kernel/git/stable/linux.git/net/ipv4, branch linux-5.3.y

gre: refetch erspan header from skb->data after pskb_may_pull()

2019-12-18T15:05:54+00:00

[ Upstream commit 0e4940928c26527ce8f97237fef4c8a91cd34207 ] After pskb_may_pull() we should always refetch the header pointers from the skb->data in case it got reallocated. In gre_parse_header(), the erspan header is still fetched from the 'options' pointer which is fetched before pskb_may_pull(). Found this during code review of a KMSAN bug report. Fixes: cb73ee40b1b3 ("net: ip_gre: use erspan key field for tunnel lookup") Cc: Lorenzo Bianconi Signed-off-by: Cong Wang Acked-by: Lorenzo Bianconi Acked-by: William Tu Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: md5: fix potential overestimation of TCP option space

2019-12-18T15:05:47+00:00

[ Upstream commit 9424e2e7ad93ffffa88f882c9bc5023570904b55 ] Back in 2008, Adam Langley fixed the corner case of packets for flows having all of the following options : MD5 TS SACK Since MD5 needs 20 bytes, and TS needs 12 bytes, no sack block can be cooked from the remaining 8 bytes. tcp_established_options() correctly sets opts->num_sack_blocks to zero, but returns 36 instead of 32. This means TCP cooks packets with 4 extra bytes at the end of options, containing unitialized bytes. Fixes: 33ad798c924b ("tcp: options clean up") Signed-off-by: Eric Dumazet Reported-by: syzbot Acked-by: Neal Cardwell Acked-by: Soheil Hassas Yeganeh Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

inet: protect against too small mtu values.

2019-12-18T15:05:38+00:00

[ Upstream commit 501a90c945103e8627406763dac418f20f3837b2 ] syzbot was once again able to crash a host by setting a very small mtu on loopback device. Let's make inetdev_valid_mtu() available in include/net/ip.h, and use it in ip_setup_cork(), so that we protect both ip_append_page() and __ip_append_data() Also add a READ_ONCE() when the device mtu is read. Pairs this lockless read with one WRITE_ONCE() in __dev_set_mtu(), even if other code paths might write over this field. Add a big comment in include/linux/netdevice.h about dev->mtu needing READ_ONCE()/WRITE_ONCE() annotations. Hopefully we will add the missing ones in followup patches. [1] refcount_t: saturated; leaking memory. WARNING: CPU: 0 PID: 9464 at lib/refcount.c:22 refcount_warn_saturate+0x138/0x1f0 lib/refcount.c:22 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 9464 Comm: syz-executor850 Not tainted 5.4.0-syzkaller #0 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+0x197/0x210 lib/dump_stack.c:118 panic+0x2e3/0x75c kernel/panic.c:221 __warn.cold+0x2f/0x3e kernel/panic.c:582 report_bug+0x289/0x300 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] fixup_bug arch/x86/kernel/traps.c:169 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 RIP: 0010:refcount_warn_saturate+0x138/0x1f0 lib/refcount.c:22 Code: 06 31 ff 89 de e8 c8 f5 e6 fd 84 db 0f 85 6f ff ff ff e8 7b f4 e6 fd 48 c7 c7 e0 71 4f 88 c6 05 56 a6 a4 06 01 e8 c7 a8 b7 fd <0f> 0b e9 50 ff ff ff e8 5c f4 e6 fd 0f b6 1d 3d a6 a4 06 31 ff 89 RSP: 0018:ffff88809689f550 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815e4336 RDI: ffffed1012d13e9c RBP: ffff88809689f560 R08: ffff88809c50a3c0 R09: fffffbfff15d31b1 R10: fffffbfff15d31b0 R11: ffffffff8ae98d87 R12: 0000000000000001 R13: 0000000000040100 R14: ffff888099041104 R15: ffff888218d96e40 refcount_add include/linux/refcount.h:193 [inline] skb_set_owner_w+0x2b6/0x410 net/core/sock.c:1999 sock_wmalloc+0xf1/0x120 net/core/sock.c:2096 ip_append_page+0x7ef/0x1190 net/ipv4/ip_output.c:1383 udp_sendpage+0x1c7/0x480 net/ipv4/udp.c:1276 inet_sendpage+0xdb/0x150 net/ipv4/af_inet.c:821 kernel_sendpage+0x92/0xf0 net/socket.c:3794 sock_sendpage+0x8b/0xc0 net/socket.c:936 pipe_to_sendpage+0x2da/0x3c0 fs/splice.c:458 splice_from_pipe_feed fs/splice.c:512 [inline] __splice_from_pipe+0x3ee/0x7c0 fs/splice.c:636 splice_from_pipe+0x108/0x170 fs/splice.c:671 generic_splice_sendpage+0x3c/0x50 fs/splice.c:842 do_splice_from fs/splice.c:861 [inline] direct_splice_actor+0x123/0x190 fs/splice.c:1035 splice_direct_to_actor+0x3b4/0xa30 fs/splice.c:990 do_splice_direct+0x1da/0x2a0 fs/splice.c:1078 do_sendfile+0x597/0xd00 fs/read_write.c:1464 __do_sys_sendfile64 fs/read_write.c:1525 [inline] __se_sys_sendfile64 fs/read_write.c:1511 [inline] __x64_sys_sendfile64+0x1dd/0x220 fs/read_write.c:1511 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x441409 Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fffb64c4f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441409 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005 RBP: 0000000000073b8a R08: 0000000000000010 R09: 0000000000000010 R10: 0000000000010001 R11: 0000000000000246 R12: 0000000000402180 R13: 0000000000402210 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds.. Fixes: 1470ddf7f8ce ("inet: Remove explicit write references to sk/inet in ip_append_data") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: skmsg: fix TLS 1.3 crash with full sk_msg

