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* net: diag: support v4mapped sockets in inet_diag_find_one_icsk()Eric Dumazet2020-01-111-6/+12
| | | | | | | | | | | | | | | commit 7c1306723ee916ea9f1fa7d9e4c7a6d029ca7aaf upstream. Lorenzo reported that we could not properly find v4mapped sockets in inet_diag_find_one_icsk(). This patch fixes the issue. Reported-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Arnd Bergmann <arnd@arndb.de> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp/dccp: drop SYN packets if accept queue is fullEric Dumazet2020-01-111-6/+1
| | | | | | | | | | | | | | | | | | | | | commit 5ea8ea2cb7f1d0db15762c9b0bb9e7330425a071 upstream. Per listen(fd, backlog) rules, there is really no point accepting a SYN, sending a SYNACK, and dropping the following ACK packet if accept queue is full, because application is not draining accept queue fast enough. This behavior is fooling TCP clients that believe they established a flow, while there is nothing at server side. They might then send about 10 MSS (if using IW10) that will be dropped anyway while server is under stress. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Arnd Bergmann <arnd@arndb.de> [bwh: Backported to 3.16: Apply TCP changes in both tcp_ipv4.c and tcp_ipv6.c] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* inet: stop leaking jiffies on the wireEric Dumazet2019-12-192-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a904a0693c189691eeee64f6c6b188bd7dc244e9 upstream. Historically linux tried to stick to RFC 791, 1122, 2003 for IPv4 ID field generation. RFC 6864 made clear that no matter how hard we try, we can not ensure unicity of IP ID within maximum lifetime for all datagrams with a given source address/destination address/protocol tuple. Linux uses a per socket inet generator (inet_id), initialized at connection startup with a XOR of 'jiffies' and other fields that appear clear on the wire. Thiemo Nagel pointed that this strategy is a privacy concern as this provides 16 bits of entropy to fingerprint devices. Let's switch to a random starting point, this is just as good as far as RFC 6864 is concerned and does not leak anything critical. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thiemo Nagel <tnagel@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: drop changes in chelsio] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net: ipv4: avoid mixed n_redirects and rate_tokens usagePaolo Abeni2019-12-191-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b406472b5ad79ede8d10077f0c8f05505ace8b6d upstream. 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> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net: ipv4: use a dedicated counter for icmp_v4 redirect packetsLorenzo Bianconi2019-12-192-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit c09551c6ff7fe16a79a42133bcecba5fc2fc3291 upstream. According to the algorithm described in the comment block at the beginning of ip_rt_send_redirect, the host should try to send 'ip_rt_redirect_number' ICMP redirect packets with an exponential backoff and then stop sending them at all assuming that the destination ignores redirects. If the device has previously sent some ICMP error packets that are rate-limited (e.g TTL expired) and continues to receive traffic, the redirect packets will never be transmitted. This happens since peer->rate_tokens will be typically greater than 'ip_rt_redirect_number' and so it will never be reset even if the redirect silence timeout (ip_rt_redirect_silence) has elapsed without receiving any packet requiring redirects. Fix it by using a dedicated counter for the number of ICMP redirect packets that has been sent by the host I have not been able to identify a given commit that introduced the issue since ip_rt_send_redirect implements the same rate-limiting algorithm from commit 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context, indentation] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: fix tcp_ecn_withdraw_cwr() to clear TCP_ECN_QUEUE_CWRNeal Cardwell2019-11-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit af38d07ed391b21f7405fa1f936ca9686787d6d2 upstream. Fix tcp_ecn_withdraw_cwr() to clear the correct bit: TCP_ECN_QUEUE_CWR. Rationale: basically, TCP_ECN_DEMAND_CWR is a bit that is purely about the behavior of data receivers, and deciding whether to reflect incoming IP ECN CE marks as outgoing TCP th->ece marks. The TCP_ECN_QUEUE_CWR bit is purely about the behavior of data senders, and deciding whether to send CWR. The tcp_ecn_withdraw_cwr() function is only called from tcp_undo_cwnd_reduction() by data senders during an undo, so it should zero the sender-side state, TCP_ECN_QUEUE_CWR. It does not make sense to stop the reflection of incoming CE bits on incoming data packets just because outgoing packets were spuriously retransmitted. The bug has been reproduced with packetdrill to manifest in a scenario with RFC3168 ECN, with an incoming data packet with CE bit set and carrying a TCP timestamp value that causes cwnd undo. Before this fix, the IP CE bit was ignored and not reflected in the TCP ECE header bit, and sender sent a TCP CWR ('W') bit on the next outgoing data packet, even though the cwnd reduction had been undone. After this fix, the sender properly reflects the CE bit and does not set the W bit. Note: the bug actually predates 2005 git history; this Fixes footer is chosen to be the oldest SHA1 I have tested (from Sep 2007) for which the patch applies cleanly (since before this commit the code was in a .h file). Fixes: bdf1ee5d3bd3 ("[TCP]: Move code from tcp_ecn.h to tcp*.c and tcp.h & remove it") Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* igmp: fix memory leak in igmpv3_del_delrec()Eric Dumazet2019-10-311-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e5b1c6c6277d5a283290a8c033c72544746f9b5b upstream. im->tomb and/or im->sources might not be NULL, but we currently overwrite their values blindly. Using swap() will make sure the following call to kfree_pmc(pmc) will properly free the psf structures. Tested with the C repro provided by syzbot, which basically does : socket(PF_INET, SOCK_DGRAM, IPPROTO_IP) = 3 setsockopt(3, SOL_IP, IP_ADD_MEMBERSHIP, "\340\0\0\2\177\0\0\1\0\0\0\0", 12) = 0 ioctl(3, SIOCSIFFLAGS, {ifr_name="lo", ifr_flags=0}) = 0 setsockopt(3, SOL_IP, IP_MSFILTER, "\340\0\0\2\177\0\0\1\1\0\0\0\1\0\0\0\377\377\377\377", 20) = 0 ioctl(3, SIOCSIFFLAGS, {ifr_name="lo", ifr_flags=IFF_UP}) = 0 exit_group(0) = ? BUG: memory leak unreferenced object 0xffff88811450f140 (size 64): comm "softirq", pid 0, jiffies 4294942448 (age 32.070s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 ff ff ff ff 00 00 00 00 ................ 00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................ backtrace: [<00000000c7bad083>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline] [<00000000c7bad083>] slab_post_alloc_hook mm/slab.h:439 [inline] [<00000000c7bad083>] slab_alloc mm/slab.c:3326 [inline] [<00000000c7bad083>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<000000009acc4151>] kmalloc include/linux/slab.h:547 [inline] [<000000009acc4151>] kzalloc include/linux/slab.h:742 [inline] [<000000009acc4151>] ip_mc_add1_src net/ipv4/igmp.c:1976 [inline] [<000000009acc4151>] ip_mc_add_src+0x36b/0x400 net/ipv4/igmp.c:2100 [<000000004ac14566>] ip_mc_msfilter+0x22d/0x310 net/ipv4/igmp.c:2484 [<0000000052d8f995>] do_ip_setsockopt.isra.0+0x1795/0x1930 net/ipv4/ip_sockglue.c:959 [<000000004ee1e21f>] ip_setsockopt+0x3b/0xb0 net/ipv4/ip_sockglue.c:1248 [<0000000066cdfe74>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2618 [<000000009383a786>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3126 [<00000000d8ac0c94>] __sys_setsockopt+0x98/0x120 net/socket.c:2072 [<000000001b1e9666>] __do_sys_setsockopt net/socket.c:2083 [inline] [<000000001b1e9666>] __se_sys_setsockopt net/socket.c:2080 [inline] [<000000001b1e9666>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2080 [<00000000420d395e>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301 [<000000007fd83a4b>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 24803f38a5c0 ("igmp: do not remove igmp souce list info when set link down") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hangbin Liu <liuhangbin@gmail.com> Reported-by: syzbot+6ca1abd0db68b5173a4f@syzkaller.appspotmail.com Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4/igmp: fix build error if !CONFIG_IP_MULTICASTEric Dumazet2019-10-051-11/+11
| | | | | | | | | | | | commit 903869bd10e6719b9df6718e785be7ec725df59f upstream. ip_sf_list_clear_all() needs to be defined even if !CONFIG_IP_MULTICAST Fixes: 3580d04aa674 ("ipv4/igmp: fix another memory leak in igmpv3_del_delrec()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4/igmp: fix another memory leak in igmpv3_del_delrec()Eric Dumazet2019-10-051-17/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3580d04aa674383c42de7b635d28e52a1e5bc72c upstream. syzbot reported memory leaks [1] that I have back tracked to a missing cleanup from igmpv3_del_delrec() when (im->sfmode != MCAST_INCLUDE) Add ip_sf_list_clear_all() and kfree_pmc() helpers to explicitely handle the cleanups before freeing. [1] BUG: memory leak unreferenced object 0xffff888123e32b00 (size 64): comm "softirq", pid 0, jiffies 4294942968 (age 8.010s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 e0 00 00 01 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000006105011b>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<000000006105011b>] slab_post_alloc_hook mm/slab.h:439 [inline] [<000000006105011b>] slab_alloc mm/slab.c:3326 [inline] [<000000006105011b>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<000000004bba8073>] kmalloc include/linux/slab.h:547 [inline] [<000000004bba8073>] kzalloc include/linux/slab.h:742 [inline] [<000000004bba8073>] ip_mc_add1_src net/ipv4/igmp.c:1961 [inline] [<000000004bba8073>] ip_mc_add_src+0x36b/0x400 net/ipv4/igmp.c:2085 [<00000000a46a65a0>] ip_mc_msfilter+0x22d/0x310 net/ipv4/igmp.c:2475 [<000000005956ca89>] do_ip_setsockopt.isra.0+0x1795/0x1930 net/ipv4/ip_sockglue.c:957 [<00000000848e2d2f>] ip_setsockopt+0x3b/0xb0 net/ipv4/ip_sockglue.c:1246 [<00000000b9db185c>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2616 [<000000003028e438>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130 [<0000000015b65589>] __sys_setsockopt+0x98/0x120 net/socket.c:2078 [<00000000ac198ef0>] __do_sys_setsockopt net/socket.c:2089 [inline] [<00000000ac198ef0>] __se_sys_setsockopt net/socket.c:2086 [inline] [<00000000ac198ef0>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086 [<000000000a770437>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301 [<00000000d3adb93b>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 9c8bb163ae78 ("igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hangbin Liu <liuhangbin@gmail.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* igmp: add a missing spin_lock_init()WANG Cong2019-10-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b4846fc3c8559649277e3e4e6b5cec5348a8d208 upstream. Andrey reported a lockdep warning on non-initialized spinlock: INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 1 PID: 4099 Comm: a.out Not tainted 4.12.0-rc6+ #9 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x292/0x395 lib/dump_stack.c:52 register_lock_class+0x717/0x1aa0 kernel/locking/lockdep.c:755 ? 0xffffffffa0000000 __lock_acquire+0x269/0x3690 kernel/locking/lockdep.c:3255 lock_acquire+0x22d/0x560 kernel/locking/lockdep.c:3855 __raw_spin_lock_bh ./include/linux/spinlock_api_smp.h:135 _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:175 spin_lock_bh ./include/linux/spinlock.h:304 ip_mc_clear_src+0x27/0x1e0 net/ipv4/igmp.c:2076 igmpv3_clear_delrec+0xee/0x4f0 net/ipv4/igmp.c:1194 ip_mc_destroy_dev+0x4e/0x190 net/ipv4/igmp.c:1736 We miss a spin_lock_init() in igmpv3_add_delrec(), probably because previously we never use it on this code path. Since we already unlink it from the global mc_tomb list, it is probably safe not to acquire this spinlock here. It does not harm to have it although, to avoid conditional locking. Fixes: c38b7d327aaf ("igmp: acquire pmc lock for ip_mc_clear_src()") Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* igmp: acquire pmc lock for ip_mc_clear_src()WANG Cong2019-10-051-8/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit c38b7d327aafd1e3ad7ff53eefac990673b65667 upstream. Andrey reported a use-after-free in add_grec(): for (psf = *psf_list; psf; psf = psf_next) { ... psf_next = psf->sf_next; where the struct ip_sf_list's were already freed by: kfree+0xe8/0x2b0 mm/slub.c:3882 ip_mc_clear_src+0x69/0x1c0 net/ipv4/igmp.c:2078 ip_mc_dec_group+0x19a/0x470 net/ipv4/igmp.c:1618 ip_mc_drop_socket+0x145/0x230 net/ipv4/igmp.c:2609 inet_release+0x4e/0x1c0 net/ipv4/af_inet.c:411 sock_release+0x8d/0x1e0 net/socket.c:597 sock_close+0x16/0x20 net/socket.c:1072 This happens because we don't hold pmc->lock in ip_mc_clear_src() and a parallel mr_ifc_timer timer could jump in and access them. The RCU lock is there but it is merely for pmc itself, this spinlock could actually ensure we don't access them in parallel. Thanks to Eric and Long for discussion on this bug. Reported-by: Andrey Konovalov <andreyknvl@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Xin Long <lucien.xin@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4: Use return value of inet_iif() for __raw_v4_lookup in the while loopStephen Suryaputra2019-09-231-1/+1
| | | | | | | | | | | | | | | | commit 38c73529de13e1e10914de7030b659a2f8b01c3b upstream. In commit 19e4e768064a8 ("ipv4: Fix raw socket lookup for local traffic"), the dif argument to __raw_v4_lookup() is coming from the returned value of inet_iif() but the change was done only for the first lookup. Subsequent lookups in the while loop still use skb->dev->ifIndex. Fixes: 19e4e768064a8 ("ipv4: Fix raw socket lookup for local traffic") Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4: Fix raw socket lookup for local trafficDavid Ahern2019-09-231-2/+2
