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2017-12-13ipv6: mcast: better catch silly mtu valuesEric Dumazet1-10/+15
syzkaller reported crashes in IPv6 stack [1] Xin Long found that lo MTU was set to silly values. IPv6 stack reacts to changes to small MTU, by disabling itself under RTNL. But there is a window where threads not using RTNL can see a wrong device mtu. This can lead to surprises, in mld code where it is assumed the mtu is suitable. Fix this by reading device mtu once and checking IPv6 minimal MTU. [1] skbuff: skb_over_panic: text:0000000010b86b8d len:196 put:20 head:000000003b477e60 data:000000000e85441e tail:0xd4 end:0xc0 dev:lo ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:104! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.15.0-rc2-mm1+ #39 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:skb_panic+0x15c/0x1f0 net/core/skbuff.c:100 RSP: 0018:ffff8801db307508 EFLAGS: 00010286 RAX: 0000000000000082 RBX: ffff8801c517e840 RCX: 0000000000000000 RDX: 0000000000000082 RSI: 1ffff1003b660e61 RDI: ffffed003b660e95 RBP: ffff8801db307570 R08: 1ffff1003b660e23 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff85bd4020 R13: ffffffff84754ed2 R14: 0000000000000014 R15: ffff8801c4e26540 FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000463610 CR3: 00000001c6698000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> skb_over_panic net/core/skbuff.c:109 [inline] skb_put+0x181/0x1c0 net/core/skbuff.c:1694 add_grhead.isra.24+0x42/0x3b0 net/ipv6/mcast.c:1695 add_grec+0xa55/0x1060 net/ipv6/mcast.c:1817 mld_send_cr net/ipv6/mcast.c:1903 [inline] mld_ifc_timer_expire+0x4d2/0x770 net/ipv6/mcast.c:2448 call_timer_fn+0x23b/0x840 kernel/time/timer.c:1320 expire_timers kernel/time/timer.c:1357 [inline] __run_timers+0x7e1/0xb60 kernel/time/timer.c:1660 run_timer_softirq+0x4c/0xb0 kernel/time/timer.c:1686 __do_softirq+0x29d/0xbb2 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1d3/0x210 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:540 [inline] smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:920 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Tested-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-21treewide: setup_timer() -> timer_setup()Kees Cook1-18/+15
This converts all remaining cases of the old setup_timer() API into using timer_setup(), where the callback argument is the structure already holding the struct timer_list. These should have no behavioral changes, since they just change which pointer is passed into the callback with the same available pointers after conversion. It handles the following examples, in addition to some other variations. Casting from unsigned long: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... setup_timer(&ptr->my_timer, my_callback, ptr); and forced object casts: void my_callback(struct something *ptr) { ... } ... setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr); become: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... timer_setup(&ptr->my_timer, my_callback, 0); Direct function assignments: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... ptr->my_timer.function = my_callback; have a temporary cast added, along with converting the args: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback; And finally, callbacks without a data assignment: void my_callback(unsigned long data) { ... } ... setup_timer(&ptr->my_timer, my_callback, 0); have their argument renamed to verify they're unused during conversion: void my_callback(struct timer_list *unused) { ... } ... timer_setup(&ptr->my_timer, my_callback, 0); The conversion is done with the following Coccinelle script: spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/timer_setup.cocci @fix_address_of@ expression e; @@ setup_timer( -&(e) +&e , ...) // Update any raw setup_timer() usages that have a NULL callback, but // would otherwise match change_timer_function_usage, since the latter // will update all function assignments done in the face of a NULL // function initialization in setup_timer(). @change_timer_function_usage_NULL@ expression _E; identifier _timer; type _cast_data; @@ ( -setup_timer(&_E->_timer, NULL, _E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E->_timer, NULL, (_cast_data)_E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E._timer, NULL, &_E); +timer_setup(&_E._timer, NULL, 0); | -setup_timer(&_E._timer, NULL, (_cast_data)&_E); +timer_setup(&_E._timer, NULL, 0); ) @change_timer_function_usage@ expression _E; identifier _timer; struct timer_list _stl; identifier _callback; type _cast_func, _cast_data; @@ ( -setup_timer(&_E->_timer, _callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | _E->_timer@_stl.function = _callback; | _E->_timer@_stl.function = &_callback; | _E->_timer@_stl.function = (_cast_func)_callback; | _E->_timer@_stl.function = (_cast_func)&_callback; | _E._timer@_stl.function = _callback; | _E._timer@_stl.function = &_callback; | _E._timer@_stl.function = (_cast_func)_callback; | _E._timer@_stl.function = (_cast_func)&_callback; ) // callback(unsigned long arg) @change_callback_handle_cast depends on change_timer_function_usage@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; identifier _handle; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { ( ... when != _origarg _handletype *_handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg ) } // callback(unsigned long arg) without existing variable @change_callback_handle_cast_no_arg depends on