2019-12-04T21:34:23+00:00

[ Upstream commit 031097d9e079e40dce401031d1012e83d80eaf01 ] TLS 1.3 started using the entry at the end of the SG array for chaining-in the single byte content type entry. This mostly works: [ E E E E E E . . ] ^ ^ start end E < content type / [ E E E E E E C . ] ^ ^ start end (Where E denotes a populated SG entry; C denotes a chaining entry.) If the array is full, however, the end will point to the start: [ E E E E E E E E ] ^ start end And we end up overwriting the start: E < content type / [ C E E E E E E E ] ^ start end The sg array is supposed to be a circular buffer with start and end markers pointing anywhere. In case where start > end (i.e. the circular buffer has "wrapped") there is an extra entry reserved at the end to chain the two halves together. [ E E E E E E . . l ] (Where l is the reserved entry for "looping" back to front. As suggested by John, let's reserve another entry for chaining SG entries after the main circular buffer. Note that this entry has to be pointed to by the end entry so its position is not fixed. Examples of full messages: [ E E E E E E E E . l ] ^ ^ start end <---------------. [ E E . E E E E E E l ] ^ ^ end start Now the end will always point to an unused entry, so TLS 1.3 can always use it. Fixes: 130b392c6cd6 ("net: tls: Add tls 1.3 support") Signed-off-by: Jakub Kicinski Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net/ipv4: fix sysctl max for fib_multipath_hash_policy

2019-11-29T09:07:39+00:00

[ Upstream commit ca749bbb108c24a876014c804f9777c545be4d59 ] Commit eec4844fae7c ("proc/sysctl: add shared variables for range check") did: - .extra2 = &two, + .extra2 = SYSCTL_ONE, here, which doesn't seem to be intentional, given the changelog. This patch restores it to the previous, as the value of 2 still makes sense (used in fib_multipath_hash()). Fixes: eec4844fae7c ("proc/sysctl: add shared variables for range check") Cc: Matteo Croce Signed-off-by: Marcelo Ricardo Leitner Acked-by: Matteo Croce Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipmr: Fix skb headroom in ipmr_get_route().

2019-11-20T15:48:58+00:00

[ Upstream commit 7901cd97963d6cbde88fa25a4a446db3554c16c6 ] In route.c, inet_rtm_getroute_build_skb() creates an skb with no headroom. This skb is then used by inet_rtm_getroute() which may pass it to rt_fill_info() and, from there, to ipmr_get_route(). The later might try to reuse this skb by cloning it and prepending an IPv4 header. But since the original skb has no headroom, skb_push() triggers skb_under_panic(): skbuff: skb_under_panic: text:00000000ca46ad8a len:80 put:20 head:00000000cd28494e data:000000009366fd6b tail:0x3c end:0xec0 dev:veth0 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:108! invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 6 PID: 587 Comm: ip Not tainted 5.4.0-rc6+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 RIP: 0010:skb_panic+0xbf/0xd0 Code: 41 a2 ff 8b 4b 70 4c 8b 4d d0 48 c7 c7 20 76 f5 8b 44 8b 45 bc 48 8b 55 c0 48 8b 75 c8 41 54 41 57 41 56 41 55 e8 75 dc 7a ff <0f> 0b 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 RSP: 0018:ffff888059ddf0b0 EFLAGS: 00010286 RAX: 0000000000000086 RBX: ffff888060a315c0 RCX: ffffffff8abe4822 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88806c9a79cc RBP: ffff888059ddf118 R08: ffffed100d9361b1 R09: ffffed100d9361b0 R10: ffff88805c68aee3 R11: ffffed100d9361b1 R12: ffff88805d218000 R13: ffff88805c689fec R14: 000000000000003c R15: 0000000000000ec0 FS: 00007f6af184b700(0000) GS:ffff88806c980000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc8204a000 CR3: 0000000057b40006 CR4: 0000000000360ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_push+0x7e/0x80 ipmr_get_route+0x459/0x6fa rt_fill_info+0x692/0x9f0 inet_rtm_getroute+0xd26/0xf20 rtnetlink_rcv_msg+0x45d/0x630 netlink_rcv_skb+0x1a5/0x220 rtnetlink_rcv+0x15/0x20 netlink_unicast+0x305/0x3a0 netlink_sendmsg+0x575/0x730 sock_sendmsg+0xb5/0xc0 ___sys_sendmsg+0x497/0x4f0 __sys_sendmsg+0xcb/0x150 __x64_sys_sendmsg+0x48/0x50 do_syscall_64+0xd2/0xac0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Actually the original skb used to have enough headroom, but the reserve_skb() call was lost with the introduction of inet_rtm_getroute_build_skb() by commit 404eb77ea766 ("ipv4: support sport, dport and ip_proto in RTM_GETROUTE"). We could reserve some headroom again in inet_rtm_getroute_build_skb(), but this function shouldn't be responsible for handling the special case of ipmr_get_route(). Let's handle that directly in ipmr_get_route() by calling skb_realloc_headroom() instead of skb_clone(). Fixes: 404eb77ea766 ("ipv4: support sport, dport and ip_proto in RTM_GETROUTE") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv4: Fix table id reference in fib_sync_down_addr