| | | | | | | | | | | | | | | | | | | commit 19e4e768064a87b073a4b4c138b55db70e0cfb9f upstream. inet_iif should be used for the raw socket lookup. inet_iif considers rt_iif which handles the case of local traffic. As it stands, ping to a local address with the '-I <dev>' option fails ever since ping was changed to use SO_BINDTODEVICE instead of cmsg + IP_PKTINFO. IPv6 works fine. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* inet: switch IP ID generator to siphashEric Dumazet2019-08-131-5/+7
| | | | | | | | | | | | | | | | | | | commit df453700e8d81b1bdafdf684365ee2b9431fb702 upstream. 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> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4: ip_tunnel: use net namespace from rtable not socketHannes Frederic Sowa2019-08-131-1/+2
| | | | | | | | | | | | | | | | commit 926a882f6916fd76b6f8ee858d45a2241c5e7999 upstream. The socket parameter might legally be NULL, thus sock_net is sometimes causing a NULL pointer dereference. Using net_device pointer in dst_entry is more reliable. Fixes: b6a7719aedd7e5c ("ipv4: hash net ptr into fragmentation bucket selection") Reported-by: Rick Jones <rick.jones2@hp.com> Cc: Rick Jones <rick.jones2@hp.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4: hash net ptr into fragmentation bucket selectionHannes Frederic Sowa2019-08-137-13/+15
| | | | | | | | | | | | | | | commit b6a7719aedd7e5c0f2df7641aa47386111682df4 upstream. As namespaces are sometimes used with overlapping ip address ranges, we should also use the namespace as input to the hash to select the ip fragmentation counter bucket. Cc: Eric Dumazet <edumazet@google.com> Cc: Flavio Leitner <fbl@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* Revert "inet: update the IP ID generation algorithm to higher standards."Ben Hutchings2019-08-131-3/+1
| | | | | | | | This reverts commit 8b197d3ce585d6777197e0633d71e5af7d98cb35, which was a stable-specific improvement to IP ID selection. I will apply the upstream changes instead. Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xfrm4: Fix uninitialized memory read in _decode_session4Steffen Klassert2019-08-131-11/+13
| | | | | | | | | | | | | | | commit 8742dc86d0c7a9628117a989c11f04a9b6b898f3 upstream. We currently don't reload pointers pointing into skb header after doing pskb_may_pull() in _decode_session4(). So in case pskb_may_pull() changed the pointers, we read from random memory. Fix this by putting all the needed infos on the stack, so that we don't need to access the header pointers after doing pskb_may_pull(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xfrm4: Reload skb header pointers after calling pskb_may_pull.Steffen Klassert2019-08-131-7/+26
| | | | | | | | | | commit ea673a4d3a337184f3c314dcc6300bf02f39e077 upstream. A call to pskb_may_pull may change the pointers into the packet, so reload the pointers after the call. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xfrm4: Fix header checks in _decode_session4.Steffen Klassert2019-08-131-5/+10
| | | | | | | | | | | | | | | commit 1a14f1e5550a341f76e5c8f596e9b5f8a886dfbc upstream. We skip the header informations if the data pointer points already behind the header in question for some protocols. This is because we call pskb_may_pull with a negative value converted to unsigened int from pskb_may_pull in this case. Skipping the header informations can lead to incorrect policy lookups, so fix it by a check of the data pointer position before we call pskb_may_pull. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: refine memory limit test in tcp_fragment()Eric Dumazet2019-07-091-1/+1
| | | | | | | | | | | | | | | | | | | | commit b6653b3629e5b88202be3c9abc44713973f5c4b4 upstream. tcp_fragment() might be called for skbs in the write queue. Memory limits might have been exceeded because tcp_sendmsg() only checks limits at full skb (64KB) boundaries. Therefore, we need to make sure tcp_fragment() wont punish applications that might have setup very low SO_SNDBUF values. Fixes: f070ef2ac667 ("tcp: tcp_fragment() should apply sane memory limits") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Christoph Paasch <cpaasch@apple.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* route: set the deleted fnhe fnhe_daddr to 0 in ip_del_fnhe to fix a raceXin Long2019-07-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ee60ad219f5c7c4fb2f047f88037770063ef785f upstream. 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> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: enforce tcp_min_snd_mss in tcp_mtu_probing()Eric Dumazet2019-06-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | commit 967c05aee439e6e5d7d805e195b3a20ef5c433d6 upstream. If mtu probing is enabled tcp_mtu_probing() could very well end up with a too small MSS. Use the new sysctl tcp_min_snd_mss to make sure MSS search is performed in an acceptable range. CVE-2019-11479 -- tcp mss hardcoded to 48 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Lemon <jonathan.lemon@gmail.com> Cc: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Bruce Curtis <brucec@netflix.com> Signed-off-by: David S. Miller <davem@davemloft.net> [Salvatore Bonaccorso: Backport for context changes in 4.9.168] [bwh: Backported to 3.16: The sysctl is global] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: add tcp_min_snd_mss sysctlEric Dumazet2019-06-202-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5f3e2bf008c2221478101ee72f5cb4654b9fc363 upstream. Some TCP peers announce a very small MSS option in their SYN and/or SYN/ACK messages. This forces the stack to send packets with a very high network/cpu overhead. Linux has enforced a minimal value of 48. Since this value includes the size of TCP options, and that the options can consume up to 40 bytes, this means that each segment can include only 8 bytes of payload. In some cases, it can be useful to increase the minimal value to a saner value. We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility reasons. Note that TCP_MAXSEG socket option enforces a minimal value of (TCP_MIN_MSS). David Miller increased this minimal value in commit c39508d6f118 ("tcp: Make TCP_MAXSEG minimum more correct.") from 64 to 88. We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS. CVE-2019-11479 -- tcp mss hardcoded to 48 Signed-off-by: Eric Dumazet <edumazet@google.com> Suggested-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [Salvatore Bonaccorso: Backport for context changes in 4.9.168] [bwh: Backported to 3.16: Make the sysctl global, consistent with net.ipv4.tcp_base_mss] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: tcp_fragment() should apply sane memory limitsEric Dumazet2019-06-202-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f070ef2ac66716357066b683fb0baf55f8191a2e upstream. Jonathan Looney reported that a malicious peer can force a sender to fragment its retransmit queue into tiny skbs, inflating memory usage and/or overflow 32bit counters. TCP allows an application to queue up to sk_sndbuf bytes, so we need to give some allowance for non malicious splitting of retransmit queue. A new SNMP counter is added to monitor how many times TCP did not allow to split an skb if the allowance was exceeded. Note that this counter might increase in the case applications use SO_SNDBUF socket option to lower sk_sndbuf. CVE-2019-11478 : tcp_fragment, prevent fragmenting