change_timer_function_usage && !change_callback_handle_cast@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { + _handletype *_origarg = from_timer(_origarg, t, _timer); + ... when != _origarg - (_handletype *)_origarg + _origarg ... when != _origarg } // Avoid already converted callbacks. @match_callback_converted depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier t; @@ void _callback(struct timer_list *t) { ... } // callback(struct something *handle) @change_callback_handle_arg depends on change_timer_function_usage && !match_callback_converted && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; @@ void _callback( -_handletype *_handle +struct timer_list *t ) { + _handletype *_handle = from_timer(_handle, t, _timer); ... } // If change_callback_handle_arg ran on an empty function, remove // the added handler. @unchange_callback_handle_arg depends on change_timer_function_usage && change_callback_handle_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; identifier t; @@ void _callback(struct timer_list *t) { - _handletype *_handle = from_timer(_handle, t, _timer); } // We only want to refactor the setup_timer() data argument if we've found // the matching callback. This undoes changes in change_timer_function_usage. @unchange_timer_function_usage depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg && !change_callback_handle_arg@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type change_timer_function_usage._cast_data; @@ ( -timer_setup(&_E->_timer, _callback, 0); +setup_timer(&_E->_timer, _callback, (_cast_data)_E); | -timer_setup(&_E._timer, _callback, 0); +setup_timer(&_E._timer, _callback, (_cast_data)&_E); ) // If we fixed a callback from a .function assignment, fix the // assignment cast now. @change_timer_function_assignment depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_func; typedef TIMER_FUNC_TYPE; @@ ( _E->_timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -&_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)_callback; +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -&_callback; +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; ) // Sometimes timer functions are called directly. Replace matched args. @change_timer_function_calls depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression _E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_data; @@ _callback( ( -(_cast_data)_E +&_E->_timer | -(_cast_data)&_E +&_E._timer | -_E +&_E->_timer ) ) // If a timer has been configured without a data argument, it can be // converted without regard to the callback argument, since it is unused. @match_timer_function_unused_data@ expression _E; identifier _timer; identifier _callback; @@ ( -setup_timer(&_E->_timer, _callback, 0); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0L); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0UL); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0L); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0UL); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_timer, _callback, 0); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0L); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0UL); +timer_setup(&_timer, _callback, 0); | -setup_timer(_timer, _callback, 0); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0L); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0UL); +timer_setup(_timer, _callback, 0); ) @change_callback_unused_data depends on match_timer_function_unused_data@ identifier match_timer_function_unused_data._callback; type _origtype; identifier _origarg; @@ void _callback( -_origtype _origarg +struct timer_list *unused ) { ... when != _origarg } Signed-off-by: Kees Cook <keescook@chromium.org>
2017-07-04net, ipv6: convert ifmcaddr6.mca_refcnt from atomic_t to refcount_tReshetova, Elena1-9/+9
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16networking: make skb_put & friends return void pointersJohannes Berg1-2/+2
It seems like a historic accident that these return unsigned char *, and in many places that means casts are required, more often than not. Make these functions (skb_put, __skb_put and pskb_put) return void * and remove all the casts across the tree, adding a (u8 *) cast only where the unsigned char pointer was used directly, all done with the following spatch: @@ expression SKB, LEN; typedef u8; identifier fn = { skb_put, __skb_put }; @@ - *(fn(SKB, LEN)) + *(u8 *)fn(SKB, LEN) @@ expression E, SKB, LEN; identifier fn = { skb_put, __skb_put }; type T; @@ - E = ((T *)(fn(SKB, LEN))) + E = fn(SKB, LEN) which actually doesn't cover pskb_put since there are only three users overall. A handful of stragglers were converted manually, notably a macro in drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many instances in net/bluetooth/hci_sock.c. In the former file, I also had to fix one whitespace problem spatch introduced. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16networking: introduce and use skb_put_data()Johannes Berg1-2/+2
