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2018-11-19net: skb_scrub_packet(): Scrub offload_fwd_markPetr Machata1-0/+5
When a packet is trapped and the corresponding SKB marked as already-forwarded, it retains this marking even after it is forwarded across veth links into another bridge. There, since it ingresses the bridge over veth, which doesn't have offload_fwd_mark, it triggers a warning in nbp_switchdev_frame_mark(). Then nbp_switchdev_allowed_egress() decides not to allow egress from this bridge through another veth, because the SKB is already marked, and the mark (of 0) of course matches. Thus the packet is incorrectly blocked. Solve by resetting offload_fwd_mark() in skb_scrub_packet(). That function is called from tunnels and also from veth, and thus catches the cases where traffic is forwarded between bridges and transformed in a way that invalidates the marking. Signed-off-by: Petr Machata <petrm@mellanox.com> Suggested-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-16net: remove unused skb_send_sock()Cong Wang1-13/+0
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-15net: remove BUG_ON from __pskb_pull_tailLi RongQing1-2/+0
if list is NULL pointer, and the following access of list will trigger panic, which is same as BUG_ON Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-15net: dump more useful information in netdev_rx_csum_fault()Cong Wang1-2/+2
Currently netdev_rx_csum_fault() only shows a device name, we need more information about the skb for debugging csum failures. Sample output: ens3: hw csum failure dev features: 0x0000000000014b89 skb len=84 data_len=0 pkt_type=0 gso_size=0 gso_type=0 nr_frags=0 ip_summed=0 csum=0 csum_complete_sw=0 csum_valid=0 csum_level=0 Note, I use pr_err() just to be consistent with the existing one. Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08net/core: use __vlan_hwaccel helpersMichał Mirosław1-1/+1
This removes assumptions about VLAN_TAG_PRESENT bit. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08net: move __skb_checksum_complete*() to skbuff.cCong Wang1-0/+43
__skb_checksum_complete_head() and __skb_checksum_complete() are both declared in skbuff.h, they fit better in skbuff.c than datagram.c. Cc: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-02net: document skb parameter in function 'skb_gso_size_check'Mathieu Malaterre1-0/+2
Remove kernel-doc warning: net/core/skbuff.c:4953: warning: Function parameter or member 'skb' not described in 'skb_gso_size_check' Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+3
David Ahern's dump indexing bug fix in 'net' overlapped the change of the function signature of inet6_fill_ifaddr() in 'net-next'. Trivially resolved. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-20net: fix pskb_trim_rcsum_slow() with odd trim offsetDimitris Michailidis1-2/+3
We've been getting checksum errors involving small UDP packets, usually 59B packets with 1 extra non-zero padding byte. netdev_rx_csum_fault() has been complaining that HW is providing bad checksums. Turns out the problem is in pskb_trim_rcsum_slow(), introduced in commit 88078d98d1bb ("net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends"). The source of the problem is that when the bytes we are trimming start at an odd address, as in the case of the 1 padding byte above, skb_checksum() returns a byte-swapped value. We cannot just combine this with skb->csum using csum_sub(). We need to use csum_block_sub() here that takes into account the parity of the start address and handles the swapping. Matches existing code in __skb_postpull_rcsum() and esp_remove_trailer(). Fixes: 88078d98d1bb ("net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends") Signed-off-by: Dimitris Michailidis <dmichail@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-5/+7
Conflicts were easy to resolve using immediate context mostly, except the cls_u32.c one where I simply too the entire HEAD chunk. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-10net: make skb_partial_csum_set() more robust against overflowsEric Dumazet1-5/+7