2019-11-12T18:26:35+00:00

[ Upstream commit e0a312629fefa943534fc46f7bfbe6de3fdaf463 ] Hendrik reported routes in the main table using source address are not removed when the address is removed. The problem is that fib_sync_down_addr does not account for devices in the default VRF which are associated with the main table. Fix by updating the table id reference. Fixes: 5a56a0b3a45d ("net: Don't delete routes in different VRFs") Reported-by: Hendrik Donner Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ensure correct skb->tstamp in various fragmenters

2019-11-10T10:34:52+00:00

[ Upstream commit 9669fffc1415bb0c30e5d2ec98a8e1c3a418cb9c ] Thomas found that some forwarded packets would be stuck in FQ packet scheduler because their skb->tstamp contained timestamps far in the future. We thought we addressed this point in commit 8203e2d844d3 ("net: clear skb->tstamp in forwarding paths") but there is still an issue when/if a packet needs to be fragmented. In order to meet EDT requirements, we have to make sure all fragments get the original skb->tstamp. Note that this original skb->tstamp should be zero in forwarding path, but might have a non zero value in output path if user decided so. Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC") Signed-off-by: Eric Dumazet Reported-by: Thomas Bartschies Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv4: fix IPSKB_FRAG_PMTU handling with fragmentation

2019-11-10T10:34:51+00:00

[ Upstream commit e7a409c3f46cb0dbc7bfd4f6f9421d53e92614a5 ] This patch removes the iph field from the state structure, which is not properly initialized. Instead, add a new field to make the "do we want to set DF" be the state bit and move the code to set the DF flag from ip_frag_next(). Joint work with Pablo and Linus. Fixes: 19c3401a917b ("net: ipv4: place control buffer handling away from fragmentation iterators") Reported-by: Patrick Schönthaler Signed-off-by: Eric Dumazet Signed-off-by: Pablo Neira Ayuso Signed-off-by: Linus Torvalds Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv4: fix route update on metric change.

2019-11-10T10:34:45+00:00

[ Upstream commit 0b834ba00ab5337e938c727e216e1f5249794717 ] Since commit af4d768ad28c ("net/ipv4: Add support for specifying metric of connected routes"), when updating an IP address with a different metric, the associated connected route is updated, too. Still, the mentioned commit doesn't handle properly some corner cases: $ ip addr add dev eth0 192.168.1.0/24 $ ip addr add dev eth0 192.168.2.1/32 peer 192.168.2.2 $ ip addr add dev eth0 192.168.3.1/24 $ ip addr change dev eth0 192.168.1.0/24 metric 10 $ ip addr change dev eth0 192.168.2.1/32 peer 192.168.2.2 metric 10 $ ip addr change dev eth0 192.168.3.1/24 metric 10 $ ip -4 route 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.0 192.168.2.2 dev eth0 proto kernel scope link src 192.168.2.1 192.168.3.0/24 dev eth0 proto kernel scope link src 192.168.2.1 metric 10 Only the last route is correctly updated. The problem is the current test in fib_modify_prefix_metric(): if (!(dev->flags & IFF_UP) || ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) || ipv4_is_zeronet(prefix) || prefix == ifa->ifa_local || ifa->ifa_prefixlen == 32) Which should be the logical 'not' of the pre-existing test in fib_add_ifaddr(): if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) && (prefix != addr || ifa->ifa_prefixlen < 32)) To properly negate the original expression, we need to change the last logical 'or' to a logical 'and'. Fixes: af4d768ad28c ("net/ipv4: Add support for specifying metric of connected routes") Reported-and-suggested-by: Beniamino Galvani Signed-off-by: Paolo Abeni Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman