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2020-02-04proc: convert everything to "struct proc_ops"Alexey Dobriyan1-12/+12
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in seq_file.h. Conversion rule is: llseek => proc_lseek unlocked_ioctl => proc_ioctl xxx => proc_xxx delete ".owner = THIS_MODULE" line [akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c] [sfr@canb.auug.org.au: fix kernel/sched/psi.c] Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-0/+1
Minor conflict in mlx5 because changes happened to code that has moved meanwhile. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24rt_cpu_seq_next should increase position indexVasily Averin1-0/+1
if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-14ipv4: Add "offload" and "trap" indications to routesIdo Schimmel1-0/+19
When performing L3 offload, routes and nexthops are usually programmed into two different tables in the underlying device. Therefore, the fact that a nexthop resides in hardware does not necessarily mean that all the associated routes also reside in hardware and vice-versa. While the kernel can signal to user space the presence of a nexthop in hardware (via 'RTNH_F_OFFLOAD'), it does not have a corresponding flag for routes. In addition, the fact that a route resides in hardware does not necessarily mean that the traffic is offloaded. For example, unreachable routes (i.e., 'RTN_UNREACHABLE') are programmed to trap packets to the CPU so that the kernel will be able to generate the appropriate ICMP error packet. This patch adds an "offload" and "trap" indications to IPv4 routes, so that users will have better visibility into the offload process. 'struct fib_alias' is extended with two new fields that indicate if the route resides in hardware or not and if it is offloading traffic from the kernel or trapping packets to it. Note that the new fields are added in the 6 bytes hole and therefore the struct still fits in a single cache line [1]. Capable drivers are expected to invoke fib_alias_hw_flags_set() with the route's key in order to set the flags. The indications are dumped to user space via a new flags (i.e., 'RTM_F_OFFLOAD' and 'RTM_F_TRAP') in the 'rtm_flags' field in the ancillary header. v2: * Make use of 'struct fib_rt_info' in fib_alias_hw_flags_set() [1] struct fib_alias { struct hlist_node fa_list; /* 0 16 */ struct fib_info * fa_info; /* 16 8 */ u8 fa_tos; /* 24 1 */ u8 fa_type; /* 25 1 */ u8 fa_state; /* 26 1 */ u8 fa_slen; /* 27 1 */ u32 tb_id; /* 28 4 */ s16 fa_default; /* 32 2 */ u8 offload:1; /* 34: 0 1 */ u8 trap:1; /* 34: 1 1 */ u8 unused:6; /* 34: 2 1 */ /* XXX 5 bytes hole, try to pack */ struct callback_head rcu __attribute__((__aligned__(8))); /* 40 16 */ /* size: 56, cachelines: 1, members: 12 */ /* sum members: 50, holes: 1, sum holes: 5 */ /* sum bitfield members: 8 bits (1 bytes) */ /* forced alignments: 1, forced holes: 1, sum forced holes: 5 */ /* last cacheline: 56 bytes */ } __attribute__((__aligned__(8))); Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: David Ahern <dsahern@gmail.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-14ipv4: Encapsulate function arguments in a structIdo Schimmel1-3/+9
fib_dump_info() is used to prepare RTM_{NEW,DEL}ROUTE netlink messages using the passed arguments. Currently, the function takes 11 arguments, 6 of which are attributes of the route being dumped (e.g., prefix, TOS). The next patch will need the function to also dump to user space an indication if the route is present in hardware or not. Instead of passing yet another argument, change the function to take a struct containing the different route attributes. v2: * Name last argument of fib_dump_info() * Move 'struct fib_rt_info' to include/net/ip_fib.h so that it could later be passed to fib_alias_hw_flags_set() Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: David Ahern <dsahern@gmail.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-24net: add bool confirm_neigh parameter for dst_ops.update_pmtuHangbin Liu1-3/+6
The MTU update code is supposed to be invoked in response to real networking events that update the PMTU. In IPv6 PMTU update function __ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor confirmed time. But for tunnel code, it will call pmtu before xmit, like: - tnl_update_pmtu() - skb_dst_update_pmtu() - ip6_rt_update_pmtu() - __ip6_rt_update_pmtu() - dst_confirm_neigh() If the tunnel remote dst mac address changed and we still do the neigh confirm, we will not be able to update neigh cache and ping6 remote will failed. So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we should not be invoking dst_confirm_neigh() as we have no evidence of successful two-way communication at this point. On the other hand it is also important to keep the neigh reachability fresh for TCP flows, so we cannot remove this dst_confirm_neigh() call. To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu to choose whether we should do neigh update or not. I will add the parameter in this patch and set all the callers to true to comply with the previous way, and fix the tunnel code one by one on later patches. v5: No change. v4: No change. v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Suggested-by: David Miller <davem@davemloft.net> Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21ipv4: use dst hint for ipv4 list receivePaolo Abeni1-0/+42
