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2018-05-16proc: introduce proc_create_net{,_data}Christoph Hellwig1-15/+2
Variants of proc_create{,_data} that directly take a struct seq_operations and deal with network namespaces in ->open and ->release. All callers of proc_create + seq_open_net converted over, and seq_{open,release}_net are removed entirely. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-03-27net: Drop pernet_operations::asyncKirill Tkhai1-1/+0
Synchronous pernet_operations are not allowed anymore. All are asynchronous. So, drop the structure member. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-26net: Use octal not symbolic permissionsJoe Perches1-1/+1
Prefer the direct use of octal for permissions. Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace and some typing. Miscellanea: o Whitespace neatening around these conversions. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-27net: Convert synproxy_net_opsKirill Tkhai1-0/+1
These pernet_operations create and destroy /proc entries and allocate extents to template ct, which depend on global nf_ct_ext_types[] array. So, we are able to mark them async. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19netfilter: delete /proc THIS_MODULE referencesAlexey Dobriyan1-1/+0
/proc has been ignoring struct file_operations::owner field for 10 years. Specifically, it started with commit 786d7e1612f0b0adb6046f19b906609e4fe8b1ba ("Fix rmmod/read/write races in /proc entries"). Notice the chunk where inode->i_fop is initialized with proxy struct file_operations for regular files: - if (de->proc_fops) - inode->i_fop = de->proc_fops; + if (de->proc_fops) { + if (S_ISREG(inode->i_mode)) + inode->i_fop = &proc_reg_file_ops; + else + inode->i_fop = de->proc_fops; + } VFS stopped pinning module at this point. # ipvs Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-17tcp: switch TCP TS option (RFC 7323) to 1ms clockEric Dumazet1-1/+1
TCP Timestamps option is defined in RFC 7323 Traditionally on linux, it has been tied to the internal 'jiffies' variable, because it had been a cheap and good enough generator. For TCP flows on the Internet, 1 ms resolution would be much better than 4ms or 10ms (HZ=250 or HZ=100 respectively) For TCP flows in the DC, Google has used usec resolution for more than two years with great success [1] Receive size autotuning (DRS) is indeed more precise and converges faster to optimal window size. This patch converts tp->tcp_mstamp to a plain u64 value storing a 1 usec TCP clock. This choice will allow us to upstream the 1 usec TS option as discussed in IETF 97. [1] https://www.ietf.org/proceedings/97/slides/slides-97-tcpm-tcp-options-for-low-latency-00.pdf Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-19netfilter: tcp: Use TCP_MAX_WSCALE instead of literal 14Gao Feng1-2/+2
The window scale may be enlarged from 14 to 15 according to the itef draft https://tools.ietf.org/html/draft-nishida-tcpm-maxwin-03. Use the macro TCP_MAX_WSCALE to support it easily with TCP stack in the future. Signed-off-by: Gao Feng <fgao@ikuai8.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-07netfilter: Use seq_puts()/seq_putc() where possiblesimran singhal1-3/+3
For string without format specifiers, use seq_puts(). For seq_printf("\n"), use seq_putc('\n'). Signed-off-by: simran singhal <singhalsimran0@gmail.com> Acked-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-18netns: make struct pernet_operations::id unsigned intAlexey Dobriyan1-1/+1
