summaryrefslogtreecommitdiff
path: root/include/linux/skbuff.h
AgeCommit message (Collapse)AuthorFilesLines
2022-10-26io_uring/af_unix: defer registered files gc to io_uring releasePavel Begunkov1-0/+2
[ upstream commit 0091bfc81741b8d3aeb3b7ab8636f911b2de6e80 ] Instead of putting io_uring's registered files in unix_gc() we want it to be done by io_uring itself. The trick here is to consider io_uring registered files for cycle detection but not actually putting them down. Because io_uring can't register other ring instances, this will remove all refs to the ring file triggering the ->release path and clean up with io_ring_ctx_free(). Cc: stable@vger.kernel.org Fixes: 6b06314c47e1 ("io_uring: add file set registration") Reported-and-tested-by: David Bouman <dbouman03@gmail.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> [axboe: add kerneldoc comment to skb, fold in skb leak fix] Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15tcp: TX zerocopy should not sense pfmemalloc statusEric Dumazet1-0/+21
[ Upstream commit 3261400639463a853ba2b3be8bd009c2a8089775 ] We got a recent syzbot report [1] showing a possible misuse of pfmemalloc page status in TCP zerocopy paths. Indeed, for pages coming from user space or other layers, using page_is_pfmemalloc() is moot, and possibly could give false positives. There has been attempts to make page_is_pfmemalloc() more robust, but not using it in the first place in this context is probably better, removing cpu cycles. Note to stable teams : You need to backport 84ce071e38a6 ("net: introduce __skb_fill_page_desc_noacc") as a prereq. Race is more probable after commit c07aea3ef4d4 ("mm: add a signature in struct page") because page_is_pfmemalloc() is now using low order bit from page->lru.next, which can change more often than page->index. Low order bit should never be set for lru.next (when used as an anchor in LRU list), so KCSAN report is mostly a false positive. Backporting to older kernel versions seems not necessary. [1] BUG: KCSAN: data-race in lru_add_fn / tcp_build_frag write to 0xffffea0004a1d2c8 of 8 bytes by task 18600 on cpu 0: __list_add include/linux/list.h:73 [inline] list_add include/linux/list.h:88 [inline] lruvec_add_folio include/linux/mm_inline.h:105 [inline] lru_add_fn+0x440/0x520 mm/swap.c:228 folio_batch_move_lru+0x1e1/0x2a0 mm/swap.c:246 folio_batch_add_and_move mm/swap.c:263 [inline] folio_add_lru+0xf1/0x140 mm/swap.c:490 filemap_add_folio+0xf8/0x150 mm/filemap.c:948 __filemap_get_folio+0x510/0x6d0 mm/filemap.c:1981 pagecache_get_page+0x26/0x190 mm/folio-compat.c:104 grab_cache_page_write_begin+0x2a/0x30 mm/folio-compat.c:116 ext4_da_write_begin+0x2dd/0x5f0 fs/ext4/inode.c:2988 generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3738 ext4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:270 ext4_file_write_iter+0x2e3/0x1210 call_write_iter include/linux/fs.h:2187 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x468/0x760 fs/read_write.c:578 ksys_write+0xe8/0x1a0 fs/read_write.c:631 __do_sys_write fs/read_write.c:643 [inline] __se_sys_write fs/read_write.c:640 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:640 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffffea0004a1d2c8 of 8 bytes by task 18611 on cpu 1: page_is_pfmemalloc include/linux/mm.h:1740 [inline] __skb_fill_page_desc include/linux/skbuff.h:2422 [inline] skb_fill_page_desc include/linux/skbuff.h:2443 [inline] tcp_build_frag+0x613/0xb20 net/ipv4/tcp.c:1018 do_tcp_sendpages+0x3e8/0xaf0 net/ipv4/tcp.c:1075 