This is alike the previous change, with some additional ipv4 specific quirk. Even when using the route hint we still have to do perform additional per packet checks about source address validity: a new helper is added to wrap them. Hints are explicitly disabled if the destination is a local broadcast, that keeps the code simple and local broadcast are a slower path anyway. UDP flood performances vs recvmmsg() receiver: vanilla patched delta Kpps Kpps % 1683 1871 +11 In the worst case scenario - each packet has a different destination address - the performance delta is within noise range. v3 -> v4: - re-enable hints for forward v2 -> v3: - really fix build (sic) and hint usage check - use fib4_has_custom_rules() helpers (David A.) - add ip_extract_route_hint() helper (Edward C.) - use prev skb as hint instead of copying data (Willem) v1 -> v2: - fix build issue with !CONFIG_IP_MULTIPLE_TABLES Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-05icmp: remove duplicate codeMatteo Croce1-4/+1
The same code which recognizes ICMP error packets is duplicated several times. Use the icmp_is_err() and icmpv6_is_err() helpers instead, which do the same thing. ip_multipath_l3_keys() and tcf_nat_act() didn't check for all the error types, assume that they should instead. Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17ipv4: fix race condition between route lookup and invalidationWei Wang1-1/+1
Jesse and Ido reported the following race condition: <CPU A, t0> - Received packet A is forwarded and cached dst entry is taken from the nexthop ('nhc->nhc_rth_input'). Calls skb_dst_set() <t1> - Given Jesse has busy routers ("ingesting full BGP routing tables from multiple ISPs"), route is added / deleted and rt_cache_flush() is called <CPU B, t2> - Received packet B tries to use the same cached dst entry from t0, but rt_cache_valid() is no longer true and it is replaced in rt_cache_route() by the newer one. This calls dst_dev_put() on the original dst entry which assigns the blackhole netdev to 'dst->dev' <CPU A, t3> - dst_input(skb) is called on packet A and it is dropped due to 'dst->dev' being the blackhole netdev There are 2 issues in the v4 routing code: 1. A per-netns counter is used to do the validation of the route. That means whenever a route is changed in the netns, users of all routes in the netns needs to redo lookup. v6 has an implementation of only updating fn_sernum for routes that are affected. 2. When rt_cache_valid() returns false, rt_cache_route() is called to throw away the current cache, and create a new one. This seems unnecessary because as long as this route does not change, the route cache does not need to be recreated. To fully solve the above 2 issues, it probably needs quite some code changes and requires careful testing, and does not suite for net branch. So this patch only tries to add the deleted cached rt into the uncached list, so user could still be able to use it to receive packets until it's done. Fixes: 95c47f9cf5e0 ("ipv4: call dst_dev_put() properly") Signed-off-by: Wei Wang <weiwan@google.com> Reported-by: Ido Schimmel <idosch@idosch.org> Reported-by: Jesse Hathaway <jesse@mbuki-mvuki.org> Tested-by: Jesse Hathaway <jesse@mbuki-mvuki.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Cc: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17ipv4: Return -ENETUNREACH if we can't create route but saddr is validStefano Brivio1-3/+6
...instead of -EINVAL. An issue was found with older kernel versions while unplugging a NFS client with pending RPCs, and the wrong error code here prevented it from recovering once link is back up with a configured address. Incidentally, this is not an issue anymore since commit 4f8943f80883 ("SUNRPC: Replace direct task wakeups from softirq context"), included in 5.2-rc7, had the effect of decoupling the forwarding of this error by using SO_ERROR in xs_wake_error(), as pointed out by Benjamin Coddington. To the best of my knowledge, this isn't currently causing any further issue, but the error code doesn't look appropriate anyway, and we might hit this in other paths as well. In detail, as analysed by Gonzalo Siero, once the route is deleted because the interface is down, and can't be resolved and we return -EINVAL here, this ends up, courtesy of inet_sk_rebuild_header(), as the socket error seen by tcp_write_err(), called by tcp_retransmit_timer(). In turn, tcp_write_err() indirectly calls xs_error_report(), which wakes up the RPC pending tasks with a status of -EINVAL. This is then seen by call_status() in the SUN RPC implementation, which aborts the RPC call calling rpc_exit(), instead of handling this as a potentially temporary condition, i.e. as a timeout. Return -EINVAL only if the input parameters passed to ip_route_output_key_hash_rcu() are actually invalid (this is the case if the specified source address is multicast, limited broadcast or all zeroes), but return -ENETUNREACH in all cases where, at the given moment, the given source address doesn't allow resolving the route. While at it, drop the initialisation of err to -ENETUNREACH, which was added to __ip_route_output_key() back then by commit 0315e3827048 ("net: Fix behaviour of unreachable, blackhole and prohibit routes"), but actually had no effect, as it was, and is, overwritten by the fib_lookup() return code assignment, and anyway ignored in all other branches, including the if (fl4->saddr) one: I find this rather confusing, as it would look like -ENETUNREACH is the "default" error, while that statement has no effect. Also note that after commit fc75fc8339e7 ("ipv4: dont create routes on down devices"), we would get -ENETUNREACH if the device is down, but -EINVAL if the source address is specified and we can't resolve the route, and this appears to be rather inconsistent. Reported-by: Stefan Walter <walteste@inf.ethz.ch> Analysed-by: Benjamin Coddington <bcodding@redhat.com> Analysed-by: Gonzalo Siero <gsierohu@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-04net: ipv4: avoid mixed n_redirects and rate_tokens usagePaolo Abeni1-3/+2