Make struct pernet_operations::id unsigned. There are 2 reasons to do so: 1) This field is really an index into an zero based array and thus is unsigned entity. Using negative value is out-of-bound access by definition. 2) On x86_64 unsigned 32-bit data which are mixed with pointers via array indexing or offsets added or subtracted to pointers are preffered to signed 32-bit data. "int" being used as an array index needs to be sign-extended to 64-bit before being used. void f(long *p, int i) { g(p[i]); } roughly translates to movsx rsi, esi mov rdi, [rsi+...] call g MOVSX is 3 byte instruction which isn't necessary if the variable is unsigned because x86_64 is zero extending by default. Now, there is net_generic() function which, you guessed it right, uses "int" as an array index: static inline void *net_generic(const struct net *net, int id) { ... ptr = ng->ptr[id - 1]; ... } And this function is used a lot, so those sign extensions add up. Patch snipes ~1730 bytes on allyesconfig kernel (without all junk messing with code generation): add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) Unfortunately some functions actually grow bigger. This is a semmingly random artefact of code generation with register allocator being used differently. gcc decides that some variable needs to live in new r8+ registers and every access now requires REX prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be used which is longer than [r8] However, overall balance is in negative direction: add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) function old new delta nfsd4_lock 3886 3959 +73 tipc_link_build_proto_msg 1096 1140 +44 mac80211_hwsim_new_radio 2776 2808 +32 tipc_mon_rcv 1032 1058 +26 svcauth_gss_legacy_init 1413 1429 +16 tipc_bcbase_select_primary 379 392 +13 nfsd4_exchange_id 1247 1260 +13 nfsd4_setclientid_confirm 782 793 +11 ... put_client_renew_locked 494 480 -14 ip_set_sockfn_get 730 716 -14 geneve_sock_add 829 813 -16 nfsd4_sequence_done 721 703 -18 nlmclnt_lookup_host 708 686 -22 nfsd4_lockt 1085 1063 -22 nfs_get_client 1077 1050 -27 tcf_bpf_init 1106 1076 -30 nfsd4_encode_fattr 5997 5930 -67 Total: Before=154856051, After=154854321, chg -0.00% Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller1-1/+1
Conflicts: include/net/netfilter/nf_conntrack.h The conflict was an overlap between changing the type of the zone argument to nf_ct_tmpl_alloc() whilst exporting nf_ct_tmpl_free. Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net, they are: 1) Oneliner to restore maps in nf_tables since we support addressing registers at 32 bits level. 2) Restore previous default behaviour in bridge netfilter when CONFIG_IPV6=n, oneliner from Bernhard Thaler. 3) Out of bound access in ipset hash:net* set types, reported by Dave Jones' KASan utility, patch from Jozsef Kadlecsik. 4) Fix ipset compilation with gcc 4.4.7 related to C99 initialization of unnamed unions, patch from Elad Raz. 5) Add a workaround to address inconsistent endianess in the res_id field of nfnetlink batch messages, reported by Florian Westphal. 6) Fix error paths of CT/synproxy since the conntrack template was moved to use kmalloc, patch from Daniel Borkmann. All of them look good to me to reach 4.2, I can route this to -stable myself too, just let me know what you prefer. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01netfilter: conntrack: use nf_ct_tmpl_free in CT/synproxy error pathsDaniel Borkmann1-1/+1
Commit 0838aa7fcfcd ("netfilter: fix netns dependencies with conntrack templates") migrated templates to the new allocator api, but forgot to update error paths for them in CT and synproxy to use nf_ct_tmpl_free() instead of nf_conntrack_free(). Due to that, memory is being freed into the wrong kmemcache, but also we drop the per net reference count of ct objects causing an imbalance. In Brad's case, this leads to a wrap-around of net->ct.count and thus lets __nf_conntrack_alloc() refuse to create a new ct object: [ 10.340913] xt_addrtype: ipv6 does not support BROADCAST matching [ 10.810168] nf_conntrack: table full, dropping packet [ 11.917416] r8169 0000:07:00.0 eth0: link up [ 11.917438] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 12.815902] nf_conntrack: table full, dropping packet [ 15.688561] nf_conntrack: table full, dropping packet [ 15.689365] nf_conntrack: table full, dropping packet [ 15.690169] nf_conntrack: table full, dropping packet [ 15.690967] nf_conntrack: table full, dropping packet [...] With slab debugging, it also reports the wrong kmemcache (kmalloc-512 vs. nf_conntrack_ffffffff81ce75c0) and reports poison overwrites, etc. Thus, to fix the problem, export and use nf_ct_tmpl_free() instead. Fixes: 0838aa7fcfcd ("netfilter: fix netns dependencies with conntrack templates") Reported-by: Brad Jackson <bjackson0971@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-28netfilter: reduce sparse warningsFlorian Westphal1-3/+3
bridge/netfilter/ebtables.c:290:26: warning: incorrect type in assignment (different modifiers) -> remove __pure annotation. ipv6/netfilter/ip6t_SYNPROXY.c:240:27: warning: cast from restricted __be16 -> switch ntohs to htons and vice versa. netfilter/core.c:391:30: warning: symbol 'nfq_ct_nat_hook' was not declared. Should it be static? -> delete it, got removed net/netfilter/nf_synproxy_core.c:221:48: warning: cast to restricted __be32 -> Use __be32 instead of u32. Tested with objdiff that these changes do not affect generated code. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-21Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextPablo Neira Ayuso1-4/+2
Resolve conflicts with conntrack template fixes. Conflicts: net/netfilter/nf_conntrack_core.c net/netfilter/nf_synproxy_core.c net/netfilter/xt_CT.c Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-08-17net: Change pseudohdr argument of inet_proto_csum_replace* to be a boolTom Herbert1-1/+1
inet_proto_csum_replace4,2,16 take a pseudohdr argument which indicates the checksum field carries a pseudo header. This argument should be a boolean instead of an int. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-11netfilter: nf_conntrack: push zone object into functionsDaniel Borkmann1-1/+3
This patch replaces the zone id which is pushed down into functions with the actual zone object. It's a bigger one-time change, but needed for later on extending zones with a direction parameter, and thus decoupling this additional information from all call-sites. No functional changes in this patch. The default zone becomes a global const object, namely nf_ct_zone_dflt and will be returned directly in various cases, one being, when there's f.e. no zoning support. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-30netfilter: nf_conntrack: checking for IS_ERR() instead of NULLDan Carpenter1-3/+1
We recently changed this from nf_conntrack_alloc() to nf_ct_tmpl_alloc() so the error handling needs to changed to check for NULL instead of IS_ERR(). Fixes: 0838aa7fcfcd ('netfilter: fix netns dependencies with conntrack templates') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-20netfilter: fix netns dependencies with conntrack templatesPablo Neira Ayuso1-4/+3
Quoting Daniel Borkmann: "When adding connection tracking template rules to a netns, f.e. to configure netfilter zones, the kernel will endlessly busy-loop as soon as we try to delete the given netns in case there's at least one template present, which is problematic i.e. if there is such bravery that the priviledged user inside the netns is assumed untrusted. Minimal example: ip netns add foo ip netns exec foo iptables -t raw -A PREROUTING -d 1.2.3.4 -j CT --zone 1 ip netns del foo What happens is that when nf_ct_iterate_cleanup() is being called from nf_conntrack_cleanup_net_list() for a provided netns, we always end up with a net->ct.count > 0 and thus jump back to i_see_dead_people. We don't get a soft-lockup as we still have a schedule() point, but the serving CPU spins on 100% from that point onwards. Since templates are normally allocated with nf_conntrack_alloc(), we also bump net->ct.count. The issue why they are not yet nf_ct_put() is because the per netns .exit() handler from x_tables (which would eventually invoke xt_CT's xt_ct_tg_destroy() that drops reference on info->ct) is called in the dependency chain at a *later* point in time than the per netns .exit() handler for the connection tracker. This is clearly a chicken'n'egg problem: after the connection tracker .exit() handler, we've teared down all the connection tracking infrastructure already, so rightfully, xt_ct_tg_destroy() cannot be invoked at a later point in time during the netns cleanup, as that would lead to a use-after-free. At the same time, we cannot