a packet when the socket is already using more than half the allowed space Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [Salvatore Bonaccorso: Adjust context for backport to 4.9.168] [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: limit payload size of sacked skbsEric Dumazet2019-06-203-7/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3b4929f65b0d8249f19a50245cd88ed1a2f78cff upstream. Jonathan Looney reported that TCP can trigger the following crash in tcp_shifted_skb() : BUG_ON(tcp_skb_pcount(skb) < pcount); This can happen if the remote peer has advertized the smallest MSS that linux TCP accepts : 48 An skb can hold 17 fragments, and each fragment can hold 32KB on x86, or 64KB on PowerPC. This means that the 16bit witdh of TCP_SKB_CB(skb)->tcp_gso_segs can overflow. Note that tcp_sendmsg() builds skbs with less than 64KB of payload, so this problem needs SACK to be enabled. SACK blocks allow TCP to coalesce multiple skbs in the retransmit queue, thus filling the 17 fragments to maximal capacity. CVE-2019-11477 -- u16 overflow of TCP_SKB_CB(skb)->tcp_gso_segs Backport notes, provided by Joao Martins <joao.m.martins@oracle.com> v4.15 or since commit 737ff314563 ("tcp: use sequence distance to detect reordering") had switched from the packet-based FACK tracking and switched to sequence-based. v4.14 and older still have the old logic and hence on tcp_skb_shift_data() needs to retain its original logic and have @fack_count in sync. In other words, we keep the increment of pcount with tcp_skb_pcount(skb) to later used that to update fack_count. To make it more explicit we track the new skb that gets incremented to pcount in @next_pcount, and we get to avoid the constant invocation of tcp_skb_pcount(skb) all together. Fixes: 832d11c5cd07 ("tcp: Try to restore large SKBs while SACK processing") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [Salvatore Bonaccorso: Adjust for context changes to backport to 4.9.168] [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4: fix a race in update_or_create_fnhe()Eric Dumazet2019-05-112-6/+8
| | | | | | | | | | | | | commit caa415270c732505240bb60171c44a7838c555e8 upstream. nh_exceptions is effectively used under rcu, but lacks proper barriers. Between kzalloc() and setting of nh->nh_exceptions(), we need a proper memory barrier. Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: 4895c771c7f00 ("ipv4: Add FIB nexthop exceptions.") Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* inet: update the IP ID generation algorithm to higher standards.Amit Klein2019-05-111-1/+3
| | | | | | | | | | | | | | | | | Commit 355b98553789 ("netns: provide pure entropy for net_hash_mix()") makes net_hash_mix() return a true 32 bits of entropy. When used in the IP ID generation algorithm, this has the effect of extending the IP ID generation key from 32 bits to 64 bits. However, net_hash_mix() is only used for IP ID generation starting with kernel version 4.1. Therefore, earlier kernels remain with 32-bit key no matter what the net_hash_mix() return value is. This change addresses the issue by explicitly extending the key to 64 bits for kernels older than 4.1. Signed-off-by: Amit Klein <aksecurity@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* netlabel: fix out-of-bounds memory accessesPaul Moore2019-05-021-2/+4
| | | | | | | | | | | | | | | | | | | | | commit 5578de4834fe0f2a34fedc7374be691443396d1f upstream. There are two array out-of-bounds memory accesses, one in cipso_v4_map_lvl_valid(), the other in netlbl_bitmap_walk(). Both errors are embarassingly simple, and the fixes are straightforward. As a FYI for anyone backporting this patch to kernels prior to v4.8, you'll want to apply the netlbl_bitmap_walk() patch to cipso_v4_bitmap_walk() as netlbl_bitmap_walk() doesn't exist before Linux v4.8. Reported-by: Jann Horn <jannh@google.com> Fixes: 446fda4f2682 ("[NetLabel]: CIPSOv4 engine") Fixes: 3faa8f982f95 ("netlabel: Move bitmap manipulation functions to the NetLabel core.") Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16 following Paul's hint] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net/ipv4: defensive cipso option parsingStefan Nuernberger2019-02-111-4/+7
| | | | | | | | | | | | | | | | | | | | | commit 076ed3da0c9b2f88d9157dbe7044a45641ae369e upstream. commit 40413955ee26 ("Cipso: cipso_v4_optptr enter infinite loop") fixed a possible infinite loop in the IP option parsing of CIPSO. The fix assumes that ip_options_compile filtered out all zero length options and that no other one-byte options beside IPOPT_END and IPOPT_NOOP exist. While this assumption currently holds true, add explicit checks for zero length and invalid length options to be safe for the future. Even though ip_options_compile should have validated the options, the introduction of new one-byte options can still confuse this code without the additional checks. Signed-off-by: Stefan Nuernberger <snu@amazon.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Simon Veith <sveith@amazon.de> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* Cipso: cipso_v4_optptr enter infinite loopyujuan.qi2019-02-111-2/+10
| | | | | | | | | | | | | commit 40413955ee265a5e42f710940ec78f5450d49149 upstream. in for(),if((optlen > 0) && (optptr[1] == 0)), enter infinite loop. Test: receive a packet which the ip length > 20 and the first byte of ip option is 0, produce this issue Signed-off-by: yujuan.qi <yujuan.qi@mediatek.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* cipso: don't use IPCB() to locate the CIPSO IP optionPaul Moore2019-02-111-21/+30
| | | | | | | | | | | | | | | | | | | | | | | commit 04f81f0154e4bf002be6f4d85668ce1257efa4d9 upstream. Using the IPCB() macro to get the IPv4 options is convenient, but unfortunately NetLabel often needs to examine the CIPSO option outside of the scope of the IP layer in the stack. While historically IPCB() worked above the IP layer, due to the inclusion of the inet_skb_param struct at the head of the {tcp,udp}_skb_cb structs, recent commit 971f10ec ("tcp: better TCP_SKB_CB layout to reduce cache line misses") reordered the tcp_skb_cb struct and invalidated this IPCB() trick. This patch fixes the problem by creating a new function, cipso_v4_optptr(), which locates the CIPSO option inside the IP header without calling IPCB(). Unfortunately, this isn't as fast as a simple lookup so some additional tweaks were made to limit the use of this new function. Reported-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <pmoore@redhat.com> Tested-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net: ipv4: update fnhe_pmtu when first hop's MTU changesSabrina Dubroca2018-12-162-0/+54