A common pattern with skb_put() is to just want to memcpy() some data into the new space, introduce skb_put_data() for this. An spatch similar to the one for skb_put_zero() converts many of the places using it: @@ identifier p, p2; expression len, skb, data; type t, t2; @@ ( -p = skb_put(skb, len); +p = skb_put_data(skb, data, len); | -p = (t)skb_put(skb, len); +p = skb_put_data(skb, data, len); ) ( p2 = (t2)p; -memcpy(p2, data, len); | -memcpy(p, data, len); ) @@ type t, t2; identifier p, p2; expression skb, data; @@ t *p; ... ( -p = skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); | -p = (t *)skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); ) ( p2 = (t2)p; -memcpy(p2, data, sizeof(*p)); | -memcpy(p, data, sizeof(*p)); ) @@ expression skb, len, data; @@ -memcpy(skb_put(skb, len), data, len); +skb_put_data(skb, data, len); (again, manually post-processed to retain some comments) Reviewed-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16networking: convert many more places to skb_put_zero()Johannes Berg1-2/+1
There were many places that my previous spatch didn't find, as pointed out by yuan linyu in various patches. The following spatch found many more and also removes the now unnecessary casts: @@ identifier p, p2; expression len; expression skb; type t, t2; @@ ( -p = skb_put(skb, len); +p = skb_put_zero(skb, len); | -p = (t)skb_put(skb, len); +p = skb_put_zero(skb, len); ) ... when != p ( p2 = (t2)p; -memset(p2, 0, len); | -memset(p, 0, len); ) @@ type t, t2; identifier p, p2; expression skb; @@ t *p; ... ( -p = skb_put(skb, sizeof(t)); +p = skb_put_zero(skb, sizeof(t)); | -p = (t *)skb_put(skb, sizeof(t)); +p = skb_put_zero(skb, sizeof(t)); ) ... when != p ( p2 = (t2)p; -memset(p2, 0, sizeof(*p)); | -memset(p, 0, sizeof(*p)); ) @@ expression skb, len; @@ -memset(skb_put(skb, len), 0, len); +skb_put_zero(skb, len); Apply it to the tree (with one manual fixup to keep the comment in vxlan.c, which spatch removed.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-28ipv6: add support for NETDEV_RESEND_IGMP eventVlad Yasevich1-1/+48
This patch adds support for NETDEV_RESEND_IGMP event similar to how it works for IPv4. Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()Hangbin Liu1-0/+1
In function igmpv3/mld_add_delrec() we allocate pmc and put it in idev->mc_tomb, so we should free it when we don't need it in del_delrec(). But I removed kfree(pmc) incorrectly in latest two patches. Now fix it. Fixes: 24803f38a5c0 ("igmp: do not remove igmp souce list info when ...") Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when ...") Reported-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-16mld: do not remove mld souce list info when set link downHangbin Liu1-21/+30
This is an IPv6 version of commit 24803f38a5c0 ("igmp: do not remove igmp souce list..."). In mld_del_delrec(), we will restore back all source filter info instead of flush them. Move mld_clear_delrec() from ipv6_mc_down() to ipv6_mc_destroy_dev() since we should not remove source list info when set link down. Remove igmp6_group_dropped() in ipv6_mc_destroy_dev() since we have called it in ipv6_mc_down(). Also clear all source info after igmp6_group_dropped() instead of in it because ipv6_mc_down() will call igmp6_group_dropped(). Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-21ipv6: fix a potential deadlock in do_ipv6_setsockopt()WANG Cong1-5/+12
Baozeng reported this deadlock case: CPU0 CPU1 ---- ---- lock([ 165.136033] sk_lock-AF_INET6); lock([ 165.136033] rtnl_mutex); lock([ 165.136033] sk_lock-AF_INET6); lock([ 165.136033] rtnl_mutex); Similar to commit 87e9f0315952 ("ipv4: fix a potential deadlock in mcast getsockopt() path") this is due to we still have a case, ipv6_sock_mc_close(), where we acquire sk_lock before rtnl_lock. Close this deadlock with the similar solution, that is always acquire rtnl lock first. Fixes: baf606d9c9b1 ("ipv4,ipv6: grab rtnl before locking the socket") Reported-by: Baozeng Ding <sploving1@gmail.com> Tested-by: Baozeng Ding <sploving1@gmail.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-08net/multicast: should not send source list records when have filter mode changeHangbin Liu1-0/+10
Based on RFC3376 5.1 and RFC3810 6.1 If the per-interface listening change that triggers the new report is a filter mode change, then the next [Robustness Variable] State Change Reports will include a Filter Mode Change Record. This applies even if any number of source list changes occur in that period. Old State New State State Change Record Sent --------- --------- ------------------------ INCLUDE (A) EXCLUDE (B) TO_EX (B) EXCLUDE (A) INCLUDE (B) TO_IN (B) So we should not send source-list change if there is a filter-mode change. Here are two scenarios: 1. Group deleted and filter mode is EXCLUDE, which means we need send a TO_IN { }. 2. Not group deleted, but has pcm->crcount, which means we need send a normal filter-mode-change. At the same time, if the type is ALLOW or BLOCK, and have psf->sf_crcount, we stop add records and decrease sf_crcount directly Reference: https://www.ietf.org/mail-archive/web/magma/current/msg01274.html Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-03mld, igmp: Fix reserved tailroom calculationBenjamin Poirier1-2/+1
The current reserved_tailroom calculation fails to take hlen and tlen into account. skb: [__hlen__|__data____________|__tlen___|__extra__] ^ ^ head skb_end_offset In this representation, hlen + data + tlen is the size passed to alloc_skb. "extra" is the extra space made available in __alloc_skb because of rounding up by kmalloc. We can reorder the representation like so: [__hlen__|__data____________|__extra__|__tlen___] ^ ^ head skb_end_offset The maximum space available for ip headers and payload without fragmentation is min(mtu, data + extra). Therefore, reserved_tailroom = data + extra + tlen - min(mtu, data + extra) = skb_end_offset - hlen - min(mtu, skb_end_offset - hlen - tlen) = skb_tailroom - min(mtu, skb_tailroom - tlen) ; after skb_reserve(hlen) Compare the second line to the current expression: reserved_tailroom = skb_end_offset - min(mtu, skb_end_offset) and we can see that hlen and tlen are not taken into account. The min() in the third line can be expanded into: if mtu < skb_tailroom - tlen: reserved_tailroom = skb_tailroom - mtu else: reserved_tailroom = tlen Depending on hlen, tlen, mtu and the number of multicast address records, the current code may output skbs that have less tailroom than dev->needed_tailroom or it may output more skbs than needed because not all space available is used. Fixes: 4c672e4b ("ipv6: mld: fix add_grhead skb_over_panic for devs with large MTUs") Signed-off-by: Benjamin Poirier <bpoirier@suse.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-16snmp: Remove duplicate OUTMCAST stat incrementNeil Horman1-2/+0
the OUTMCAST stat is double incremented, getting bumped once in the mcast code itself, and again in the common ip output path. Remove the mcast bump, as its not needed Validated by the reporter, with good results Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Claus Jensen <claus.jensen@microsemi.com> CC: Claus Jensen <claus.jensen@microsemi.com> CC: David Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08net: Pass net into dst_output and remove dst_output_okfnEric W. Biederman1-2/+2
Replace dst_output_okfn with dst_output Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17netfilter: Pass net into okfnEric W. Biederman1-2/+2
This is immediately motivated by the bridge code that chains functions that call into netfilter. Without passing net into the okfns the bridge code would need to guess about the best expression for the network namespace to process packets in. As net is frequently one of the first things computed in continuation functions after netfilter has done it's job passing in the desired network namespace is in many cases a code simplification. To support this change the function dst_output_okfn is introduced to simplify passing dst_output as an okfn. For the moment dst_output_okfn just silently drops the struct net. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17netfilter: Pass struct net into the netfilter hooksEric W. Biederman1-3/+4
Pass a network namespace parameter into the netfilter hooks. At the call site of the netfilter hooks the path a packet is taking through the network stack is well known which allows the network namespace to be easily and reliabily. This allows the replacement of magic code like "dev_net(state->in?:state->out)" that appears at the start of most netfilter hooks with "state->net". In almost all cases the network namespace passed in is derived from the first network device passed in, guaranteeing those paths will not see any changes in practice. The exceptions are: xfrm/xfrm_output.c:xfrm_output_resume() xs_net(skb_dst(skb)->xfrm) ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont() ip_vs_conn_net(cp) ipvs/ip_vs_xmit.c:ip_vs_send_or_cont() ip_vs_conn_net(cp) ipv4/raw.c:raw_send_hdrinc() sock_net(sk) ipv6/ip6_output.c:ip6_xmit() sock_net(sk) ipv6/ndisc.c:ndisc_send_skb() dev_net(skb->dev) not dev_net(dst->dev) ipv6/raw.c:raw6_send_hdrinc() sock_net(sk) br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev In all cases these exceptions seem to be a better expression for the network namespace the packet is being processed in then the historic "dev_net(in?in:out)". I am documenting them in case something odd pops up and someone starts trying to track down what happened. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17net: Merge dst_output and dst_output_skEric W. Biederman1-2/+2
Add a sock paramter to dst_output making dst_output_sk superfluous. Add a skb->sk parameter to all of the callers of dst_output Have the callers of dst_output_sk call dst_output. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-07netfilter: Pass socket pointer down through okfn().David Miller1-4/+5
On the output paths in particular, we have to sometimes deal with two socket contexts. First, and usually skb->sk, is the local socket that generated the frame. And second, is potentially the socket used to control a tunneling socket, such as one the encapsulates using UDP. We do not want to disassociate skb->sk when encapsulating in order to fix this, because that would break socket memory accounting. The most extreme case where this can cause huge problems is an AF_PACKET socket transmitting over a vxlan device. We hit code paths doing checks that assume they are dealing with an ipv4 socket, but are actually operating upon the AF_PACKET one. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31ipv6: coding style: comparison for inequality with NULLIan Morris1-8/+8
The ipv6 code uses a mixture of coding styles. In some instances check for NULL pointer is done as x != NULL and sometimes as x. x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31ipv6: coding style: comparison for equality with NULLIan Morris1-7/+7
The ipv6 code uses a mixture of coding styles. In some instances check for NULL pointer is done as x == NULL and sometimes as !x. !x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18ipv4, ipv6: kill ip_mc_{join, leave}_group and ipv6_sock_mc_{join, drop}Marcelo Ricardo Leitner1-27/+3