Since commit c09551c6ff7f ("net: ipv4: use a dedicated counter for icmp_v4 redirect packets") we use 'n_redirects' to account for redirect packets, but we still use 'rate_tokens' to compute the redirect packets exponential backoff. If the device sent to the relevant peer any ICMP error packet after sending a redirect, it will also update 'rate_token' according to the leaking bucket schema; typically 'rate_token' will raise above BITS_PER_LONG and the redirect packets backoff algorithm will produce undefined behavior. Fix the issue using 'n_redirects' to compute the exponential backoff in ip_rt_send_redirect(). Note that we still clear rate_tokens after a redirect silence period, to avoid changing an established behaviour. The root cause predates git history; before the mentioned commit in the critical scenario, the kernel stopped sending redirects, after the mentioned commit the behavior more randomic. Reported-by: Xiumei Mu <xmu@redhat.com> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Fixes: c09551c6ff7f ("net: ipv4: use a dedicated counter for icmp_v4 redirect packets") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-20ipv4: Revert removal of rt_uses_gatewayDavid Ahern1-15/+21
Julian noted that rt_uses_gateway has a more subtle use than 'is gateway set': https://lore.kernel.org/netdev/alpine.LFD.2.21.1909151104060.2546@ja.home.ssi.bg/ Revert that part of the commit referenced in the Fixes tag. Currently, there are no u8 holes in 'struct rtable'. There is a 4-byte hole in the second cacheline which contains the gateway declaration. So move rt_gw_family down to the gateway declarations since they are always used together, and then re-use that u8 for rt_uses_gateway. End result is that rtable size is unchanged. Fixes: 1550c171935d ("ipv4: Prepare rtable for IPv6 gateway") Reported-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-08-24net: route dump netlink NLM_F_MULTI flag missingJohn Fastabend1-7/+10
An excerpt from netlink(7) man page, In multipart messages (multiple nlmsghdr headers with associated payload in one byte stream) the first and all following headers have the NLM_F_MULTI flag set, except for the last header which has the type NLMSG_DONE. but, after (ee28906) there is a missing NLM_F_MULTI flag in the middle of a FIB dump. The result is user space applications following above man page excerpt may get confused and may stop parsing msg believing something went wrong. In the golang netlink lib [0] the library logic stops parsing believing the message is not a multipart message. Found this running Cilium[1] against net-next while adding a feature to auto-detect routes. I noticed with multiple route tables we no longer could detect the default routes on net tree kernels because the library logic was not returning them. Fix this by handling the fib_dump_info_fnhe() case the same way the fib_dump_info() handles it by passing the flags argument through the call chain and adding a flags argument to rt_fill_info(). Tested with Cilium stack and auto-detection of routes works again. Also annotated libs to dump netlink msgs and inspected NLM_F_MULTI and NLMSG_DONE flags look correct after this. Note: In inet_rtm_getroute() pass rt_fill_info() '0' for flags the same as is done for fib_dump_info() so this looks correct to me. [0] https://github.com/vishvananda/netlink/ [1] https://github.com/cilium/ Fixes: ee28906fd7a14 ("ipv4: Dump route exceptions if requested") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Two cases of overlapping changes, nothing fancy. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-08ipv4: Multipath hashing on inner L3 needs to consider inner IPv6 pktsStephen Suryaputra1-4/+17
Commit 363887a2cdfe ("ipv4: Support multipath hashing on inner IP pkts for GRE tunnel") supports multipath policy value of 2, Layer 3 or inner Layer 3 if present, but it only considers inner IPv4. There is a use case of IPv6 is tunneled by IPv4 GRE, thus add the ability to hash on inner IPv6 addresses. Fixes: 363887a2cdfe ("ipv4: Support multipath hashing on inner IP pkts for GRE tunnel") Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-05ipv4: Fix NULL pointer dereference in ipv4_neigh_lookup()Ido Schimmel1-1/+1