tcp_sendpage_locked net/ipv4/tcp.c:1140 [inline] tcp_sendpage+0x89/0xb0 net/ipv4/tcp.c:1150 inet_sendpage+0x7f/0xc0 net/ipv4/af_inet.c:833 kernel_sendpage+0x184/0x300 net/socket.c:3561 sock_sendpage+0x5a/0x70 net/socket.c:1054 pipe_to_sendpage+0x128/0x160 fs/splice.c:361 splice_from_pipe_feed fs/splice.c:415 [inline] __splice_from_pipe+0x222/0x4d0 fs/splice.c:559 splice_from_pipe fs/splice.c:594 [inline] generic_splice_sendpage+0x89/0xc0 fs/splice.c:743 do_splice_from fs/splice.c:764 [inline] direct_splice_actor+0x80/0xa0 fs/splice.c:931 splice_direct_to_actor+0x305/0x620 fs/splice.c:886 do_splice_direct+0xfb/0x180 fs/splice.c:974 do_sendfile+0x3bf/0x910 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1303 [inline] __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1303 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x0000000000000000 -> 0xffffea0004a1d288 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 18611 Comm: syz-executor.4 Not tainted 6.0.0-rc2-syzkaller-00248-ge022620b5d05-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Fixes: c07aea3ef4d4 ("mm: add a signature in struct page") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Shakeel Butt <shakeelb@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15net: introduce __skb_fill_page_desc_noaccPavel Begunkov1-11/+17
[ Upstream commit 84ce071e38a6e25ea3ea91188e5482ac1f17b3af ] Managed pages contain pinned userspace pages and controlled by upper layers, there is no need in tracking skb->pfmemalloc for them. Introduce a helper for filling frags but ignoring page tracking, it'll be needed later. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-05bpf: Don't redirect packets with invalid pkt_lenZhengchao Shao1-0/+8
commit fd1894224407c484f652ad456e1ce423e89bb3eb upstream. Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any skbs, that is, the flow->head is null. The root cause, as the [2] says, is because that bpf_prog_test_run_skb() run a bpf prog which redirects empty skbs. So we should determine whether the length of the packet modified by bpf prog or others like bpf_prog_test is valid before forwarding it directly. LINK: [1] https://syzkaller.appspot.com/bug?id=0b84da80c2917757915afa89f7738a9d16ec96c5 LINK: [2] https://www.spinics.net/lists/netdev/msg777503.html Reported-by: syzbot+7a12909485b94426aceb@syzkaller.appspotmail.com Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20220715115559.139691-1-shaozhengchao@huawei.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29net: ipv4: use kfree_skb_reason() in ip_rcv_finish_core()Menglong Dong1-0/+9
[ Upstream commit c1f166d1f7eef212096a98b22f5acf92f9af353d ] Replace kfree_skb() with kfree_skb_reason() in ip_rcv_finish_core(), following drop reasons are introduced: SKB_DROP_REASON_IP_RPFILTER SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29net: ipv4: use kfree_skb_reason() in ip_rcv_core()Menglong Dong1-0/+9
[ Upstream commit 33cba42985c8144eef78d618fc1e51aaa074b169 ] Replace kfree_skb() with kfree_skb_reason() in ip_rcv_core(). Three new drop reasons are introduced: SKB_DROP_REASON_OTHERHOST SKB_DROP_REASON_IP_CSUM SKB_DROP_REASON_IP_INHDR Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29net: netfilter: use kfree_drop_reason() for NF_DROPMenglong Dong1-0/+1
[ Upstream commit 2df3041ba3be950376e8c25a8f6da22f7fcc765c ] Replace kfree_skb() with kfree_skb_reason() in nf_hook_slow() when skb is dropped by reason of NF_DROP. Following new drop reasons are introduced: SKB_DROP_REASON_NETFILTER_DROP Signed-off-by: Menglong Dong <imagedong@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29net: skb_drop_reason: add document for drop reasonsMenglong Dong1-6/+6
[ Upstream commit 88590b369354092183bcba04e2368010c462557f ] Add document for following existing drop reasons: SKB_DROP_REASON_NOT_SPECIFIED SKB_DROP_REASON_NO_SOCKET SKB_DROP_REASON_PKT_TOO_SMALL SKB_DROP_REASON_TCP_CSUM SKB_DROP_REASON_SOCKET_FILTER SKB_DROP_REASON_UDP_CSUM Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29net: socket: rename SKB_DROP_REASON_SOCKET_FILTERMenglong Dong1-1/+1
[ Upstream commit 364df53c081d93fcfd6b91085ff2650c7f17b3c7 ] Rename SKB_DROP_REASON_SOCKET_FILTER, which is used as the reason of skb drop out of socket filter before it's part of a released kernel. It will be used for more protocols than just TCP in future series. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/all/20220127091308.91401-2-imagedong@tencent.com/ Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29net: skb: use kfree_skb_reason() in __udp4_lib_rcv()Menglong Dong1-0/+1
[ Upstream commit 1c7fab70df085d866a3765955f397ca2b4025b15 ] Replace kfree_skb() with kfree_skb_reason() in __udp4_lib_rcv. New drop reason 'SKB_DROP_REASON_UDP_CSUM' is added for udp csum error. Signed-off-by: Menglong Dong <imagedong@tencent.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29net: skb: use kfree_skb_reason() in tcp_v4_rcv()Menglong Dong1-0/+4
[ Upstream commit 85125597419aec3aa7b8f3b8713e415f997796f2 ] Replace kfree_skb() with kfree_skb_reason() in tcp_v4_rcv(). Following drop reasons are added: SKB_DROP_REASON_NO_SOCKET SKB_DROP_REASON_PKT_TOO_SMALL SKB_DROP_REASON_TCP_CSUM SKB_DROP_REASON_TCP_FILTER After this patch, 'kfree_skb' event will print message like this: $ TASK-PID CPU# ||||| TIMESTAMP FUNCTION $ | | | ||||| | | <idle>-0 [000] ..s1. 36.113438: kfree_skb: skbaddr=(____ptrval____) protocol=2048 location=(____ptrval____) reason: NO_SOCKET The reason of skb drop is printed too. Signed-off-by: Menglong Dong <imagedong@tencent.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29net: skb: introduce kfree_skb_reason()Menglong Dong1-1/+22
[ Upstream commit c504e5c2f9648a1e5c2be01e8c3f59d394192bd3 ] Introduce the interface kfree_skb_reason(), which is able to pass the reason why the skb is dropped to 'kfree_skb' tracepoint. Add the 'reason' field to 'trace_kfree_skb', therefor user can get more detail information about abnormal skb with 'drop_monitor' or eBPF. All drop reasons are defined in the enum 'skb_drop_reason', and they will be print as string in 'kfree_skb' tracepoint in format of 'reason: XXX'. ( Maybe the reasons should be defined in a uapi header file, so that user space can use them? ) Signed-off-by: Menglong Dong <imagedong@tencent.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08net: preserve skb_end_offset() in skb_unclone_keeptruesize()Eric Dumazet1-9/+9
commit 2b88cba55883eaafbc9b7cbff0b2c7cdba71ed01 upstream. syzbot found another way to trigger the infamous WARN_ON_ONCE(delta < len) in skb_try_coalesce() [1] I was able to root cause the issue to kfence. When kfence is in action, the following assertion is no longer true: int size = xxxx; void *ptr1 = kmalloc(size, gfp); void *ptr2 = kmalloc(size, gfp); if (ptr1 && ptr2) ASSERT(ksize(ptr1) == ksize(ptr2)); We attempted to fix these issues in the blamed commits, but forgot that TCP was possibly shifting data after skb_unclone_keeptruesize() has been used, notably from tcp_retrans_try_collapse(). So we not only need to keep same skb->truesize value, we also need to make sure TCP wont fill new tailroom that pskb_expand_head() was able to get from a addr = kmalloc(...) followed by ksize(addr) Split skb_unclone_keeptruesize() into two parts: 1) Inline skb_unclone_keeptruesize() for the common case, when skb is not cloned. 