in favor of their inner __ ones, which doesn't grab rtnl. As these functions need to operate on a locked socket, we can't be grabbing rtnl by then. It's too late and doing so causes reversed locking. So this patch: - move rtnl handling to callers instead while already fixing some reversed locking situations, like on vxlan and ipvs code. - renames __ ones to not have the __ mark: __ip_mc_{join,leave}_group -> ip_mc_{join,leave}_group __ipv6_sock_mc_{join,drop} -> ipv6_sock_mc_{join,drop} Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27multicast: Extend ip address command to enable multicast group join/leave onMadhu Challa1-4/+16
Joining multicast group on ethernet level via "ip maddr" command would not work if we have an Ethernet switch that does igmp snooping since the switch would not replicate multicast packets on ports that did not have IGMP reports for the multicast addresses. Linux vxlan interfaces created via "ip link add vxlan" have the group option that enables then to do the required join. By extending ip address command with option "autojoin" we can get similar functionality for openvswitch vxlan interfaces as well as other tunneling mechanisms that need to receive multicast traffic. The kernel code is structured similar to how the vxlan driver does a group join / leave. example: ip address add 224.1.1.10/24 dev eth5 autojoin ip address del 224.1.1.10/24 dev eth5 Signed-off-by: Madhu Challa <challa@noironetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27igmp v6: add __ipv6_sock_mc_join and __ipv6_sock_mc_dropMadhu Challa1-9/+31
Based on the igmp v4 changes from Eric Dumazet. 959d10f6bbf6("igmp: add __ip_mc_{join|leave}_group()") These changes are needed to perform igmp v6 join/leave while RTNL is held. Make ipv6_sock_mc_join and ipv6_sock_mc_drop wrappers around __ipv6_sock_mc_join and __ipv6_sock_mc_drop to avoid proliferation of work queues. Signed-off-by: Madhu Challa <challa@noironetworks.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-05ipv6: mld: fix add_grhead skb_over_panic for devs with large MTUsDaniel Borkmann1-4/+5
It has been reported that generating an MLD listener report on devices with large MTUs (e.g. 9000) and a high number of IPv6 addresses can trigger a skb_over_panic(): skbuff: skb_over_panic: text:ffffffff80612a5d len:3776 put:20 head:ffff88046d751000 data:ffff88046d751010 tail:0xed0 end:0xec0 dev:port1 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:100! invalid opcode: 0000 [#1] SMP Modules linked in: ixgbe(O) CPU: 3 PID: 0 Comm: swapper/3 Tainted: G O 3.14.23+ #4 [...] Call Trace: <IRQ> [<ffffffff80578226>] ? skb_put+0x3a/0x3b [<ffffffff80612a5d>] ? add_grhead+0x45/0x8e [<ffffffff80612e3a>] ? add_grec+0x394/0x3d4 [<ffffffff80613222>] ? mld_ifc_timer_expire+0x195/0x20d [<ffffffff8061308d>] ? mld_dad_timer_expire+0x45/0x45 [<ffffffff80255b5d>] ? call_timer_fn.isra.29+0x12/0x68 [<ffffffff80255d16>] ? run_timer_softirq+0x163/0x182 [<ffffffff80250e6f>] ? __do_softirq+0xe0/0x21d [<ffffffff8025112b>] ? irq_exit+0x4e/0xd3 [<ffffffff802214bb>] ? smp_apic_timer_interrupt+0x3b/0x46 [<ffffffff8063f10a>] ? apic_timer_interrupt+0x6a/0x70 mld_newpack() skb allocations are usually requested with dev->mtu in size, since commit 72e09ad107e7 ("ipv6: avoid high order allocations") we have changed the limit in order to be less likely to fail. However, in MLD/IGMP code, we have some rather ugly AVAILABLE(skb) macros, which determine if we may end up doing an skb_put() for adding another record. To avoid possible fragmentation, we check the skb's tailroom as skb->dev->mtu - skb->len, which is a wrong assumption as the actual max allocation size can be much smaller. The IGMP case doesn't have this issue as commit 57e1ab6eaddc ("igmp: refine skb allocations") stores the allocation size in the cb[]. Set a reserved_tailroom to make it fit into the MTU and use skb_availroom() helper instead. This also allows to get rid of igmp_skb_size(). Reported-by: Wei Liu <lw1a2.jing@gmail.com> Fixes: 72e09ad107e7 ("ipv6: avoid high order allocations") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: David L Stevens <david.stevens@oracle.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-05net: Convert SEQ_START_TOKEN/seq_printf to seq_putsJoe Perches1-5/+1
Using a single fixed string is smaller code size than using a format and many string arguments. Reduces overall code size a little. $ size net/ipv4/igmp.o* net/ipv6/mcast.o* net/ipv6/ip6_flowlabel.o* text data bss dec hex filename 34269 7012 14824 56105 db29 net/ipv4/igmp.o.new 34315 7012 14824 56151 db57 net/ipv4/igmp.o.old 30078 7869 13200 51147 c7cb net/ipv6/mcast.o.new 30105 7869 13200 51174 c7e6 net/ipv6/mcast.o.old 11434 3748 8580 23762 5cd2 net/ipv6/ip6_flowlabel.o.new 11491 3748 8580 23819 5d0b net/ipv6/ip6_flowlabel.o.old Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-22ipv6: mld: answer mldv2 queries with mldv1 reports in mldv1 fallbackDaniel Borkmann1-10/+31