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit af7d6cce53694a88d6a1bb60c9a239a6a5144459 upstream. Since commit 5aad1de5ea2c ("ipv4: use separate genid for next hop exceptions"), exceptions get deprecated separately from cached routes. In particular, administrative changes don't clear PMTU anymore. As Stefano described in commit e9fa1495d738 ("ipv6: Reflect MTU changes on PMTU of exceptions for MTU-less routes"), the PMTU discovered before the local MTU change can become stale: - if the local MTU is now lower than the PMTU, that PMTU is now incorrect - if the local MTU was the lowest value in the path, and is increased, we might discover a higher PMTU Similarly to what commit e9fa1495d738 did for IPv6, update PMTU in those cases. If the exception was locked, the discovered PMTU was smaller than the minimal accepted PMTU. In that case, if the new local MTU is smaller than the current PMTU, let PMTU discovery figure out if locking of the exception is still needed. To do this, we need to know the old link MTU in the NETDEV_CHANGEMTU notifier. By the time the notifier is called, dev->mtu has been changed. This patch adds the old MTU as additional information in the notifier structure, and a new call_netdevice_notifiers_u32() function. Fixes: 5aad1de5ea2c ("ipv4: use separate genid for next hop exceptions") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: - Pass net_device argument to call_netdevice_notifiers_info() - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip_tunnel: be careful when accessing the inner headerPaolo Abeni2018-12-161-0/+9
| | | | | | | | | | | | | | commit ccfec9e5cb2d48df5a955b7bf47f7782157d3bc2 upstream. Cong noted that we need the same checks introduced by commit 76c0ddd8c3a6 ("ip6_tunnel: be careful when accessing the inner header") even for ipv4 tunnels. Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.") Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* igmp: fix incorrect unsolicit report count after link down and upHangbin Liu2018-12-161-1/+2
| | | | | | | | | | | | | | | | | | | commit ff06525fcb8ae3c302ac1319bf6c07c026dea964 upstream. After link down and up, i.e. when call ip_mc_up(), we doesn't init im->unsolicit_count. So after igmp_timer_expire(), we will not start timer again and only send one unsolicit report at last. Fix it by initializing im->unsolicit_count in igmp_group_added(), so we can respect igmp robustness value. Fixes: 24803f38a5c0b ("igmp: do not remove igmp souce list info when set link down") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: - Keep using constant IGMP_Unsolicited_Report_Count - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* igmp: fix incorrect unsolicit report count when join groupHangbin Liu2018-12-161-3/+2
| | | | | | | | | | | | | commit 4fb7253e4f9a8f06a986a3b317e2f79d9b43d552 upstream. We should not start timer if im->unsolicit_count equal to 0 after decrease. Or we will send one more unsolicit report message. i.e. 3 instead of 2 by default. Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4: remove BUG_ON() from fib_compute_spec_dstLorenzo Bianconi2018-11-201-2/+3
| | | | | | | | | | | | | | | | | commit 9fc12023d6f51551d6ca9ed7e02ecc19d79caf17 upstream. Remove BUG_ON() from fib_compute_spec_dst routine and check in_dev pointer during flowi4 data structure initialization. fib_compute_spec_dst routine can be run concurrently with device removal where ip_ptr net_device pointer is set to NULL. This can happen if userspace enables pkt info on UDP rx socket and the device is removed while traffic is flowing Fixes: 35ebf65e851c ("ipv4: Create and use fib_compute_spec_dst() helper") Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* multicast: do not restore deleted record source filter mode to new oneHangbin Liu2018-11-201-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | commit 08d3ffcc0cfaba36f6b86fd568cc3bc773061fa6 upstream. There are two scenarios that we will restore deleted records. The first is when device down and up(or unmap/remap). In this scenario the new filter mode is same with previous one. Because we get it from in_dev->mc_list and we do not touch it during device down and up. The other scenario is when a new socket join a group which was just delete and not finish sending status reports. In this scenario, we should use the current filter mode instead of restore old one. Here are 4 cases in total. old_socket new_socket before_fix after_fix IN(A) IN(A) ALLOW(A) ALLOW(A) IN(A) EX( ) TO_IN( ) TO_EX( ) EX( ) IN(A) TO_EX( ) ALLOW(A) EX( ) EX( ) TO_EX( ) TO_EX( ) Fixes: 24803f38a5c0b (igmp: do not remove igmp souce list info when set link down) Fixes: 1666d49e1d416 (mld: do not remove mld souce list info when set link down) Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net: metrics: add proper netlink validationEric Dumazet2018-11-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5b5e7a0de2bbf2a1afcd9f49e940010e9fb80d53 upstream. Before using nla_get_u32(), better make sure the attribute is of the proper size. Code recently was changed, but bug has been there from beginning of git. BUG: KMSAN: uninit-value in rtnetlink_put_metrics+0x553/0x960 net/core/rtnetlink.c:746 CPU: 1 PID: 14139 Comm: syz-executor6 Not tainted 4.17.0-rc5+ #103 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+0x185/0x1d0 lib/dump_stack.c:113 kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084 __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:686 rtnetlink_put_metrics+0x553/0x960 net/core/rtnetlink.c:746 fib_dump_info+0xc42/0x2190 net/ipv4/fib_semantics.c:1361 rtmsg_fib+0x65f/0x8c0 net/ipv4/fib_semantics.c:419 fib_table_insert+0x2314/0x2b50 net/ipv4/fib_trie.c:1287 inet_rtm_newroute+0x210/0x340 net/ipv4/fib_frontend.c:779 rtnetlink_rcv_msg+0xa32/0x1560 net/core/rtnetlink.c:4646 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2448 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4664 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x1678/0x1750 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg net/socket.c:639 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117 __sys_sendmsg net/socket.c:2155 [inline] __do_sys_sendmsg net/socket.c:2164 [inline] __se_sys_sendmsg net/socket.c:2162 [inline] __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x455a09 RSP: 002b:00007faae5fd8c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007faae5fd96d4 RCX: 0000000000455a09 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000005d0 R14: 00000000006fdc20 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline] kmsan_save_stack mm/kmsan/kmsan.c:294 [inline] kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:685 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:529 fib_convert_metrics net/ipv4/fib_semantics.c:1056 [inline] fib_create_info+0x2d46/0x9dc0 net/ipv4/fib_semantics.c:1150 fib_table_insert+0x3e4/0x2b50 net/ipv4/fib_trie.c:1146 inet_rtm_newroute+0x210/0x340 net/ipv4/fib_frontend.c:779 rtnetlink_rcv_msg+0xa32/0x1560 net/core/rtnetlink.c:4646 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2448 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4664 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x1678/0x1750 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg net/socket.c:639 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117 __sys_sendmsg net/socket.c:2155 [inline] __do_sys_sendmsg net/socket.c:2164 [inline] __se_sys_sendmsg net/socket.c:2162 [inline] __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:189 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:315 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan.c:322 