Both ip_neigh_gw4() and ip_neigh_gw6() can return either a valid pointer or an error pointer, but the code currently checks that the pointer is not NULL. Fix this by checking that the pointer is not an error pointer, as this can result in a NULL pointer dereference [1]. Specifically, I believe that what happened is that ip_neigh_gw4() returned '-EINVAL' (0xffffffffffffffea) to which the offset of 'refcnt' (0x70) was added, which resulted in the address 0x000000000000005a. [1] BUG: KASAN: null-ptr-deref in refcount_inc_not_zero_checked+0x6e/0x180 Read of size 4 at addr 000000000000005a by task swapper/2/0 CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.2.0-rc6-custom-reg-179657-gaa32d89 #396 Hardware name: Mellanox Technologies Ltd. MSN2010/SA002610, BIOS 5.6.5 08/24/2017 Call Trace: <IRQ> dump_stack+0x73/0xbb __kasan_report+0x188/0x1ea kasan_report+0xe/0x20 refcount_inc_not_zero_checked+0x6e/0x180 ipv4_neigh_lookup+0x365/0x12c0 __neigh_update+0x1467/0x22f0 arp_process.constprop.6+0x82e/0x1f00 __netif_receive_skb_one_core+0xee/0x170 process_backlog+0xe3/0x640 net_rx_action+0x755/0xd90 __do_softirq+0x29b/0xae7 irq_exit+0x177/0x1c0 smp_apic_timer_interrupt+0x164/0x5e0 apic_timer_interrupt+0xf/0x20 </IRQ> Fixes: 5c9f7c1dfc2e ("ipv4: Add helpers for neigh lookup for nexthop") Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reported-by: Shalom Toledo <shalomt@mellanox.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-01blackhole_netdev: use blackhole_netdev to invalidate dst entriesMahesh Bandewar1-2/+1
Use blackhole_netdev instead of 'lo' device with lower MTU when marking dst "dead". Signed-off-by: Mahesh Bandewar <maheshb@google.com> Tested-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-28ipv4: enable route flushing in network namespacesChristian Brauner1-4/+8
Tools such as vpnc try to flush routes when run inside network namespaces by writing 1 into /proc/sys/net/ipv4/route/flush. This currently does not work because flush is not enabled in non-initial network namespaces. Since routes are per network namespace it is safe to enable /proc/sys/net/ipv4/route/flush in there. Link: https://github.com/lxc/lxd/issues/4257 Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+33
The new route handling in ip_mc_finish_output() from 'net' overlapped with the new support for returning congestion notifications from BPF programs. In order to handle this I had to take the dev_loopback_xmit() calls out of the switch statement. The aquantia driver conflicts were simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-26ipv4: reset rt_iif for recirculated mcast/bcast out pktsStephen Suryaputra1-0/+33
Multicast or broadcast egress packets have rt_iif set to the oif. These packets might be recirculated back as input and lookup to the raw sockets may fail because they are bound to the incoming interface (skb_iif). If rt_iif is not zero, during the lookup, inet_iif() function returns rt_iif instead of skb_iif. Hence, the lookup fails. v2: Make it non vrf specific (David Ahern). Reword the changelog to reflect it. Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-26ipv4: fix suspicious RCU usage in fib_dump_info_fnhe()Eric Dumazet1-5/+6
sysbot reported that we lack appropriate rcu_read_lock() protection in fib_dump_info_fnhe() net/ipv4/route.c:2875 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by syz-executor609/8966: #0: 00000000b7dbe288 (rtnl_mutex){+.+.}, at: netlink_dump+0xe7/0xfb0 net/netlink/af_netlink.c:2199 stack backtrace: CPU: 0 PID: 8966 Comm: syz-executor609 Not tainted 5.2.0-rc5+ #43 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5250 fib_dump_info_fnhe+0x9d9/0x1080 net/ipv4/route.c:2875 fn_trie_dump_leaf net/ipv4/fib_trie.c:2141 [inline] fib_table_dump+0x64a/0xd00 net/ipv4/fib_trie.c:2175 inet_dump_fib+0x83c/0xa90 net/ipv4/fib_frontend.c:1004 rtnl_dump_all+0x295/0x490 net/core/rtnetlink.c:3445 netlink_dump+0x558/0xfb0 net/netlink/af_netlink.c:2244 __netlink_dump_start+0x5b1/0x7d0 net/netlink/af_netlink.c:2352 netlink_dump_start include/linux/netlink.h:226 [inline] rtnetlink_rcv_msg+0x73d/0xb00 net/core/rtnetlink.c:5182 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5237 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:665 sock_write_iter+0x27c/0x3e0 net/socket.c:994 call_write_iter include/linux/fs.h:1872 [inline] new_sync_write+0x4d3/0x770 fs/read_write.c:483 __vfs_write+0xe1/0x110 fs/read_write.c:496 vfs_write+0x20c/0x580 fs/read_write.c:558 ksys_write+0x14f/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4401b9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc8e134978 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401b9 RDX: 000000000000001c RSI: 0000000020000000 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 0000000000000010 R11: 0000000000000246 R12: 0000000000401a40 R13: 0000000000401ad0 R14: 0000000000000000 R15: 0000000000000000 Fixes: ee28906fd7a1 ("ipv4: Dump route exceptions if requested") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: David Ahern <dsahern@gmail.com> Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-24ipv4: Dump route exceptions if requestedStefano Brivio1-0/+73
Since commit 4895c771c7f0 ("ipv4: Add FIB nexthop exceptions."), cached exception routes are stored as a separate entity, so they are not dumped on a FIB dump, even if the RTM_F_CLONED flag is passed. This implies that the command 'ip route list cache' doesn't return any result anymore. If the RTM_F_CLONED is passed, and strict checking requested, retrieve nexthop exception routes and dump them. If no strict checking is requested, filtering can't be performed consistently: dump everything in that case. With this, we need to add an argument to the netlink callback in order to track how many entries were already dumped for the last leaf included in a partial netlink dump. A single additional argument is sufficient, even if we traverse logically nested structures (nexthop objects, hash table buckets, bucket chains): it doesn't matter if we stop in the middle of any of those, because they are always traversed the same way. As an example, s_i values in [], s_fa values in (): node (fa) #1 [1] nexthop #1 bucket #1 -> #0 in chain (1) bucket #2 -> #0 