RFC2710 (MLDv1), section 3.7. says: The length of a received MLD message is computed by taking the IPv6 Payload Length value and subtracting the length of any IPv6 extension headers present between the IPv6 header and the MLD message. If that length is greater than 24 octets, that indicates that there are other fields present *beyond* the fields described above, perhaps belonging to a *future backwards-compatible* version of MLD. An implementation of the version of MLD specified in this document *MUST NOT* send an MLD message longer than 24 octets and MUST ignore anything past the first 24 octets of a received MLD message. RFC3810 (MLDv2), section 8.2.1. states for *listeners* regarding presence of MLDv1 routers: In order to be compatible with MLDv1 routers, MLDv2 hosts MUST operate in version 1 compatibility mode. [...] When Host Compatibility Mode is MLDv2, a host acts using the MLDv2 protocol on that interface. When Host Compatibility Mode is MLDv1, a host acts in MLDv1 compatibility mode, using *only* the MLDv1 protocol, on that interface. [...] While section 8.3.1. specifies *router* behaviour regarding presence of MLDv1 routers: MLDv2 routers may be placed on a network where there is at least one MLDv1 router. The following requirements apply: If an MLDv1 router is present on the link, the Querier MUST use the *lowest* version of MLD present on the network. This must be administratively assured. Routers that desire to be compatible with MLDv1 MUST have a configuration option to act in MLDv1 mode; if an MLDv1 router is present on the link, the system administrator must explicitly configure all MLDv2 routers to act in MLDv1 mode. When in MLDv1 mode, the Querier MUST send periodic General Queries truncated at the Multicast Address field (i.e., 24 bytes long), and SHOULD also warn about receiving an MLDv2 Query (such warnings must be rate-limited). The Querier MUST also fill in the Maximum Response Delay in the Maximum Response Code field, i.e., the exponential algorithm described in section 5.1.3. is not used. [...] That means that we should not get queries from different versions of MLD. When there's a MLDv1 router present, MLDv2 enforces truncation and MRC == MRD (both fields are overlapping within the 24 octet range). Section 8.3.2. specifies behaviour in the presence of MLDv1 multicast address *listeners*: MLDv2 routers may be placed on a network where there are hosts that have not yet been upgraded to MLDv2. In order to be compatible with MLDv1 hosts, MLDv2 routers MUST operate in version 1 compatibility mode. MLDv2 routers keep a compatibility mode per multicast address record. The compatibility mode of a multicast address is determined from the Multicast Address Compatibility Mode variable, which can be in one of the two following states: MLDv1 or MLDv2. The Multicast Address Compatibility Mode of a multicast address record is set to MLDv1 whenever an MLDv1 Multicast Listener Report is *received* for that multicast address. At the same time, the Older Version Host Present timer for the multicast address is set to Older Version Host Present Timeout seconds. The timer is re-set whenever a new MLDv1 Report is received for that multicast address. If the Older Version Host Present timer expires, the router switches back to Multicast Address Compatibility Mode of MLDv2 for that multicast address. [...] That means, what can happen is the following scenario, that hosts can act in MLDv1 compatibility mode when they previously have received an MLDv1 query (or, simply operate in MLDv1 mode-only); and at the same time, an MLDv2 router could start up and transmits MLDv2 startup query messages while being unaware of the current operational mode. Given RFC2710, section 3.7 we would need to answer to that with an MLDv1 listener report, so that the router according to RFC3810, section 8.3.2. would receive that and internally switch to MLDv1 compatibility as well. Right now, I believe since the initial implementation of MLDv2, Linux hosts would just silently drop such MLDv2 queries instead of replying with an MLDv1 listener report, which would prevent a MLDv2 router going into fallback mode (until it receives other MLDv1 queries). Since the mapping of MRC to MRD in exactly such cases can make use of the exponential algorithm from 5.1.3, we cannot [strictly speaking] be aware in MLDv1 of the encoding in MRC, it seems also not mentioned by the RFC. Since encodings are the same up to 32767, assume in such a situation this value as a hard upper limit we would clamp. We have asked one of the RFC authors on that regard, and he mentioned that there seem not to be any implementations that make use of that exponential algorithm on startup messages. In any case, this patch fixes this MLD interoperability issue. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13ipv6: refactor ipv6_dev_mc_inc()WANG Cong1-33/+49
Refactor out allocation and initialization and make the refcount code more readable. Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13ipv6: update the comment in mcast.cWANG Cong1-7/+5
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13ipv6: drop some rcu_read_lock in mcastWANG Cong1-13/+4
Similarly the code is already protected by rtnl lock. Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13ipv6: drop ipv6_sk_mc_lock in mcastWANG Cong1-16/+2
Similarly the code is already protected by rtnl lock. Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-09ipv6: mcast: remove dead debugging definesDaniel Borkmann1-9/+0
It's not used anywhere, so just remove these. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+14
2014-09-05ipv6: fix rtnl locking in setsockopt for anycast and multicastSabrina Dubroca1-0/+14
Calling setsockopt with IPV6_JOIN_ANYCAST or IPV6_LEAVE_ANYCAST triggers the assertion in addrconf_join_solict()/addrconf_leave_solict() ipv6_sock_ac_join(), ipv6_sock_ac_drop(), ipv6_sock_ac_close() need to take RTNL before calling ipv6_dev_ac_inc/dec. Same thing with ipv6_sock_mc_join(), ipv6_sock_mc_drop(), ipv6_sock_mc_close() before calling ipv6_dev_mc_inc/dec. This patch moves ASSERT_RTNL() up a level in the call stack. Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reported-by: Tommi Rantala <tt.rantala@gmail.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-04ipv6: add sysctl_mld_qrv to configure query robustness variableHannes Frederic Sowa1-10/+15
This patch adds a new sysctl_mld_qrv knob to configure the mldv1/v2 query robustness variable. It specifies how many retransmit of unsolicited mld retransmit should happen. Admins might want to tune this on lossy links. Also reset mld state on interface down/up, so we pick up new sysctl settings during interface up event. IPv6 certification requests this knob to be available. I didn't make this knob netns specific, as it is mostly a setting in a physical environment and should be per host. Cc: Flavio Leitner <fbl@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Flavio Leitner <fbl@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-24ipv6: White-space cleansing : Line LayoutsIan Morris1-50/+50
This patch makes no changes to the logic of the code but simply addresses coding style issues as detected by checkpatch. Both objdump and diff -w show no differences. A number of items are addressed in this patch: * Multiple spaces converted to tabs * Spaces before tabs removed. * Spaces in pointer typing cleansed (char *)foo etc. * Remove space after sizeof * Ensure spacing around comparators such as if statements. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27ipv6: Fix MLD Query message checkHangbin Liu1-2/+11
Based on RFC3810 6.2, we also need to check the hop limit and router alert option besides source address. Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-31ipv6: some ipv6 statistic counters failed to disable bhHannes Frederic Sowa1-5/+6
After commit c15b1ccadb323ea ("ipv6: move DAD and addrconf_verify processing to workqueue") some counters are now updated in process context and thus need to disable bh before doing so, otherwise deadlocks can happen on 32-bit archs. Fabio Estevam noticed this while while mounting a NFS volume on an ARM board. As a compensation for missing this I looked after the other *_STATS_BH and found three other calls which need updating: 1) icmp6_send: ip6_fragment -> icmpv6_send -> icmp6_send (error handling) 2) ip6_push_pending_frames: rawv6_sendmsg -> rawv6_push_pending_frames -> ... (only in case of icmp protocol with raw sockets in error handling) 3) ping6_v6_sendmsg (error handling) Fixes: c15b1ccadb323ea ("ipv6: move DAD and addrconf_verify processing to workqueue") Reported-by: Fabio Estevam <festevam@gmail.com> Tested-by: Fabio Estevam <fabio.estevam@freescale.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17ipv6: send Change Status Report after DAD is completedFlavio Leitner1-24/+33
The RFC 3810 defines two type of messages for multicast listeners. The "Current State Report" message, as the name implies, refreshes the *current* state to the querier. Since the querier sends Query messages periodically, there is no need to retransmit the report. On the other hand, any change should be reported immediately using "State Change Report" messages. Since it's an event triggered by a change and that it can be affected by packet loss, the rfc states it should be retransmitted [RobVar] times to make sure routers will receive timely. Currently, we are sending "Current State Reports" after DAD is completed. Before that, we send messages using unspecified address (::) which should be silently discarded by routers. This patch changes to send "State Change Report" messages after DAD is completed fixing the behavior to be RFC compliant and also to pass TAHI IPv6 testsuite. Signed-off-by: Flavio Leitner <fbl@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14net: replace macros net_random and net_srandom with direct calls to prandomAruna-Hewapathirane1-5/+5
This patch removes the net_random and net_srandom macros and replaces them with direct calls to the prandom ones. As new commits only seem to use prandom_u32 there is no use to keep them around. This change makes it easier to grep for users of prandom_u32. Signed-off-by: Aruna-Hewapathirane <aruna.hewapathirane@gmail.com> Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-30ipv6 mcast: use in6_dev_put in timer handlers instead of __in6_dev_putSalam Noureddine1-3/+3
It is possible for the timer handlers to run after the call to ipv6_mc_down so use in6_dev_put instead of __in6_dev_put in the handler function in order to do proper cleanup when the refcnt reaches 0. Otherwise, the refcnt can reach zero without the inet6_dev being destroyed and we end up leaking a reference to the net_device and see messages like the following, unregister_netdevice: waiting for eth0 to become free. Usage count = 1 Tested on linux-3.4.43. Signed-off-by: Salam Noureddine <noureddine@aristanetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04net: ipv6: mld: introduce mld_{gq, ifc, dad}_stop_timer functionsDaniel Borkmann1-16/+25
We already have mld_{gq,ifc,dad}_start_timer() functions, so introduce mld_{gq,ifc,dad}_stop_timer() functions to reduce code size and make it more readable. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04net: ipv6: mld: refactor query processing into v1/v2 functionsDaniel Borkmann1-33/+56
Make igmp6_event_query() a bit easier to read by refactoring code parts into mld_process_v1() and mld_process_v2(). Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04net: ipv6: mld: similarly to MLDv2 have min max_delay of 1Daniel Borkmann1-7/+7
Similarly as we do in MLDv2 queries, set a forged MLDv1 query with 0 ms mld_maxdelay to minimum timer shot time of 1 jiffies. This is eventually done in igmp6_group_queried() anyway, so we can simplify a check there. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04net: ipv6: mld: implement RFC3810 MLDv2 mode onlyDaniel Borkmann1-4/+30
RFC3810, 10. Security Considerations says under subsection 10.1. Query Message: A forged Version 1 Query message will put MLDv2 listeners on that link in MLDv1 Host Compatibility Mode. This scenario can be avoided by providing MLDv2 hosts with a configuration option to ignore Version 1 messages completely. Hence, implement a MLDv2-only mode that will ignore MLDv1 traffic: echo 2 > /proc/sys/net/ipv6/conf/ethX/force_mld_version or echo 2 > /proc/sys/net/ipv6/conf/all/force_mld_version Note that <all> device has a higher precedence as it was previously also the case in the macro MLD_V1_SEEN() that would "short-circuit" if condition on <all> case. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04net: ipv6: mld: get rid of MLDV2_MRC and simplify calculationDaniel Borkmann1-16/+2
Get rid of MLDV2_MRC and use our new macros for mantisse and exponent to calculate Maximum Response Delay out of the Maximum Response Code. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04net: ipv6: mld: clean up MLD_V1_SEEN macroDaniel Borkmann1-13/+21
Replace the macro with a function to make it more readable. GCC will eventually decide whether to inline this or not (also, that's not fast-path anyway). Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04net: ipv6: mld: fix v1/v2 switchback timeout to rfc3810, 9.12.Daniel Borkmann1-6/+110
i) RFC3810, 9.2. Query Interval [QI] says: The Query Interval variable denotes the interval between General Queries sent by the Querier. Default value: 125 seconds. [...] ii) RFC3810, 9.3. Query Response Interval [QRI] says: The Maximum Response Delay used to calculate the Maximum Response Code inserted into the periodic General Queries. Default value: 10000 (10 seconds) [...] The number of seconds represented by the [Query Response Interval] must be less than the [Query Interval]. iii) RFC3810, 9.12. Older Version Querier Present Timeout [OVQPT] says: The Older Version Querier Present Timeout is the time-out for transitioning a host back to MLDv2 Host Compatibility Mode. When an MLDv1 query is received, MLDv2 hosts set their Older Version Querier Present Timer to [Older Version Querier Present Timeout]. This value MUST be ([Robustness Variable] times (the [Query Interval] in the last Query received)) plus ([Query Response Interval]). Hence, on *default* the timeout results in: [RV] = 2, [QI] = 125sec, [QRI] = 10sec [OVQPT] = [RV] * [QI] + [QRI] = 260sec Having that said, we currently calculate [OVQPT] (here given as 'switchback' variable) as ... switchback = (idev->mc_qrv + 1) * max_delay RFC3810, 9.12. says "the [Query Interval] in the last Query received". In section "9.14. Configuring timers", it is said: This section is meant to provide advice to network administrators on how to tune these settings to their network. Ambitious router implementations might tune these settings dynamically based upon changing characteristics of the network. [...] iv) RFC38010, 9.14.2. Query Interval: The overall level of periodic MLD traffic is inversely proportional to the Query Interval. A longer Query Interval results in a lower overall level of MLD traffic. The value of the Query Interval MUST be equal to or greater than the Maximum Response Delay used to calculate the Maximum Response Code inserted in General Query messages. I assume that was why switchback is calculated as is (3 * max_delay), although this setting seems to be meant for routers only to configure their [QI] interval for non-default intervals. So usage here like this is clearly wrong. Concluding, the current behaviour in IPv6's multicast code is not conform to the RFC as switch back is calculated wrongly. That is, it has a too small value, so MLDv2 hosts switch back again to MLDv2 way too early, i.e. ~30secs instead of ~260secs on default. Hence, introduce necessary helper functions and fix this up properly as it should be. Introduced in 06da92283 ("[IPV6]: Add MLDv2 support."). Credits to Hannes Frederic Sowa who also had a hand in this as well. Also thanks to Hangbin Liu who did initial testing. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: David Stevens <dlstevens@us.ibm.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-20net: ipv6: mcast: minor: use defines for rfc3810/8.1 lengthsDaniel Borkmann1-3/+6
Instead of hard-coding length values, use a define to make it clear where those lengths come from. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-20net: ipv6: minor: *_start_timer: rather use unsigned longDaniel Borkmann1-5/+5
For the functions mld_gq_start_timer(), mld_ifc_start_timer(), and mld_dad_start_timer(), rather use unsigned long than int as we operate only on unsigned values anyway. This seems more appropriate as there is no good reason to do type conversions to int, that could lead to future errors. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-20net: ipv6: igmp6_event_query: use msecs_to_jiffiesDaniel Borkmann1-6/+5
Use proper API functions to calculate jiffies from milliseconds and not the crude method of dividing HZ by a value. This ensures more accurate values even in the case of strange HZ values. While at it, also simplify code in the mlh2 case by using max(). Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>