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2753 [inline] __kmalloc_node_track_caller+0xb32/0x11b0 mm/slub.c:4395 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:988 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline] netlink_sendmsg+0x76e/0x1350 net/netlink/af_netlink.c:1876 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg net/socket.c:639 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117 __sys_sendmsg net/socket.c:2155 [inline] __do_sys_sendmsg net/socket.c:2164 [inline] __se_sys_sendmsg net/socket.c:2162 [inline] __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: a919525ad832 ("net: Move fib_convert_metrics to metrics file") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: Metrics are parsed in fib_create_info()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip_tunnel: restore binding to ifaces with a large mtuNicolas Dichtel2018-10-211-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 82612de1c98e610d194e34178bde3cca7dedce41 upstream. After commit f6cc9c054e77, the following conf is broken (note that the default loopback mtu is 65536, ie IP_MAX_MTU + 1): $ ip tunnel add gre1 mode gre local 10.125.0.1 remote 10.125.0.2 dev lo add tunnel "gre0" failed: Invalid argument $ ip l a type dummy $ ip l s dummy1 up $ ip l s dummy1 mtu 65535 $ ip tunnel add gre1 mode gre local 10.125.0.1 remote 10.125.0.2 dev dummy1 add tunnel "gre0" failed: Invalid argument dev_set_mtu() doesn't allow to set a mtu which is too large. First, let's cap the mtu returned by ip_tunnel_bind_dev(). Second, remove the magic value 0xFFF8 and use IP_MAX_MTU instead. 0xFFF8 seems to be there for ages, I don't know why this value was used. With a recent kernel, it's also possible to set a mtu > IP_MAX_MTU: $ ip l s dummy1 mtu 66000 After that patch, it's also possible to bind an ip tunnel on that kind of interface. CC: Petr Machata <petrm@mellanox.com> CC: Ido Schimmel <idosch@mellanox.com> Link: https://git.kernel.org/pub/scm/linux/kernel/git/davem/netdev-vger-cvs.git/commit/?id=e5afd356a411a Fixes: f6cc9c054e77 ("ip_tunnel: Emit events for post-register MTU changes") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: - Drop change in ip_tunnel_create() - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net: test tailroom before appending to linear skbWillem de Bruijn2018-10-211-1/+2
| | | | | | | | | | | | | | | | | | | | | commit 113f99c3358564a0647d444c2ae34e8b1abfd5b9 upstream. Device features may change during transmission. In particular with corking, a device may toggle scatter-gather in between allocating and writing to an skb. Do not unconditionally assume that !NETIF_F_SG at write time implies that the same held at alloc time and thus the skb has sufficient tailroom. This issue predates git history. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: purge write queue in tcp_connect_init()Eric Dumazet2018-10-211-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7f582b248d0a86bae5788c548d7bb5bca6f7691a upstream. syzkaller found a reliable way to crash the host, hitting a BUG() in __tcp_retransmit_skb() Malicous MSG_FASTOPEN is the root cause. We need to purge write queue in tcp_connect_init() at the point we init snd_una/write_seq. This patch also replaces the BUG() by a less intrusive WARN_ON_ONCE() kernel BUG at net/ipv4/tcp_output.c:2837! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 0 PID: 5276 Comm: syz-executor0 Not tainted 4.17.0-rc3+ #51 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__tcp_retransmit_skb+0x2992/0x2eb0 net/ipv4/tcp_output.c:2837 RSP: 0000:ffff8801dae06ff8 EFLAGS: 00010206 RAX: ffff8801b9fe61c0 RBX: 00000000ffc18a16 RCX: ffffffff864e1a49 RDX: 0000000000000100 RSI: ffffffff864e2e12 RDI: 0000000000000005 RBP: ffff8801dae073a0 R08: ffff8801b9fe61c0 R09: ffffed0039c40dd2 R10: ffffed0039c40dd2 R11: ffff8801ce206e93 R12: 00000000421eeaad R13: ffff8801ce206d4e R14: ffff8801ce206cc0 R15: ffff8801cd4f4a80 FS: 0000000000000000(0000) GS:ffff8801dae00000(0063) knlGS:00000000096bc900 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000020000000 CR3: 00000001c47b6000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> tcp_retransmit_skb+0x2e/0x250 net/ipv4/tcp_output.c:2923 tcp_retransmit_timer+0xc50/0x3060 net/ipv4/tcp_timer.c:488 tcp_write_timer_handler+0x339/0x960 net/ipv4/tcp_timer.c:573 tcp_write_timer+0x111/0x1d0 net/ipv4/tcp_timer.c:593 call_timer_fn+0x230/0x940 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x79e/0xc50 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1d1/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:525 [inline] smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 Fixes: cf60af03ca4e ("net-tcp: Fast Open client - sendmsg(MSG_FASTOPEN)") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4: fix memory leaks in udp_sendmsg, ping_v4_sendmsgAndrey Ignatov2018-10-212-4/+10
| | | | | | | | | | | | | | | | | | | | | | commit 1b97013bfb11d66f041de691de6f0fec748ce016 upstream. Fix more memory leaks in ip_cmsg_send() callers. Part of them were fixed earlier in 919483096bfe. * udp_sendmsg one was there since the beginning when linux sources were first added to git; * ping_v4_sendmsg one was copy/pasted in c319b4d76b9e. Whenever return happens in udp_sendmsg() or ping_v4_sendmsg() IP options have to be freed if they were allocated previously. Add label so that future callers (if any) can use it instead of kfree() before return that is easy to forget. Fixes: c319b4d76b9e (net: ipv4: add IPPROTO_ICMP socket kind) Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv4: fix fnhe usage by non-cached routesJulian Anastasov2018-10-211-65/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 94720e3aee6884d8c8beb678001629da60ec6366 upstream. Allow some non-cached routes to use non-expired fnhe: 1. ip_del_fnhe: moved above and now called by find_exception. The 4.5+ commit deed49df7390 expires fnhe only when caching routes. Change that to: 1.1. use fnhe for non-cached local output routes, with the help from (2) 1.2. allow __mkroute_input to detect expired fnhe (outdated fnhe_gw, for example) when do_cache is false, eg. when itag!=0 for unicast destinations. 2. __mkroute_output: keep fi to allow local routes with orig_oif != 0 to use fnhe info even when the new route will not be cached into fnhe. After commit 839da4d98960 ("net: ipv4: set orig_oif based on fib result for local traffic") it means all local routes will be affected because they are not cached. This change is used to solve a PMTU problem with IPVS (and probably Netfilter DNAT) setups that redirect local clients from target local IP (local route to Virtual IP) to new remote IP target, eg. IPVS TUN real server. Loopback has 64K MTU and we need to create fnhe on the local route that will keep the reduced PMTU for the Virtual IP. Without this change fnhe_pmtu is updated from ICMP but never exposed to non-cached local routes. This includes routes with flowi4_oif!=0 for 4.6+ and with flowi4_oif=any for 4.14+). 3. update_or_create_fnhe: make sure fnhe_expires is not 0 for new entries Fixes: 839da4d98960 ("net: ipv4: set orig_oif based on fib result for local traffic") Fixes: d6d5e999e5df ("route: do not cache fib route info on local routes with oif") Fixes: deed49df7390 ("route: check and remove route cache when we get route") Cc: David Ahern <dsahern@gmail.com> Cc: Xin Long <lucien.xin@gmail.com> Signed-off-by: Julian Anastasov <ja@ssi.bg> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: fix TCP_REPAIR_QUEUE bound checkingEric Dumazet2018-10-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit bf2acc943a45d2b2e8a9f1a5ddff6b6e43cc69d9 upstream. syzbot is able to produce a nasty WARN_ON() in tcp_verify_left_out() with following C-repro : socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 3 setsockopt(3, SOL_TCP, TCP_REPAIR, [1], 4) = 0 setsockopt(3, SOL_TCP, TCP_REPAIR_QUEUE, [-1], 4) = 0 bind(3, {sa_family=AF_INET, sin_port=htons(20002), sin_addr=inet_addr("0.0.0.0")}, 16) = 0 sendto(3, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 1242, MSG_FASTOPEN, {sa_family=AF_INET, sin_port=htons(20002), sin_addr=inet_addr("127.0.0.1")}, 16) = 1242 setsockopt(3, SOL_TCP, TCP_REPAIR_WINDOW, "\4\0\0@+\205\0\0\377\377\0\0\377\377\377\177\0\0\0\0", 20) = 0 writev(3, [{"\270", 1}], 1) = 1 setsockopt(3, SOL_TCP, TCP_REPAIR_OPTIONS, "\10\0\0\0\0\0\0\0\0\0\0\0|\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 386) = 0 writev(3, [{"\210v\r[\226\320t\231qwQ\204\264l\254\t\1\20\245\214p\350H\223\254;\\\37\345\307p$"..., 3144}], 1) = 3144 The 3rd system call looks odd : setsockopt(3, SOL_TCP, TCP_REPAIR_QUEUE, [-1], 4) = 0 This patch makes sure bound checking is using an unsigned compare. Fixes: ee9952831cfd ("tcp: Initial repair mode") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: don't read out-of-bounds opsizeJann Horn2018-10-211-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7e5a206ab686f098367b61aca989f5cdfa8114a3 upstream. The old code reads the "opsize" variable from out-of-bounds memory (first byte behind the segment) if a broken TCP segment ends directly after an opcode that is neither EOL nor NOP. The result of the read isn't used for anything, so the worst thing that could theoretically happen is a pagefault; and since the physmap is usually mostly contiguous, even that seems pretty unlikely. The following C reproducer triggers the uninitialized read - however, you can't actually see anything happen unless you put something like a pr_warn() in tcp_parse_md5sig_option() to print the opsize. ==================================== #define _GNU_SOURCE #include <arpa/inet.h> #include <stdlib.h> #include <errno.h> #include <stdarg.h> #include <net/if.h> #include <linux/if.h> #include <linux/ip.h> #include <linux/tcp.h> #include <linux/in.h> #include <linux/if_tun.h> #include <err.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <string.h> #include <stdio.h> #include <unistd.h> #include <sys/ioctl.h> #include <assert.h> void systemf(const char *command, ...) { char *full_command; va_list ap; va_start(ap, command); if (vasprintf(&full_command, command, ap) == -1) err(1, "vasprintf"); va_end(ap); printf("systemf: <<<%s>>>\n", full_command); system(full_command); } char *devname; int tun_alloc(char *name) { int fd = open("/dev/net/tun", O_RDWR); if (fd == -1) err(1, "open tun dev"); static struct ifreq req = { .ifr_flags = IFF_TUN|IFF_NO_PI }; strcpy(req.ifr_name, name); if (ioctl(fd, TUNSETIFF, &req)) err(1, "TUNSETIFF"); devname = req.ifr_name; printf("device name: %s\n", devname); return fd; } #define IPADDR(a,b,c,d) (((a)<<0)+((b)<<8)+((c)<<16)+((d)<<24)) void sum_accumulate(unsigned int *sum, void *data, int len) { assert((len&2)==0); for (int i=0; i<len/2; i++) { *sum += ntohs(((unsigned short *)data)[i]); } } unsigned short sum_final(unsigned int sum) { sum = (sum >> 16) + (sum & 0xffff); sum = (sum >> 16) + (sum & 0xffff); return htons(~sum); } void fix_ip_sum(struct iphdr *ip) { unsigned int sum = 0; sum_accumulate(&sum, ip, sizeof(*ip)); ip->check = sum_final(sum); } void fix_tcp_sum(struct iphdr *ip, struct tcphdr *tcp) { unsigned int sum = 0; struct { unsigned int saddr; unsigned int daddr; unsigned char pad; unsigned char proto_num; unsigned short tcp_len; } fakehdr = { .saddr = ip->saddr, .daddr = ip->daddr, .proto_num = ip->protocol, .tcp_len = htons(ntohs(ip->tot_len) - ip->ihl*4) }; sum_accumulate(&sum, &fakehdr, sizeof(fakehdr)); sum_accumulate(&sum, tcp, tcp->doff*4); tcp->check = sum_final(sum); } int main(void) { int tun_fd = tun_alloc("inject_dev%d"); systemf("ip link set %s up", devname); systemf("ip addr add 192.168.42.1/24 dev %s", devname); struct { struct iphdr ip; struct tcphdr tcp; unsigned char tcp_opts[20]; } __attribute__((packed)) syn_packet = { .ip = { .ihl = sizeof(struct iphdr)/4, .version = 4, .tot_len = htons(sizeof(syn_packet)), .ttl = 30, .protocol = IPPROTO_TCP, /* FIXUP check */ .saddr = IPADDR(192,168,42,2), .daddr = IPADDR(192,168,42,1) }, .tcp = { .source = htons(1), .dest = htons(1337), .seq = 0x12345678, .doff = (sizeof(syn_packet.tcp)+sizeof(syn_packet.tcp_opts))/4, .syn = 1, .window = htons(64), .check = 0 /*FIXUP*/ }, .tcp_opts = { /* INVALID: trailing MD5SIG opcode after NOPs */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 19 } }; fix_ip_sum(&syn_packet.ip); fix_tcp_sum(&syn_packet.ip, &syn_packet.tcp); while (1) { int write_res = write(tun_fd, &syn_packet, sizeof(syn_packet)); if (write_res != sizeof(syn_packet)) err(1, "packet write failed"); } } ==================================== Fixes: cfb6eeb4c860 ("[TCP]: MD5 Signature Option (RFC2385) support.") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established socketsEric Dumazet2018-10-211-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7212303268918b9a203aebeacfdbd83b5e87b20d upstream. syzbot/KMSAN reported an uninit-value in tcp_parse_options() [1] I believe this was caused by a TCP_MD5SIG being set on live flow. This is highly unexpected, since TCP option space is limited. For instance, presence of TCP MD5 option automatically disables TCP TimeStamp option at SYN/SYNACK time, which we can not do once flow has been established. Really, adding/deleting an MD5 key only makes sense on sockets in CLOSE or LISTEN state. [1] BUG: KMSAN: uninit-value in tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720 CPU: 1 PID: 6177 Comm: syzkaller192004 Not tainted 4.16.0+ #83 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720 tcp_fast_parse_options net/ipv4/tcp_input.c:3858 [inline] tcp_validate_incoming+0x4f1/0x2790 net/ipv4/tcp_input.c:5184 tcp_rcv_established+0xf60/0x2bb0 net/ipv4/tcp_input.c:5453 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x2d6/0x680 net/core/sock.c:2271 release_sock+0x97/0x2a0 net/core/sock.c:2786 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747 SyS_sendto+0x8a/0xb0 net/socket.c:1715 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x448fe9 RSP: 002b:00007fd472c64d38 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000006e5a30 RCX: 0000000000448fe9 RDX: 000000000000029f RSI: 0000000020a88f88 RDI: 0000000000000004 RBP: 00000000006e5a34 R08: 0000000020e68000 R09: 0000000000000010 R10: 00000000200007fd R11: 0000000000000216 R12: 0000000000000000 R13: 00007fff074899ef R14: 00007fd472c659c0 R15: 0000000000000009 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slub.c:2737 [inline] __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:984 [inline] tcp_send_ack+0x18c/0x910 net/ipv4/tcp_output.c:3624 __tcp_ack_snd_check net/ipv4/tcp_input.c:5040 [inline] tcp_ack_snd_check net/ipv4/tcp_input.c:5053 [inline] tcp_rcv_established+0x2103/0x2bb0 net/ipv4/tcp_input.c:5469 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x2d6/0x680 net/core/sock.c:2271 release_sock+0x97/0x2a0 net/core/sock.c:2786 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747 SyS_sendto+0x8a/0xb0 net/socket.c:1715 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Fixes: cfb6eeb4c860 ("[TCP]: MD5 Signature Option (RFC2385) support.