syzbot managed to crash in skb_checksum_help() [1] : BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); Root cause is the following check in skb_partial_csum_set() if (unlikely(start > skb_headlen(skb)) || unlikely((int)start + off > skb_headlen(skb) - 2)) return false; If skb_headlen(skb) is 1, then (skb_headlen(skb) - 2) becomes 0xffffffff and the check fails to detect that ((int)start + off) is off the limit, since the compare is unsigned. When we fix that, then the first condition (start > skb_headlen(skb)) becomes obsolete. Then we should also check that (skb_headroom(skb) + start) wont overflow 16bit field. [1] kernel BUG at net/core/dev.c:2880! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 7330 Comm: syz-executor4 Not tainted 4.19.0-rc6+ #253 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:skb_checksum_help+0x9e3/0xbb0 net/core/dev.c:2880 Code: 85 00 ff ff ff 48 c1 e8 03 42 80 3c 28 00 0f 84 09 fb ff ff 48 8b bd 00 ff ff ff e8 97 a8 b9 fb e9 f8 fa ff ff e8 2d 09 76 fb <0f> 0b 48 8b bd 28 ff ff ff e8 1f a8 b9 fb e9 b1 f6 ff ff 48 89 cf RSP: 0018:ffff8801d83a6f60 EFLAGS: 00010293 RAX: ffff8801b9834380 RBX: ffff8801b9f8d8c0 RCX: ffffffff8608c6d7 RDX: 0000000000000000 RSI: ffffffff8608cc63 RDI: 0000000000000006 RBP: ffff8801d83a7068 R08: ffff8801b9834380 R09: 0000000000000000 R10: ffff8801d83a76d8 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000010001 R14: 000000000000ffff R15: 00000000000000a8 FS: 00007f1a66db5700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7d77f091b0 CR3: 00000001ba252000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_csum_hwoffload_help+0x8f/0xe0 net/core/dev.c:3269 validate_xmit_skb+0xa2a/0xf30 net/core/dev.c:3312 __dev_queue_xmit+0xc2f/0x3950 net/core/dev.c:3797 dev_queue_xmit+0x17/0x20 net/core/dev.c:3838 packet_snd net/packet/af_packet.c:2928 [inline] packet_sendmsg+0x422d/0x64c0 net/packet/af_packet.c:2953 Fixes: 5ff8dda3035d ("net: Ensure partial checksum offset is inside the skb head") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: drop unused skb_append_datato_frags()Paolo Abeni1-58/+0
This helper is unused since commit 988cf74deb45 ("inet: Stop generating UFO packets.") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-07tcp: really ignore MSG_ZEROCOPY if no SO_ZEROCOPYVincent Whitchurch1-3/+0
According to the documentation in msg_zerocopy.rst, the SO_ZEROCOPY flag was introduced because send(2) ignores unknown message flags and any legacy application which was accidentally passing the equivalent of MSG_ZEROCOPY earlier should not see any new behaviour. Before commit f214f915e7db ("tcp: enable MSG_ZEROCOPY"), a send(2) call which passed the equivalent of MSG_ZEROCOPY without setting SO_ZEROCOPY would succeed. However, after that commit, it fails with -ENOBUFS. So it appears that the SO_ZEROCOPY flag fails to fulfill its intended purpose. Fix it. Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-10net: Export skb_headers_offset_updateToshiaki Makita1-1/+2
This is needed for veth XDP which does skb_copy_expand()-like operation. v2: - Drop skb_copy_header part because it has already been exported now. Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-05net: modify skb_rbtree_purge to return the truesize of all purged skbs.Peter Oskolkov1-1/+5
Tested: see the next patch is the series. Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Peter Oskolkov <posk@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-02net: Fix coding style in skb_push()Ganesh Goudar1-1/+1
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-5/+5
2018-07-21net: skb_segment() should not return NULLEric Dumazet1-5/+5
syzbot caught a NULL deref [1], caused by skb_segment() skb_segment() has many "goto err;" that assume the @err variable contains -ENOMEM. A successful call to __skb_linearize() should not clear @err, otherwise a subsequent memory allocation error could return NULL. While we are at it, we might use -EINVAL instead of -ENOMEM when MAX_SKB_FRAGS limit is reached. [1] kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN CPU: 0 PID: 13285 Comm: syz-executor3 Not tainted 4.18.0-rc4+ #146 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:tcp_gso_segment+0x3dc/0x1780 net/ipv4/tcp_offload.c:106 Code: f0 ff ff 0f 87 1c fd ff ff e8 00 88 0b fb 48 8b 75 d0 48 b9 00 00 00 00 00 fc ff df 48 8d be 90 00 00 00 48 89 f8 48 c1 e8 03 <0f> b6 14 08 48 8d 86 94 00 00 00 48 89 c6 83 e0 07 48 c1 ee 03 0f RSP: 0018:ffff88019b7fd060 EFLAGS: 00010206 RAX: 0000000000000012 RBX: 0000000000000020 RCX: dffffc0000000000 RDX: 0000000000040000 RSI: 0000000000000000 RDI: 0000000000000090 RBP: ffff88019b7fd0f0 R08: ffff88019510e0c0 R09: ffffed003b5c46d6 R10: ffffed003b5c46d6 R11: ffff8801dae236b3 R12: 0000000000000001 R13: ffff8801d6c581f4 R14: 0000000000000000 R15: ffff8801d6c58128 FS: 00007fcae64d6700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004e8664 CR3: 00000001b669b000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tcp4_gso_segment+0x1c3/0x440 net/ipv4/tcp_offload.c:54 inet_gso_segment+0x64e/0x12d0 net/ipv4/af_inet.c:1342 inet_gso_segment+0x64e/0x12d0 net/ipv4/af_inet.c:1342 skb_mac_gso_segment+0x3b5/0x740 net/core/dev.c:2792 __skb_gso_segment+0x3c3/0x880 net/core/dev.c:2865 skb_gso_segment include/linux/netdevice.h:4099 [inline] validate_xmit_skb+0x640/0xf30 net/core/dev.c:3104 __dev_queue_xmit+0xc14/0x3910 net/core/dev.c:3561 dev_queue_xmit+0x17/0x20 net/core/dev.c:3602 neigh_hh_output include/net/neighbour.h:473 [inline] neigh_output include/net/neighbour.h:481 [inline] ip_finish_output2+0x1063/0x1860 net/ipv4/ip_output.c:229 ip_finish_output+0x841/0xfa0 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:276 [inline] ip_output+0x223/0x880 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124 iptunnel_xmit+0x567/0x850 net/ipv4/ip_tunnel_core.c:91 ip_tunnel_xmit+0x1598/0x3af1 net/ipv4/ip_tunnel.c:778 ipip_tunnel_xmit+0x264/0x2c0 net/ipv4/ipip.c:308 __netdev_start_xmit include/linux/netdevice.h:4148 [inline] netdev_start_xmit include/linux/netdevice.h:4157 [inline] xmit_one net/core/dev.c:3034 [inline] dev_hard_start_xmit+0x26c/0xc30 net/core/dev.c:3050 __dev_queue_xmit+0x29ef/0x3910 net/core/dev.c:3569 dev_queue_xmit+0x17/0x20 net/core/dev.c:3602 neigh_direct_output+0x15/0x20 net/core/neighbour.c:1403 neigh_output include/net/neighbour.h:483 [inline] ip_finish_output2+0xa67/0x1860 net/ipv4/ip_output.c:229 ip_finish_output+0x841/0xfa0 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:276 [inline] ip_output+0x223/0x880 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124 ip_queue_xmit+0x9df/0x1f80 net/ipv4/ip_output.c:504 tcp_transmit_skb+0x1bf9/0x3f10 net/ipv4/tcp_output.c:1168 tcp_write_xmit+0x1641/0x5c20 net/ipv4/tcp_output.c:2363 __tcp_push_pending_frames+0xb2/0x290 net/ipv4/tcp_output.c:2536 tcp_push+0x638/0x8c0 net/ipv4/tcp.c:735 tcp_sendmsg_locked+0x2ec5/0x3f00 net/ipv4/tcp.c:1410 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1447 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:641 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:651 __sys_sendto+0x3d7/0x670 net/socket.c:1797 __do_sys_sendto net/socket.c:1809 [inline] __se_sys_sendto net/socket.c:1805 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1805 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455ab9 Code: 1d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fcae64d5c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fcae64d66d4 RCX: 0000000000455ab9 RDX: 0000000000000001 RSI: 0000000020000200 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000014 R13: 00000000004c1145 R14: 00000000004d1818 R15: 0000000000000006 Modules linked in: Dumping ftrace buffer: (ftrace buffer empty) Fixes: ddff00d42043 ("net: Move skb_has_shared_frag check out of GRE code and into segmentation") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-20Merge ra.kernel.org:/pub/scm/linux/kernel/git/torvalds/linuxDavid S. Miller1-0/+1
All conflicts were trivial overlapping changes, so reasonably easy to resolve. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-18net: Move skb decrypted field, avoid explicity copyStefano Brivio1-6/+0
Commit 784abe24c903 ("net: Add decrypted field to skb") introduced a 'decrypted' field that is explicitly copied on skb copy and clone. Move it between headers_start[0] and headers_end[0], so that we don't need to copy it explicitly as it's copied by the memcpy() in __copy_skb_header(). While at it, drop the assignment in __skb_clone(), it was already redundant. This doesn't change the size of sk_buff or cacheline boundaries. The 15-bits hole before tc_index becomes a 14-bits hole, and will be again a 15-bits hole when this change is merged with commit 8b7008620b84 ("net: Don't copy pfmemalloc flag in __copy_skb_header()"). v2: as reported by kbuild test robot (oops, I forgot to build with CONFIG_TLS_DEVICE it seems), we can't use CHECK_SKB_FIELD() on a bit-field member. Just drop the check for the moment being, perhaps we could think of some magic to also check bit-field members one day. Fixes: 784abe24c903 ("net: Add decrypted field to skb") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-16net: Add decrypted field to skbBoris Pismenny1-0/+6
The decrypted bit is propogated to cloned/copied skbs. This will be used later by the inline crypto receive side offload of tls. Signed-off-by: Boris Pismenny <borisp@mellanox.com> Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-13skbuff: Unconditionally copy pfmemalloc in __skb_clone()Stefano Brivio1-2/+1
Commit 8b7008620b84 ("net: Don't copy pfmemalloc flag in __copy_skb_header()") introduced a different handling for the pfmemalloc flag in copy and clone paths. In __skb_clone(), now, the flag is set only if it was set in the original skb, but not cleared if it wasn't. This is wrong and might lead to socket buffers being flagged with pfmemalloc even if the skb data wasn't allocated from pfmemalloc reserves. Copy the flag instead of ORing it. Reported-by: Sabrina Dubroca <sd@queasysnail.net> Fixes: 8b7008620b84 ("net: Don't copy pfmemalloc flag in __copy_skb_header()") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Tested-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12net: Don't copy pfmemalloc flag in __copy_skb_header()Stefano Brivio1-0/+2
The pfmemalloc flag indicates that the skb was allocated from the PFMEMALLOC reserves, and the flag is currently copied on skb copy and clone. However, an skb copied from an skb flagged with pfmemalloc wasn't necessarily allocated from PFMEMALLOC reserves, and on the other hand an skb allocated that way might be copied from an skb that wasn't. So we should not copy the flag on skb copy, and rather decide whether to allow an skb to be associated with sockets unrelated to page reclaim depending only on how it was allocated. Move the pfmemalloc flag before headers_start[0] using an existing 1-bit hole, so that __copy_skb_header() doesn't copy it. When cloning, we'll now take care of this flag explicitly, contravening to the warning comment of __skb_clone(). While at it, restore the newline usage introduced by commit b19372273164 ("net: reorganize sk_buff for faster __copy_skb_header()") to visually separate bytes used in bitfields after headers_start[0], that was gone after commit a9e419dc7be6 ("netfilter: merge ctinfo into nfct pointer storage area"), and describe the pfmemalloc flag in the kernel-doc structure comment. This doesn't change the size of sk_buff or cacheline boundaries, but consolidates the 15 bits hole before tc_index into a 2 bytes hole before csum, that could now be filled more easily. Reported-by: Patrick Talbert <ptalbert@redhat.com> Fixes: c93bdd0e03e8 ("netvm: allow skb allocation to use PFMEMALLOC reserves") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-04net: Clear skb->tstamp only on the forwarding pathJesus Sanchez-Palencia1-1/+1
This is done in preparation for the upcoming time based transmission patchset. Now that skb->tstamp will be used to hold packet's txtime, we must ensure that it is being cleared when traversing namespaces. Also, doing that from skb_scrub_packet() before the early return would break our feature when tunnels are used. Signed-off-by: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-03Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+1
Simple overlapping changes in stmmac driver. Adjust skb_gro_flush_final_remcsum function signature to make GRO list changes in net-next, as per Stephen Rothwell's example merge resolution. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-30net: cleanup gfp mask in alloc_skb_with_fragsMichal Hocko1-2/+1
alloc_skb_with_frags uses __GFP_NORETRY for non-sleeping allocations which is just a noop and a little bit confusing. __GFP_NORETRY was added by ed98df3361f0 ("net: use __GFP_NORETRY for high order allocations") to prevent from the OOM killer. Yet this was not enough because fb05e7a89f50 ("net: don't wait for order-3 page allocation") didn't want an excessive reclaim for non-costly orders so it made it completely NOWAIT while it preserved __GFP_NORETRY in place which is now redundant. Drop the pointless __GFP_NORETRY because this function is used as copy&paste source for other places. Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-28skbuff: preserve sock reference when scrubbing the skb.Flavio Leitner1-1/+0
The sock reference is lost when scrubbing the packet and that breaks TSQ (TCP Small Queues) and XPS (Transmit Packet Steering) causing performance impacts of about 50% in a single TCP stream when crossing network namespaces. XPS breaks because the queue mapping stored in the socket is not available, so another random queue might be selected when the stack needs to transmit something like a TCP ACK, or TCP Retransmissions. That causes packet re-ordering and/or performance issues. TSQ breaks because it orphans the packet while it is still in the host, so packets are queued contributing to the buffer bloat problem. Preserving the sock reference fixes both issues. The socket is orphaned anyways in the receiving path before any relevant action and on TX side the netfilter checks if the reference is local before use it. Signed-off-by: Flavio Leitner <fbl@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-26net: Convert GRO SKB handling to list_head.David Miller1-2/+2
Manage pending per-NAPI GRO packets via list_head. Return an SKB pointer from the GRO receive handlers. When GRO receive handlers return non-NULL, it means that this SKB needs to be completed at this time and removed from the NAPI queue. Several operations are greatly simplified by this transformation, especially timing out the oldest SKB in the list when gro_count exceeds MAX_GRO_SKBS, and napi_gro_flush() which walks the queue in reverse order. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-01net: Rename and export copy_skb_headerIlya Lesokhin1-4/+5
copy_skb_header is renamed to skb_copy_header and exported. Exposing this function give more flexibility in copying SKBs. skb_copy and skb_copy_expand do not give enough control over which parts are copied. Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com> Signed-off-by: Boris Pismenny <borisp@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26udp: add udp gsoWillem de Bruijn1-0/+2
Implement generic segmentation offload support for udp datagrams. A follow-up patch adds support to the protocol stack to generate such packets. UDP GSO is not UFO. UFO fragments a single large datagram. GSO splits a large payload into a number of discrete UDP datagrams. The implementation adds a GSO type SKB_UDP_GSO_L4 to differentiate it from UFO (SKB_UDP_GSO). IPPROTO_UDPLITE is excluded, as that protocol has no gso handler registered. [ Export __udp_gso_segment for ipv6. -DaveM ] Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-19net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friendsEric Dumazet1-0/+14
After working on IP defragmentation lately, I found that some large packets defeat CHECKSUM_COMPLETE optimization because of NIC adding zero paddings on the last (small) fragment. While removing the padding with pskb_trim_rcsum(), we set skb->ip_summed to CHECKSUM_NONE, forcing a full csum validation, even if all prior fragments had CHECKSUM_COMPLETE set. We can instead compute the checksum of the part we are trimming, usually smaller than the part we keep. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-07net: initialize skb->peeked when cloningEric Dumazet1-0/+1
syzbot reported __skb_try_recv_from_queue() was using skb->peeked while it was potentially unitialized. We need to clear it in __skb_clone() Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+4
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c, we had some overlapping changes: 1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE --> MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE 2) In 'net-next' params->log_rq_size is renamed to be params->log_rq_mtu_frames. 3) In 'net-next' params->hard_mtu is added. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-30net: Fix untag for vlan packets without ethernet headerToshiaki Makita1-2/+4
In some situation vlan packets do not have ethernet headers. One example is packets from tun devices. Users can specify vlan protocol in tun_pi field instead of IP protocol, and skb_vlan_untag() attempts to untag such packets. skb_vlan_untag() (more precisely, skb_reorder_vlan_header() called by it) however did not expect packets without ethernet headers, so in such a case size argument for memmove() underflowed and triggered crash. ==== BUG: unable to handle kernel paging request at ffff8801cccb8000 IP: __memmove+0x24/0x1a0 arch/x86/lib/memmove_64.S:43 PGD 9cee067 P4D 9cee067 PUD 1d9401063 PMD 1cccb7063 PTE 2810100028101 Oops: 000b [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 17663 Comm: syz-executor2 Not tainted 4.16.0-rc7+ #368 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__memmove+0x24/0x1a0 arch/x86/lib/memmove_64.S:43 RSP: 0018:ffff8801cc046e28 EFLAGS: 00010287 RAX: ffff8801ccc244c4 RBX: fffffffffffffffe RCX: fffffffffff6c4c2 RDX: fffffffffffffffe RSI: ffff8801cccb7ffc RDI: ffff8801cccb8000 RBP: ffff8801cc046e48 R08: ffff8801ccc244be R09: ffffed0039984899 R10: 0000000000000001 R11: ffffed0039984898 R12: ffff8801ccc244c4 R13: ffff8801ccc244c0 R14: ffff8801d96b7c06 R15: ffff8801d96b7b40 FS: 00007febd562d700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff8801cccb8000 CR3: 00000001ccb2f006 CR4: 00000000001606e0 DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: memmove include/linux/string.h:360 [inline] skb_reorder_vlan_header net/core/skbuff.c:5031 [inline] skb_vlan_untag+0x470/0xc40 net/core/skbuff.c:5061 __netif_receive_skb_core+0x119c/0x3460 net/core/dev.c:4460 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4627 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4701 netif_receive_skb+0xae/0x390 net/core/dev.c:4725 tun_rx_batched.isra.50+0x5ee/0x870 drivers/net/tun.c:1555 tun_get_user+0x299e/0x3c20 drivers/net/tun.c:1962 tun_chr_write_iter+0xb9/0x160 drivers/net/tun.c:1990 call_write_iter include/linux/fs.h:1782 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x684/0x970 fs/read_write.c:482 vfs_write+0x189/0x510 fs/read_write.c:544 SYSC_write fs/read_write.c:589 [inline] SyS_write+0xef/0x220 fs/read_write.c:581 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x454879 RSP: 002b:00007febd562cc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007febd562d6d4 RCX: 0000000000454879 RDX: 0000000000000157 RSI: 0000000020000180 RDI: 0000000000000014 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000006b0 R14: 00000000006fc120 R15: 0000000000000000 Code: 90 90 90 90 90 90 90 48 89 f8 48 83 fa 20 0f 82 03 01 00 00 48 39 fe 7d 0f 49 89 f0 49 01 d0 49 39 f8 0f 8f 9f 00 00 00 48 89 d1 <f3> a4 c3 48 81 fa a8 02 00 00 72 05 40 38 fe 74 3b 48 83 ea 20 RIP: __memmove+0x24/0x1a0 arch/x86/lib/memmove_64.S:43 RSP: ffff8801cc046e28 CR2: ffff8801cccb8000 ==== We don't need to copy headers for packets which do not have preceding headers of vlan headers, so skip memmove() in that case. Fixes: 4bbb3e0e8239 ("net: Fix vlan untag for bridge and vlan_dev with reorder_hdr off") Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-25net: permit skb_segment on head_frag frag_list skbYonghong Song1-5/+22
One of our in-house projects, bpf-based NAT, hits a kernel BUG_ON at function skb_segment(), line 3667. The bpf program attaches to clsact ingress, calls bpf_skb_change_proto to change protocol from ipv4 to ipv6 or from ipv6 to ipv4, and then calls bpf_redirect to send the changed packet out. 3472 struct sk_buff *skb_segment(struct sk_buff *head_skb, 3473 netdev_features_t features) 3474 { 3475 struct sk_buff *segs = NULL; 3476 struct sk_buff *tail = NULL; ... 3665 while (pos < offset + len) { 3666 if (i >= nfrags) { 3667 BUG_ON(skb_headlen(list_skb)); 3668 3669 i = 0; 3670 nfrags = skb_shinfo(list_skb)->nr_frags; 3671 frag = skb_shinfo(list_skb)->frags; 3672 frag_skb = list_skb; ... call stack: ... #1 [ffff883ffef03558] __crash_kexec at ffffffff8110c525 #2 [ffff883ffef03620] crash_kexec at ffffffff8110d5cc #3 [ffff883ffef03640] oops_end at ffffffff8101d7e7 #4 [ffff883ffef03668] die at ffffffff8101deb2 #5 [ffff883ffef03698] do_trap at ffffffff8101a700 #6 [ffff883ffef036e8] do_error_trap at ffffffff8101abfe #7 [ffff883ffef037a0] do_invalid_op at ffffffff8101acd0 #8 [ffff883ffef037b0] invalid_op at ffffffff81a00bab [exception RIP: skb_segment+3044] RIP: ffffffff817e4dd4 RSP: ffff883ffef03860 RFLAGS: 00010216 RAX: 0000000000002bf6 RBX: ffff883feb7aaa00 RCX: 0000000000000011 RDX: ffff883fb87910c0 RSI: 0000000000000011 RDI: ffff883feb7ab500 RBP: ffff883ffef03928 R8: 0000000000002ce2 R9: 00000000000027da R10: 000001ea00000000 R11: 0000000000002d82 R12: ffff883f90a1ee80 R13: ffff883fb8791120 R14: ffff883feb7abc00 R15: 0000000000002ce2 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #9 [ffff883ffef03930] tcp_gso_segment at ffffffff818713e7 Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+7
Fun set of conflict resolutions here... For the mac80211 stuff, these were fortunately just parallel adds. Trivially resolved. In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the function phy_disable_interrupts() earlier in the file, whilst in 'net-next' the phy_error() call from this function was removed. In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the 'rt_table_id' member of rtable collided with a bug fix in 'net' that added a new struct member "rt_mtu_locked" which needs to be copied over here. The mlxsw driver conflict consisted of net-next separating the span code and definitions into separate files, whilst a 'net' bug fix made some changes to that moved code. The mlx5 infiniband conflict resolution was quite non-trivial, the RDMA tree's merge commit was used as a guide here, and here are their notes: ==================== Due to bug fixes found by the syzkaller bot and taken into the for-rc branch after development for the 4.17 merge window had already started being taken into the for-next branch, there were fairly non-trivial merge issues that would need to be resolved between the for-rc branch and the for-next branch. This merge resolves those conflicts and provides a unified base upon which ongoing development for 4.17 can be based. Conflicts: drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f9524 (IB/mlx5: Fix cleanup order on unload) added to for-rc and commit b5ca15ad7e61 (IB/mlx5: Add proper representors support) add as part of the devel cycle both needed to modify the init/de-init functions used by mlx5. To support the new representors, the new functions added by the cleanup patch needed to be made non-static, and the init/de-init list added by the representors patch needed to be modified to match the init/de-init list changes made by the cleanup patch. Updates: drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function prototypes added by representors patch to reflect new function names as changed by cleanup patch drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init stage list to match new order from cleanup patch ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-16skbuff: Fix not waking applications when errors are enqueuedVinicius Costa Gomes1-1/+1
When errors are enqueued to the error queue via sock_queue_err_skb() function, it is possible that the waiting application is not notified. Calling 'sk->sk_data_ready()' would not notify applications that selected only POLLERR events in poll() (for example). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Randy E. Witt <randy.e.witt@intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-16net: Fix vlan untag for bridge and vlan_dev with reorder_hdr offToshiaki Makita1-2/+5
When we have a bridge with vlan_filtering on and a vlan device on top of it, packets would be corrupted in skb_vlan_untag() called from br_dev_xmit(). The problem sits in skb_reorder_vlan_header() used in skb_vlan_untag(), which makes use of skb->mac_len. In this function mac_len is meant for handling rx path with vlan devices with reorder_header disabled, but in tx path mac_len is typically 0 and cannot be used, which is the problem in this case. The current code even does not properly handle rx path (skb_vlan_untag() called from __netif_receive_skb_core()) with reorder_header off actually. In rx path single tag case, it works as follows: - Before skb_reorder_vlan_header() mac_header data v v +-------------------+-------------+------+---- | ETH | VLAN | ETH | | ADDRS | TPID | TCI | TYPE | +-------------------+-------------+------+---- <-------- mac_len ---------> <-------------> to be removed - After skb_reorder_vlan_header() mac_header data v v +-------------------+------+---- | ETH | ETH | | ADDRS | TYPE | +-------------------+------+---- <-------- mac_len ---------> This is ok, but in rx double tag case, it corrupts packets: - Before skb_reorder_vlan_header() mac_header data v v +-------------------+-------------+-------------+------+---- | ETH | VLAN | VLAN | ETH | | ADDRS | TPID | TCI | TPID | TCI | TYPE | +-------------------+-------------+-------------+------+---- <--------------- mac_len ----------------> <-------------> should be removed <---------------------------> actually will be removed - After skb_reorder_vlan_header() mac_header data v v +-------------------+------+---- | ETH | ETH | | ADDRS | TYPE | +-------------------+------+---- <--------------- mac_len ----------------> So, two of vlan tags are both removed while only inner one should be removed and mac_header (and mac_len) is broken. skb_vlan_untag() is meant for removing the vlan header at (skb->data - 2), so use skb->data and skb->mac_header to calculate the right offset. Reported-by: Brandon Carpenter <brandon.carpenter@cypherpath.com> Fixes: a6e18ff11170 ("vlan: Fix untag operations of stacked vlans with REORDER_HEADER off") Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09net: use skb_is_gso_sctp() instead of open-codingDaniel Axtens1-1/+1
As well as the basic conversion, I noticed that a lot of the SCTP code checks gso_type without first checking skb_is_gso() so I have added that where appropriate. Also, document the helper. Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-7/+41
All of the conflicts were cases of overlapping changes. In net/core/devlink.c, we have to make care that the resouce size_params have become a struct member rather than a pointer to such an object. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04net: make skb_gso_*_seglen functions privateDaniel Axtens1-2/+35
They're very hard to use properly as they do not consider the GSO_BY_FRAGS case. Code should use skb_gso_validate_network_len and skb_gso_validate_mac_len as they do consider this case. Make the seglen functions static, which stops people using them outside of skbuff.c Signed-off-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04net: rename skb_gso_validate_mtu -> skb_gso_validate_network_lenDaniel Axtens1-5/+6
If you take a GSO skb, and split it into packets, will the network length (L3 headers + L4 headers + payload) of those packets be small enough to fit within a given MTU? skb_gso_validate_mtu gives you the answer to that question. However, we recently added to add a way to validate the MAC length of a split GSO skb (L2+L3+L4+payload), and the names get confusing, so rename skb_gso_validate_mtu to skb_gso_validate_network_len Signed-off-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-26net: make kmem caches as __ro_after_initAlexey Dobriyan1-2/+2
All kmem caches aren't reallocated once set up. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16skbuff: export mm_[un]account_pinned_pages for other modulesSowmini Varadhan1-2/+4
RDS would like to use the helper functions for managing pinned pages added by Commit a91dbff551a6 ("sock: ulimit on MSG_ZEROCOPY pages") Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-08net: Whitelist the skbuff_head_cache "cb" fieldKees Cook1-1/+3
Most callers of put_cmsg() use a "sizeof(foo)" for the length argument. Within put_cmsg(), a copy_to_user() call is made with a dynamic size, as a result of the cmsg header calculations. This means that hardened usercopy will examine the copy, even though it was technically a fixed size and should be implicitly whitelisted. All the put_cmsg() calls being built from values in skbuff_head_cache are coming out of the protocol-defined "cb" field, so whitelist this field entirely instead of creating per-use bounce buffers, for which there are concerns about performance. Original report was: Bad or missing usercopy whitelist? Kernel memory exposure attempt detected from SLAB object 'skbuff_head_cache' (offset 64, size 16)! WARNING: CPU: 0 PID: 3663 at mm/usercopy.c:81 usercopy_warn+0xdb/0x100 mm/usercopy.c:76 ... __check_heap_object+0x89/0xc0 mm/slab.c:4426 check_heap_object mm/usercopy.c:236 [inline] __check_object_size+0x272/0x530 mm/usercopy.c:259 check_object_size include/linux/thread_info.h:112 [inline] check_copy_size include/linux/thread_info.h:143 [inline] copy_to_user include/linux/uaccess.h:154 [inline] put_cmsg+0x233/0x3f0 net/core/scm.c:242 sock_recv_errqueue+0x200/0x3e0 net/core/sock.c:2913 packet_recvmsg+0xb2e/0x17a0 net/packet/af_packet.c:3296 sock_recvmsg_nosec net/socket.c:803 [inline] sock_recvmsg+0xc9/0x110 net/socket.c:810 ___sys_recvmsg+0x2a4/0x640 net/socket.c:2179 __sys_recvmmsg+0x2a9/0xaf0 net/socket.c:2287 SYSC_recvmmsg net/socket.c:2368 [inline] SyS_recvmmsg+0xc4/0x160 net/socket.c:2352 entry_SYSCALL_64_fastpath+0x29/0xa0 Reported-by: syzbot+e2d6cfb305e9f3911dea@syzkaller.appspotmail.com Fixes: 6d07d1cd300f ("usercopy: Restrict non-usercopy caches to size 0") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-01net: create skb_gso_validate_mac_len()Daniel Axtens1-13/+50
If you take a GSO skb, and split it into packets, will the MAC length (L2 + L3 + L4 headers + payload) of those packets be small enough to fit within a given length? Move skb_gso_mac_seglen() to skbuff.h with other related functions like skb_gso_network_seglen() so we can use it, and then create skb_gso_validate_mac_len to do the full calculation. Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-3/+3
net/ipv6/ip6_gre.c is a case of parallel adds. include/trace/events/tcp.h is a little bit more tricky. The removal of in-trace-macro ifdefs in 'net' paralleled with moving show_tcp_state_name and friends over to include/trace/events/sock.h in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-28skbuff: in skb_copy_ubufs unclone before releasing zerocopyWillem de Bruijn1-3/+3
skb_copy_ubufs must unclone before it is safe to modify its skb_shared_info with skb_zcopy_clear. Commit b90ddd568792 ("skbuff: skb_copy_ubufs must release uarg even without user frags") ensures that all skbs release their zerocopy state, even those without frags. But I forgot an edge case where such an skb arrives that is cloned. The stack does not build such packets. Vhost/tun skbs have their frags orphaned before cloning. TCP skbs only attach zerocopy state when a frag is added. But if TCP packets can be trimmed or linearized, this might occur. Tracing the code I found no instance so far (e.g., skb_linearize ends up calling skb_zcopy_clear if !skb->data_len). Still, it is non-obvious that no path exists. And it is fragile to rely on this. Fixes: b90ddd568792 ("skbuff: skb_copy_ubufs must release uarg even without user frags") Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-27skbuff: in skb_segment, call zerocopy functions once per nskbWillem de Bruijn1-5/+9
This is a net-next follow-up to commit 268b79067942 ("skbuff: orphan frags before zerocopy clone"), which fixed a bug in net, but added a call to skb_zerocopy_clone at each frag to do so. When segmenting skbs with user frags, either the user frags must be replaced with private copies and uarg released, or the uarg must have its refcount increased for each new skb. skb_orphan_frags does the first, except for cases that can handle reference counting. skb_zerocopy_clone then does the second. Call these once per nskb, instead of once per frag. That is, in the common case. With a frag list, also refresh when the origin skb (frag_skb) changes. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21skbuff: skb_copy_ubufs must release uarg even without user fragsWillem de Bruijn1-1/+2
skb_copy_ubufs creates a private copy of frags[] to release its hold on user frags, then calls uarg->callback to notify the owner. Call uarg->callback even when no frags exist. This edge case can happen when zerocopy_sg_from_iter finds enough room in skb_headlen to copy all the data. Fixes: 3ece782693c4 ("sock: skb_copy_ubufs support for compound pages") Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>