make x_tables depend on the connection tracker module, so that the xt_ct_tg_destroy() would be invoked earlier in the cleanup chain." Daniel confirms this has to do with the order in which modules are loaded or having compiled nf_conntrack as modules while x_tables built-in. So we have no guarantees regarding the order in which netns callbacks are executed. Fix this by allocating the templates through kmalloc() from the respective SYNPROXY and CT targets, so they don't depend on the conntrack kmem cache. Then, release then via nf_ct_tmpl_free() from destroy_conntrack(). This branch is marked as unlikely since conntrack templates are rarely allocated and only from the configuration plane path. Note that templates are not kept in any list to avoid further dependencies with nf_conntrack anymore, thus, the tmpl larval list is removed. Reported-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Tested-by: Daniel Borkmann <daniel@iogearbox.net>
2015-06-18netfilter: use forward declaration instead of including linux/proc_fs.hPablo Neira Ayuso1-0/+1
We don't need to pull the full definitions in that file, a simple forward declaration is enough. Moreover, include linux/procfs.h from nf_synproxy_core, otherwise this hits a compilation error due to missing declarations, ie. net/netfilter/nf_synproxy_core.c: In function ‘synproxy_proc_init’: net/netfilter/nf_synproxy_core.c:326:2: error: implicit declaration of function ‘proc_create’ [-Werror=implicit-function-declaration] if (!proc_create("synproxy", S_IRUGO, net->proc_net_stat, ^ Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2014-02-05netfilter: nf_conntrack: don't release a conntrack with non-zero refcntPablo Neira Ayuso1-3/+2
With this patch, the conntrack refcount is initially set to zero and it is bumped once it is added to any of the list, so we fulfill Eric's golden rule which is that all released objects always have a refcount that equals zero. Andrey Vagin reports that nf_conntrack_free can't be called for a conntrack with non-zero ref-counter, because it can race with nf_conntrack_find_get(). A conntrack slab is created with SLAB_DESTROY_BY_RCU. Non-zero ref-counter says that this conntrack is used. So when we release a conntrack with non-zero counter, we break this assumption. CPU1 CPU2 ____nf_conntrack_find() nf_ct_put() destroy_conntrack() ... init_conntrack __nf_conntrack_alloc (set use = 1) atomic_inc_not_zero(&ct->use) (use = 2) if (!l4proto->new(ct, skb, dataoff, timeouts)) nf_conntrack_free(ct); (use = 2 !!!) ... __nf_conntrack_alloc (set use = 1) if (!nf_ct_key_equal(h, tuple, zone)) nf_ct_put(ct); (use = 0) destroy_conntrack() /* continue to work with CT */ After applying the path "[PATCH] netfilter: nf_conntrack: fix RCU race in nf_conntrack_find_get" another bug was triggered in destroy_conntrack(): <4>[67096.759334] ------------[ cut here ]------------ <2>[67096.759353] kernel BUG at net/netfilter/nf_conntrack_core.c:211! ... <4>[67096.759837] Pid: 498649, comm: atdd veid: 666 Tainted: G C --------------- 2.6.32-042stab084.18 #1 042stab084_18 /DQ45CB <4>[67096.759932] RIP: 0010:[<ffffffffa03d99ac>] [<ffffffffa03d99ac>] destroy_conntrack+0x15c/0x190 [nf_conntrack] <4>[67096.760255] Call Trace: <4>[67096.760255] [<ffffffff814844a7>] nf_conntrack_destroy+0x17/0x30 <4>[67096.760255] [<ffffffffa03d9bb5>] nf_conntrack_find_get+0x85/0x130 [nf_conntrack] <4>[67096.760255] [<ffffffffa03d9fb2>] nf_conntrack_in+0x352/0xb60 [nf_conntrack] <4>[67096.760255] [<ffffffffa048c771>] ipv4_conntrack_local+0x51/0x60 [nf_conntrack_ipv4] <4>[67096.760255] [<ffffffff81484419>] nf_iterate+0x69/0xb0 <4>[67096.760255] [<ffffffff814b5b00>] ? dst_output+0x0/0x20 <4>[67096.760255] [<ffffffff814845d4>] nf_hook_slow+0x74/0x110 <4>[67096.760255] [<ffffffff814b5b00>] ? dst_output+0x0/0x20 <4>[67096.760255] [<ffffffff814b66d5>] raw_sendmsg+0x775/0x910 <4>[67096.760255] [<ffffffff8104c5a8>] ? flush_tlb_others_ipi+0x128/0x130 <4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20 <4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20 <4>[67096.760255] [<ffffffff814c136a>] inet_sendmsg+0x4a/0xb0 <4>[67096.760255] [<ffffffff81444e93>] ? sock_sendmsg+0x13/0x140 <4>[67096.760255] [<ffffffff81444f97>] sock_sendmsg+0x117/0x140 <4>[67096.760255] [<ffffffff8102e299>] ? native_smp_send_reschedule+0x49/0x60 <4>[67096.760255] [<ffffffff81519beb>] ? _spin_unlock_bh+0x1b/0x20 <4>[67096.760255] [<ffffffff8109d930>] ? autoremove_wake_function+0x0/0x40 <4>[67096.760255] [<ffffffff814960f0>] ? do_ip_setsockopt+0x90/0xd80 <4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20 <4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20 <4>[67096.760255] [<ffffffff814457c9>] sys_sendto+0x139/0x190 <4>[67096.760255] [<ffffffff810efa77>] ? audit_syscall_entry+0x1d7/0x200 <4>[67096.760255] [<ffffffff810ef7c5>] ? __audit_syscall_exit+0x265/0x290 <4>[67096.760255] [<ffffffff81474daf>] compat_sys_socketcall+0x13f/0x210 <4>[67096.760255] [<ffffffff8104dea3>] ia32_sysret+0x0/0x5 I have reused the original title for the RFC patch that Andrey posted and most of the original patch description. Cc: Eric Dumazet <edumazet@google.com> Cc: Andrew Vagin <avagin@parallels.com> Cc: Florian Westphal <fw@strlen.de> Reported-by: Andrew Vagin <avagin@parallels.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Andrew Vagin <avagin@parallels.com>
2013-11-18netfilter: synproxy: correct wscale option passingMartin Topholm1-3/+4
Timestamp are used to store additional syncookie parameters such as sack, ecn, and wscale. The wscale value we need to encode is the client's wscale, since we can't recover that later in the session. Next overwrite the wscale option so the later synproxy_send_client_synack will send the backend's wscale to the client. Signed-off-by: Martin Topholm <mph@one.com> Reviewed-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-09-30netfilter: synproxy: fix BUG_ON triggered by corrupt TCP packetsPatrick McHardy1-5/+7
TCP packets hitting the SYN proxy through the SYNPROXY target are not validated by TCP conntrack. When th->doff is below 5, an underflow happens when calculating the options length, causing skb_header_pointer() to return NULL and triggering the BUG_ON(). Handle this case gracefully by checking for NULL instead of using BUG_ON(). Reported-by: Martin Topholm <mph@one.com> Tested-by: Martin Topholm <mph@one.com> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-09-04netfilter: synproxy_core: fix warning in __nf_ct_ext_add_length()Patrick McHardy1-2/+2
With CONFIG_NETFILTER_DEBUG we get the following warning during SYNPROXY init: [ 80.558906] WARNING: CPU: 1 PID: 4833 at net/netfilter/nf_conntrack_extend.c:80 __nf_ct_ext_add_length+0x217/0x220 [nf_conntrack]() The reason is that the conntrack template is set to confirmed before adding the extension and it is invalid to add extensions to already confirmed conntracks. Fix by adding the extensions before setting the conntrack to confirmed. Reported-by: Jesper Dangaard Brouer <jesper.brouer@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-28netfilter: add SYNPROXY core/targetPatrick McHardy1-0/+432
Add a SYNPROXY for netfilter. The code is split into two parts, the synproxy core with common functions and an address family specific target. The SYNPROXY receives the connection request from the client, responds with a SYN/ACK containing a SYN cookie and announcing a zero window and checks whether the final ACK from the client contains a valid cookie. It then establishes a connection to the original destination and, if successful, sends a window update to the client with the window size announced by the server. Support for timestamps, SACK, window scaling and MSS options can be statically configured as target parameters if the features of the server are known. If timestamps are used, the timestamp value sent back to the client in the SYN/ACK will be different from the real timestamp of the server. In order to now break PAWS, the timestamps are translated in the direction server->client. Signed-off-by: Patrick McHardy <kaber@trash.net> Tested-by: Martin Topholm <mph@one.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>