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* soreuseport: initialise timewait reuseport fieldEric Dumazet2018-10-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3099a52918937ab86ec47038ad80d377ba16c531 upstream. syzbot reported an uninit-value in inet_csk_bind_conflict() [1] It turns out we never propagated sk->sk_reuseport into timewait socket. [1] BUG: KMSAN: uninit-value in inet_csk_bind_conflict+0x5f9/0x990 net/ipv4/inet_connection_sock.c:151 CPU: 1 PID: 3589 Comm: syzkaller008242 Not tainted 4.16.0+ #82 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 inet_csk_bind_conflict+0x5f9/0x990 net/ipv4/inet_connection_sock.c:151 inet_csk_get_port+0x1d28/0x1e40 net/ipv4/inet_connection_sock.c:320 inet6_bind+0x121c/0x1820 net/ipv6/af_inet6.c:399 SYSC_bind+0x3f2/0x4b0 net/socket.c:1474 SyS_bind+0x54/0x80 net/socket.c:1460 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x4416e9 RSP: 002b:00007ffce6d15c88 EFLAGS: 00000217 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 0100000000000000 RCX: 00000000004416e9 RDX: 000000000000001c RSI: 0000000020402000 RDI: 0000000000000004 RBP: 0000000000000000 R08: 00000000e6d15e08 R09: 00000000e6d15e08 R10: 0000000000000004 R11: 0000000000000217 R12: 0000000000009478 R13: 00000000006cd448 R14: 0000000000000000 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_save_stack mm/kmsan/kmsan.c:293 [inline] kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:521 tcp_time_wait+0xf17/0xf50 net/ipv4/tcp_minisocks.c:283 tcp_rcv_state_process+0xebe/0x6490 net/ipv4/tcp_input.c:6003 tcp_v6_do_rcv+0x11dd/0x1d90 net/ipv6/tcp_ipv6.c:1331 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x2d6/0x680 net/core/sock.c:2271 release_sock+0x97/0x2a0 net/core/sock.c:2786 tcp_close+0x277/0x18f0 net/ipv4/tcp.c:2269 inet_release+0x240/0x2a0 net/ipv4/af_inet.c:427 inet6_release+0xaf/0x100 net/ipv6/af_inet6.c:435 sock_release net/socket.c:595 [inline] sock_close+0xe0/0x300 net/socket.c:1149 __fput+0x49e/0xa10 fs/file_table.c:209 ____fput+0x37/0x40 fs/file_table.c:243 task_work_run+0x243/0x2c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x10e1/0x38d0 kernel/exit.c:867 do_group_exit+0x1a0/0x360 kernel/exit.c:970 SYSC_exit_group+0x21/0x30 kernel/exit.c:981 SyS_exit_group+0x25/0x30 kernel/exit.c:979 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_save_stack mm/kmsan/kmsan.c:293 [inline] kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:521 inet_twsk_alloc+0xaef/0xc00 net/ipv4/inet_timewait_sock.c:182 tcp_time_wait+0xd9/0xf50 net/ipv4/tcp_minisocks.c:258 tcp_rcv_state_process+0xebe/0x6490 net/ipv4/tcp_input.c:6003 tcp_v6_do_rcv+0x11dd/0x1d90 net/ipv6/tcp_ipv6.c:1331 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x2d6/0x680 net/core/sock.c:2271 release_sock+0x97/0x2a0 net/core/sock.c:2786 tcp_close+0x277/0x18f0 net/ipv4/tcp.c:2269 inet_release+0x240/0x2a0 net/ipv4/af_inet.c:427 inet6_release+0xaf/0x100 net/ipv6/af_inet6.c:435 sock_release net/socket.c:595 [inline] sock_close+0xe0/0x300 net/socket.c:1149 __fput+0x49e/0xa10 fs/file_table.c:209 ____fput+0x37/0x40 fs/file_table.c:243 task_work_run+0x243/0x2c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x10e1/0x38d0 kernel/exit.c:867 do_group_exit+0x1a0/0x360 kernel/exit.c:970 SYSC_exit_group+0x21/0x30 kernel/exit.c:981 SyS_exit_group+0x25/0x30 kernel/exit.c:979 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmem_cache_alloc+0xaab/0xb90 mm/slub.c:2756 inet_twsk_alloc+0x13b/0xc00 net/ipv4/inet_timewait_sock.c:163 tcp_time_wait+0xd9/0xf50 net/ipv4/tcp_minisocks.c:258 tcp_rcv_state_process+0xebe/0x6490 net/ipv4/tcp_input.c:6003 tcp_v6_do_rcv+0x11dd/0x1d90 net/ipv6/tcp_ipv6.c:1331 sk_backlog_rcv include/net/sock.h:908 [inline] __release_sock+0x2d6/0x680 net/core/sock.c:2271 release_sock+0x97/0x2a0 net/core/sock.c:2786 tcp_close+0x277/0x18f0 net/ipv4/tcp.c:2269 inet_release+0x240/0x2a0 net/ipv4/af_inet.c:427 inet6_release+0xaf/0x100 net/ipv6/af_inet6.c:435 sock_release net/socket.c:595 [inline] sock_close+0xe0/0x300 net/socket.c:1149 __fput+0x49e/0xa10 fs/file_table.c:209 ____fput+0x37/0x40 fs/file_table.c:243 task_work_run+0x243/0x2c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x10e1/0x38d0 kernel/exit.c:867 do_group_exit+0x1a0/0x360 kernel/exit.c:970 SYSC_exit_group+0x21/0x30 kernel/exit.c:981 SyS_exit_group+0x25/0x30 kernel/exit.c:979 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Fixes: da5e36308d9f ("soreuseport: TCP/IPv4 implementation") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip_tunnel: better validate user provided tunnel namesEric Dumazet2018-10-211-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 9cb726a212a82c88c98aa9f0037fd04777cd8fe5 upstream. Use dev_valid_name() to make sure user does not provide illegal device name. syzbot caught the following bug : BUG: KASAN: stack-out-of-bounds in strlcpy include/linux/string.h:300 [inline] BUG: KASAN: stack-out-of-bounds in __ip_tunnel_create+0xca/0x6b0 net/ipv4/ip_tunnel.c:257 Write of size 20 at addr ffff8801ac79f810 by task syzkaller268107/4482 CPU: 0 PID: 4482 Comm: syzkaller268107 Not tainted 4.16.0+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b9/0x29f lib/dump_stack.c:53 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0xac/0x2f5 mm/kasan/report.c:412 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 strlcpy include/linux/string.h:300 [inline] __ip_tunnel_create+0xca/0x6b0 net/ipv4/ip_tunnel.c:257 ip_tunnel_create net/ipv4/ip_tunnel.c:352 [inline] ip_tunnel_ioctl+0x818/0xd40 net/ipv4/ip_tunnel.c:861 ipip_tunnel_ioctl+0x1c5/0x420 net/ipv4/ipip.c:350 dev_ifsioc+0x43e/0xb90 net/core/dev_ioctl.c:334 dev_ioctl+0x69a/0xcc0 net/core/dev_ioctl.c:525 sock_ioctl+0x47e/0x680 net/socket.c:1015 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1cf/0x1650 fs/ioctl.c:684 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 SYSC_ioctl fs/ioctl.c:708 [inline] SyS_ioctl+0x24/0x30 fs/ioctl.c:706 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* Revert "vti4: Don't override MTU passed on link creation via IFLA_MTU"Ben Hutchings2018-09-251-0/+1
| | | | | | | | | | This reverts commit 5a79e43ffa5014c020e0d0f4e383205f87b10111, which was commit 03080e5ec72740c1a62e6730f2a5f3f114f11b19 upstream, as it causes test failures. It should not have been backported to anything older than 4.16. Thanks to Alistair Strachan for debugging this. Cc: Alistair Strachan <astrachan@google.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>