in chain (2) -> #1 in chain (3) -> #2 in chain (4) bucket #3 -> #0 in chain (5) -> #1 in chain (6) nexthop #2 bucket #1 -> #0 in chain (7) -> #1 in chain (8) bucket #2 -> #0 in chain (9) -- node (fa) #2 [2] nexthop #1 bucket #1 -> #0 in chain (1) -> #1 in chain (2) bucket #2 -> #0 in chain (3) it doesn't matter if we stop at (3), (4), (7) for "node #1", or at (2) for "node #2": walking flattens all that. It would even be possible to drop the distinction between the in-tree (s_i) and in-node (s_fa) counter, but a further improvement might advise against this. This is only as accurate as the existing tracking mechanism for leaves: if a partial dump is restarted after exceptions are removed or expired, we might skip some non-dumped entries. To improve this, we could attach a 'sernum' attribute (similar to the one used for IPv6) to nexthop entities, and bump this counter whenever exceptions change: having a distinction between the two counters would make this more convenient. Listing of exception routes (modified routes pre-3.5) was tested against these versions of kernel and iproute2: iproute2 kernel 4.14.0 4.15.0 4.19.0 5.0.0 5.1.0 3.5-rc4 + + + + + 4.4 4.9 4.14 4.15 4.19 5.0 5.1 fixed + + + + + v7: - Move loop over nexthop objects to route.c, and pass struct fib_info and table ID to it, not a struct fib_alias (suggested by David Ahern) - While at it, note that the NULL check on fa->fa_info is redundant, and the check on RTNH_F_DEAD is also not consistent with what's done with regular route listing: just keep it for nhc_flags - Rename entry point function for dumping exceptions to fib_dump_info_fnhe(), and rearrange arguments for consistency with fib_dump_info() - Rename fnhe_dump_buckets() to fnhe_dump_bucket() and make it handle one bucket at a time - Expand commit message to describe why we can have a single "skip" counter for all exceptions stored in bucket chains in nexthop objects (suggested by David Ahern) v6: - Rebased onto net-next - Loop over nexthop paths too. Move loop over fnhe buckets to route.c, avoids need to export rt_fill_info() and to touch exceptions from fib_trie.c. Pass NULL as flow to rt_fill_info(), it now allows that (suggested by David Ahern) Fixes: 4895c771c7f0 ("ipv4: Add FIB nexthop exceptions.") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-24ipv4/route: Allow NULL flowinfo in rt_fill_info()Stefano Brivio1-26/+30
In the next patch, we're going to use rt_fill_info() to dump exception routes upon RTM_GETROUTE with NLM_F_ROOT, meaning userspace is requesting a dump and not a specific route selection, which in turn implies the input interface is not relevant. Update rt_fill_info() to handle a NULL flowinfo. v7: If fl4 is NULL, explicitly set r->rtm_tos to 0: it's not initialised otherwise (spotted by David Ahern) v6: New patch Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-14ipv4: Support multipath hashing on inner IP pkts for GRE tunnelStephen Suryaputra1-0/+17
Multipath hash policy value of 0 isn't distributing since the outer IP dest and src aren't varied eventhough the inner ones are. Since the flow is on the inner ones in the case of tunneled traffic, hashing on them is desired. This is done mainly for IP over GRE, hence only tested for that. But anything else supported by flow dissection should work. v2: Use skb_flow_dissect_flow_keys() directly so that other tunneling can be supported through flow dissection (per Nikolay Aleksandrov). v3: Remove accidental inclusion of ports in the hash keys and clarify the documentation (Nikolay Alexandrov). Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-17/+13
Some ISDN files that got removed in net-next had some changes done in mainline, take the removals. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds1-12/+12
Pull networking fixes from David Miller: 1) Free AF_PACKET po->rollover properly, from Willem de Bruijn. 2) Read SFP eeprom in max 16 byte increments to avoid problems with some SFP modules, from Russell King. 3) Fix UDP socket lookup wrt. VRF, from Tim Beale. 4) Handle route invalidation properly in s390 qeth driver, from Julian Wiedmann. 5) Memory leak on unload in RDS, from Zhu Yanjun. 6) sctp_process_init leak, from Neil HOrman. 7) Fix fib_rules rule insertion semantic change that broke Android, from Hangbin Liu. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (33 commits) pktgen: do not sleep with the thread lock held. net: mvpp2: Use strscpy to handle stat strings net: rds: fix memory leak in rds_ib_flush_mr_pool ipv6: fix EFAULT on sendto with icmpv6 and hdrincl ipv6: use READ_ONCE() for inet->hdrincl as in ipv4 Revert "fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied" net: aquantia: fix wol configuration not applied sometimes ethtool: fix potential userspace buffer overflow Fix memory leak in sctp_process_init net: rds: fix memory leak when unload rds_rdma ipv6: fix the check before getting the cookie in rt6_get_cookie ipv4: not do cache for local delivery if bc_forwarding is enabled s390/qeth: handle error when updating TX queue count s390/qeth: fix VLAN attribute in bridge_hostnotify udev event s390/qeth: check dst entry before use s390/qeth: handle limited IPv4 broadcast in L3 TX path net: fix indirect calls helpers for ptype list hooks. net: ipvlan: Fix ipvlan device tso disabled while NETIF_F_IP_CSUM is set udp: only choose unbound UDP socket for multicast when not in a VRF net/tls: replace the sleeping lock around RX resync with a bit lock ...
2019-06-05ipv4: not do cache for local delivery if bc_forwarding is enabledXin Long1-12/+12
With the topo: h1 ---| rp1 | | route rp3 |--- h3 (192.168.200.1) h2 ---| rp2 | If rp1 bc_forwarding is set while rp2 bc_forwarding is not, after doing "ping 192.168.200.255" on h1, then ping 192.168.200.255 on h2, and the packets can still be forwared. This issue was caused by the input route cache. It should only do the cache for either bc forwarding or local delivery. Otherwise, local delivery can use the route cache for bc forwarding of other interfaces. This patch is to fix it by not doing cache for local delivery if all.bc_forwarding is enabled. Note that we don't fix it by checking route cache local flag after rt_cache_valid() in "local_input:" and "ip_mkroute_input", as the common route code shouldn't be touched for bc_forwarding. Fixes: 5cbf777cfdf6 ("route: add support for directed broadcast forwarding") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-04ipv4: Prepare for fib6_nh from a nexthop objectDavid Ahern1-1/+1
Convert more IPv4 code to use fib_nh_common over fib_nh to enable routes to use a fib6_nh based nexthop. In the end, only code not using a nexthop object in a fib_info should directly access fib_nh in a fib_info without checking the famiy and going through fib_nh_common. Those functions will be marked when it is not directly evident. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-04ipv4: Use accessors for fib_info nexthop dataDavid Ahern1-1/+2
Use helpers to access fib_nh and fib_nhs fields of a fib_info. Drop the fib_dev macro which is an alias for the first nexthop. Replacements: fi->fib_dev --> fib_info_nh(fi, 0)->fib_nh_dev fi->fib_nh --> fib_info_nh(fi, 0) fi->fib_nh[i] --> fib_info_nh(fi, i) fi->fib_nhs --> fib_info_num_path(fi) where fib_info_nh(fi, i) returns fi->fib_nh[nhsel] and fib_info_num_path returns fi->fib_nhs. Move the existing fib_info_nhc to nexthop.h and define the new ones there. A later patch adds a check if a fib_info uses a nexthop object, and defining the helpers in nexthop.h avoid circular header dependencies. After this all remaining open coded references to fi->fib_nhs and fi->fib_nh are in: - fib_create_info and helpers used to lookup an existing fib_info entry, and - the netdev event functions fib_sync_down_dev and fib_sync_up. The latter two will not be reused for nexthops, and the fib_create_info will be updated to handle a nexthop in a fib_info. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-5/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-05ipv4: Move exception bucket to nh_commonDavid Ahern1-24/+17
Similar to the cached routes, make IPv4 exceptions accessible when using an IPv6 nexthop struct with IPv4 routes. Simplify the exception functions by passing in fib_nh_common since that is all it needs, and then cleanup the call sites that have extraneous fib_nh conversions. As with the cached routes this is a change in location only, from fib_nh up to fib_nh_common; no functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05ipv4: Pass fib_nh_common to rt_cache_routeDavid Ahern1-10/+10
Now that the cached routes are in fib_nh_common, pass it to rt_cache_route and simplify its callers. For rt_set_nexthop, the tclassid becomes the last user of fib_nh so move the container_of under the #ifdef CONFIG_IP_ROUTE_CLASSID. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05ipv4: Move cached routes to fib_nh_commonDavid Ahern1-9/+9
While the cached routes, nh_pcpu_rth_output and nh_rth_input, are IPv4 specific, a later patch wants to make them accessible for IPv6 nexthops with IPv4 routes using a fib6_nh. Move the cached routes from fib_nh to fib_nh_common and update references. Initialization of the cached entries is moved to fib_nh_common_init, and free is moved to fib_nh_common_release. Change in location only, from fib_nh up to fib_nh_common; no functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27netlink: make validation more configurable for future strictnessJohannes Berg1-4/+4
We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-9/+23
Two easy cases of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-24ipv4: add sanity checks in ipv4_link_failure()Eric Dumazet1-9/+23
Before calling __ip_options_compile(), we need to ensure the network header is a an IPv4 one, and that it is already pulled in skb->head. RAW sockets going through a tunnel can end up calling ipv4_link_failure() with total garbage in the skb, or arbitrary lengthes. syzbot report : BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:355 [inline] BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0x294/0x1120 net/ipv4/ip_options.c:123 Write of size 69 at addr ffff888096abf068 by task syz-executor.4/9204 CPU: 0 PID: 9204 Comm: syz-executor.4 Not tainted 5.1.0-rc5+ #77 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 memcpy+0x38/0x50 mm/kasan/common.c:133 memcpy include/linux/string.h:355 [inline] __ip_options_echo+0x294/0x1120 net/ipv4/ip_options.c:123 __icmp_send+0x725/0x1400 net/ipv4/icmp.c:695 ipv4_link_failure+0x29f/0x550 net/ipv4/route.c:1204 dst_link_failure include/net/dst.h:427 [inline] vti6_xmit net/ipv6/ip6_vti.c:514 [inline] vti6_tnl_xmit+0x10d4/0x1c0c net/ipv6/ip6_vti.c:553 __netdev_start_xmit include/linux/netdevice.h:4414 [inline] netdev_start_xmit include/linux/netdevice.h:4423 [inline] xmit_one net/core/dev.c:3292 [inline] dev_hard_start_xmit+0x1b2/0x980 net/core/dev.c:3308 __dev_queue_xmit+0x271d/0x3060 net/core/dev.c:3878 dev_queue_xmit+0x18/0x20 net/core/dev.c:3911 neigh_direct_output+0x16/0x20 net/core/neighbour.c:1527 neigh_output include/net/neighbour.h:508 [inline] ip_finish_output2+0x949/0x1740 net/ipv4/ip_output.c:229 ip_finish_output+0x73c/0xd50 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_output+0x21f/0x670 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] raw_send_hdrinc net/ipv4/raw.c:432 [inline] raw_sendmsg+0x1d2b/0x2f20 net/ipv4/raw.c:663 inet_sendmsg+0x147/0x5d0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:661 sock_write_iter+0x27c/0x3e0 net/socket.c:988 call_write_iter include/linux/fs.h:1866 [inline] new_sync_write+0x4c7/0x760 fs/read_write.c:474 __vfs_write+0xe4/0x110 fs/read_write.c:487 vfs_write+0x20c/0x580 fs/read_write.c:549 ksys_write+0x14f/0x2d0 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:608 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f293b44bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29 RDX: 0000000000000014 RSI: 00000000200002c0 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f293b44c6d4 R13: 00000000004c8623 R14: 00000000004ded68 R15: 00000000ffffffff The buggy address belongs to the page: page:ffffea00025aafc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x1fffc0000000000() raw: 01fffc0000000000 0000000000000000 ffffffff025a0101 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888096abef80: 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 f2 ffff888096abf000: f2 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888096abf080: 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 ^ ffff888096abf100: 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 00 00 00 00 ffff888096abf180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Fixes: ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stephen Suryaputra <ssuryaextr@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+15
Conflict resolution of af_smc.c from Stephen Rothwell. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-14ipv4: ensure rcu_read_lock() in ipv4_link_failure()Eric Dumazet1-2/+8
fib_compute_spec_dst() needs to be called under rcu protection. syzbot reported : WARNING: suspicious RCU usage 5.1.0-rc4+ #165 Not tainted include/linux/inetdevice.h:220 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by swapper/0/0: #0: 0000000051b67925 ((&n->timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:170 [inline] #0: 0000000051b67925 ((&n->timer)){+.-.}, at: call_timer_fn+0xda/0x720 kernel/time/timer.c:1315 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.1.0-rc4+ #165 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5162 __in_dev_get_rcu include/linux/inetdevice.h:220 [inline] fib_compute_spec_dst+0xbbd/0x1030 net/ipv4/fib_frontend.c:294 spec_dst_fill net/ipv4/ip_options.c:245 [inline] __ip_options_compile+0x15a7/0x1a10 net/ipv4/ip_options.c:343 ipv4_link_failure+0x172/0x400 net/ipv4/route.c:1195 dst_link_failure include/net/dst.h:427 [inline] arp_error_report+0xd1/0x1c0 net/ipv4/arp.c:297 neigh_invalidate+0x24b/0x570 net/core/neighbour.c:995 neigh_timer_handler+0xc35/0xf30 net/core/neighbour.c:1081 call_timer_fn+0x190/0x720 kernel/time/timer.c:1325 expire_timers kernel/time/timer.c:1362 [inline] __run_timers kernel/time/timer.c:1681 [inline] __run_timers kernel/time/timer.c:1649 [inline] run_timer_softirq+0x652/0x1700 kernel/time/timer.c:1694 __do_softirq+0x266/0x95a kernel/softirq.c:293 invoke_softirq kernel/softirq.c:374 [inline] irq_exit+0x180/0x1d0 kernel/softirq.c:414 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x14a/0x570 arch/x86/kernel/apic/apic.c:1062 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807 Fixes: ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-12ipv4: recompile ip options in ipv4_link_failureStephen Suryaputra1-1/+9
Recompile IP options since IPCB may not be valid anymore when ipv4_link_failure is called from arp_error_report. Refer to the commit 3da1ed7ac398 ("net: avoid use IPCB in cipso_v4_error") and the commit before that (9ef6b42ad6fd) for a similar issue. Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-08ipv4: Handle ipv6 gateway in ipv4_confirm_neighDavid Ahern1-4/+6
Update ipv4_confirm_neigh to handle an ipv6 gateway. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-08ipv4: Add helpers for neigh lookup for nexthopDavid Ahern1-10/+19
A common theme in the output path is looking up a neigh entry for a nexthop, either the gateway in an rtable or a fallback to the daddr in the skb: nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr); neigh = __ipv4_neigh_lookup_noref(dev, nexthop); if (unlikely(!neigh)) neigh = __neigh_create(&arp_tbl, &nexthop, dev, false); To allow the nexthop to be an IPv6 address we need to consider the family of the nexthop and then call __ipv{4,6}_neigh_lookup_noref based on it. To make this simpler, add a ip_neigh_gw4 helper similar to ip_neigh_gw6 added in an earlier patch which handles: neigh = __ipv4_neigh_lookup_noref(dev, nexthop); if (unlikely(!neigh)) neigh = __neigh_create(&arp_tbl, &nexthop, dev, false); And then add a second one, ip_neigh_for_gw, that calls either ip_neigh_gw4 or ip_neigh_gw6 based on the address family of the gateway. Update the output paths in the VRF driver and core v4 code to use ip_neigh_for_gw simplifying the family based lookup and making both ready for a v6 nexthop. ipv4_neigh_lookup has a different need - the potential to resolve a passed in address in addition to any gateway in the rtable or skb. Since this is a one-off, add ip_neigh_gw4 and ip_neigh_gw6 diectly. The difference between __neigh_create used by the helpers and neigh_create called by ipv4_neigh_lookup is taking a refcount, so add rcu_read_lock_bh and bump the refcnt on the neigh entry. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-08ipv4: Add support to rtable for ipv6 gatewayDavid Ahern1-5/+26
Add support for an IPv6 gateway to rtable. Since a gateway is either IPv4 or IPv6, make it a union with rt_gw4 where rt_gw_family decides which address is in use. When dumping the route data, encode an ipv6 nexthop using RTA_VIA. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-08ipv4: Prepare rtable for IPv6 gatewayDavid Ahern1-24/+27
To allow the gateway to be either an IPv4 or IPv6 address, remove rt_uses_gateway from rtable and replace with rt_gw_family. If rt_gw_family is set it implies rt_uses_gateway. Rename rt_gateway to rt_gw4 to represent the IPv4 version. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-08net: Replace nhc_has_gw with nhc_gw_familyDavid Ahern1-2/+3
Allow the gateway in a fib_nh_common to be from a different address family than the outer fib{6}_nh. To that end, replace nhc_has_gw with nhc_gw_family and update users of nhc_has_gw to check nhc_gw_family. Now nhc_family is used to know if the nh_common is part of a fib_nh or fib6_nh (used for container_of to get to route family specific data), and nhc_gw_family represents the address family for the gateway. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-03ipv4: Add fib_nh_common to fib_resultDavid Ahern1-20/+40
Most of the ipv4 code only needs data from fib_nh_common. Add fib_nh_common selection to fib_result and update users to use it. Right now, fib_nh_common in fib_result will point to a fib_nh struct that is embedded within a fib_info: fib_info --> fib_nh fib_nh ... fib_nh ^ fib_result->nhc ----+ Later, nhc can point to a fib_nh within a nexthop struct: fib_info --> nexthop --> fib_nh ^ fib_result->nhc ---------------+ or for a nexthop group: fib_info --> nexthop --> nexthop --> fib_nh nexthop --> fib_nh ... nexthop --> fib_nh ^ fib_result->nhc ---------------------------+ In all cases nhsel within fib_result will point to which leg in the multipath route is used. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-29ipv4: Rename fib_nh entriesDavid Ahern1-9/+9
Rename fib_nh entries that will be moved to a fib_nh_common struct. Specifically, the device, oif, gateway, flags, scope, lwtstate, nh_weight and nh_upper_bound are common with all nexthop definitions. In the process shorten fib_nh_lwtstate to fib_nh_lws to avoid really long lines. Rename only; no functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-27inet: switch IP ID generator to siphashEric Dumazet1-5/+7
According to Amit Klein and Benny Pinkas, IP ID generation is too weak and might be used by attackers. Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix()) having 64bit key and Jenkins hash is risky. It is time to switch to siphash and its 128bit keys. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-21net: dst: remove gc leftoversJulian Wiedmann1-1/+1
Get rid of some obsolete gc-related documentation and macros that were missed in commit 5b7c9a8ff828 ("net: remove dst gc related code"). CC: Wei Wang <weiwan@google.com> Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-08route: set the deleted fnhe fnhe_daddr to 0 in ip_del_fnhe to fix a raceXin Long1-0/+4
The race occurs in __mkroute_output() when 2 threads lookup a dst: CPU A CPU B find_exception() find_exception() [fnhe expires] ip_del_fnhe() [fnhe is deleted] rt_bind_exception() In rt_bind_exception() it will bind a deleted fnhe with the new dst, and this dst will get no chance to be freed. It causes a dev defcnt leak and consecutive dmesg warnings: unregister_netdevice: waiting for ethX to become free. Usage count = 1 Especially thanks Jon to identify the issue. This patch fixes it by setting fnhe_daddr to 0 in ip_del_fnhe() to stop binding the deleted fnhe with a new dst when checking fnhe's fnhe_daddr and daddr in rt_bind_exception(). It works as both ip_del_fnhe() and rt_bind_exception() are protected by fnhe_lock and the fhne is freed by kfree_rcu(). Fixes: deed49df7390 ("route: check and remove route cache when we get route") Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-06ipv4/route: fail early when inet dev is missingPaolo Abeni1-4/+5
If a non local multicast packet reaches ip_route_input_rcu() while the ingress device IPv4 private data (in_dev) is NULL, we end up doing a NULL pointer dereference in IN_DEV_MFORWARD(). Since the later call to ip_route_input_mc() is going to fail if !in_dev, we can fail early in such scenario and avoid the dangerous code path. v1 -> v2: - clarified the commit message, no code changes Reported-by: Tianhao Zhao <tizhao@redhat.com> Fixes: e58e41596811 ("net: Enable support for VRF with ipv4 multicast") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>