtable: Do hashing inside of rhashtable_lookup_compare()Thomas Graf1-4/+1
Hash the key inside of rhashtable_lookup_compare() like rhashtable_lookup() does. This allows to simplify the hashing functions and keep them private. Signed-off-by: Thomas Graf <tgraf@suug.ch> Cc: netfilter-devel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-29genetlink: A genl_bind() to an out-of-range multicast group should not WARN().David S. Miller1-6/+1
Users can request to bind to arbitrary multicast groups, so warning when the requested group number is out of range is not appropriate. And with the warning removed, and the 'err' variable properly given an initial value, we can remove 'found' altogether. Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-27netlink/genetlink: pass network namespace to bind/unbindJohannes Berg3-19/+22
Netlink families can exist in multiple namespaces, and for the most part multicast subscriptions are per network namespace. Thus it only makes sense to have bind/unbind notifications per network namespace. To achieve this, pass the network namespace of a given client socket to the bind/unbind functions. Also do this in generic netlink, and there also make sure that any bind for multicast groups that only exist in init_net is rejected. This isn't really a problem if it is accepted since a client in a different namespace will never receive any notifications from such a group, but it can confuse the family if not rejected (it's also possible to silently (without telling the family) accept it, but it would also have to be ignored on unbind so families that take any kind of action on bind/unbind won't do unnecessary work for invalid clients like that. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-27genetlink: pass multicast bind/unbind to familiesJohannes Berg1-0/+59
In order to make the newly fixed multicast bind/unbind functionality in generic netlink, pass them down to the appropriate family. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>

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