2) Out of line __skb_unclone_keeptruesize() for the 'slow path'. WARNING: CPU: 1 PID: 6490 at net/core/skbuff.c:5295 skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295 Modules linked in: CPU: 1 PID: 6490 Comm: syz-executor161 Not tainted 5.17.0-rc4-syzkaller-00229-g4f12b742eb2b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295 Code: bf 01 00 00 00 0f b7 c0 89 c6 89 44 24 20 e8 62 24 4e fa 8b 44 24 20 83 e8 01 0f 85 e5 f0 ff ff e9 87 f4 ff ff e8 cb 20 4e fa <0f> 0b e9 06 f9 ff ff e8 af b2 95 fa e9 69 f0 ff ff e8 95 b2 95 fa RSP: 0018:ffffc900063af268 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 00000000ffffffd5 RCX: 0000000000000000 RDX: ffff88806fc05700 RSI: ffffffff872abd55 RDI: 0000000000000003 RBP: ffff88806e675500 R08: 00000000ffffffd5 R09: 0000000000000000 R10: ffffffff872ab659 R11: 0000000000000000 R12: ffff88806dd554e8 R13: ffff88806dd9bac0 R14: ffff88806dd9a2c0 R15: 0000000000000155 FS: 00007f18014f9700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020002000 CR3: 000000006be7a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> tcp_try_coalesce net/ipv4/tcp_input.c:4651 [inline] tcp_try_coalesce+0x393/0x920 net/ipv4/tcp_input.c:4630 tcp_queue_rcv+0x8a/0x6e0 net/ipv4/tcp_input.c:4914 tcp_data_queue+0x11fd/0x4bb0 net/ipv4/tcp_input.c:5025 tcp_rcv_established+0x81e/0x1ff0 net/ipv4/tcp_input.c:5947 tcp_v4_do_rcv+0x65e/0x980 net/ipv4/tcp_ipv4.c:1719 sk_backlog_rcv include/net/sock.h:1037 [inline] __release_sock+0x134/0x3b0 net/core/sock.c:2779 release_sock+0x54/0x1b0 net/core/sock.c:3311 sk_wait_data+0x177/0x450 net/core/sock.c:2821 tcp_recvmsg_locked+0xe28/0x1fd0 net/ipv4/tcp.c:2457 tcp_recvmsg+0x137/0x610 net/ipv4/tcp.c:2572 inet_recvmsg+0x11b/0x5e0 net/ipv4/af_inet.c:850 sock_recvmsg_nosec net/socket.c:948 [inline] sock_recvmsg net/socket.c:966 [inline] sock_recvmsg net/socket.c:962 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632 ___sys_recvmsg+0x127/0x200 net/socket.c:2674 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: c4777efa751d ("net: add and use skb_unclone_keeptruesize() helper") Fixes: 097b9146c0e2 ("net: fix up truesize of cloned skb in skb_prepare_for_shift()") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Marco Elver <elver@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-08net: add skb_set_end_offset() helperEric Dumazet1-0/+10
commit 763087dab97547230a6807c865a6a5ae53a59247 upstream. We have multiple places where this helper is convenient, and plan using it in the following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27net: openvswitch: Fix ct_state nat flags for conns arriving from tcPaul Blakey1-1/+3
[ Upstream commit 6f022c2ddbcefaee79502ce5386dfe351d457070 ] Netfilter conntrack maintains NAT flags per connection indicating whether NAT was configured for the connection. Openvswitch maintains NAT flags on the per packet flow key ct_state field, indicating whether NAT was actually executed on the packet. When a packet misses from tc to ovs the conntrack NAT flags are set. However, NAT was not necessarily executed on the packet because the connection's state might still be in NEW state. As such, openvswitch wrongly assumes that NAT was executed and sets an incorrect flow key NAT flags. Fix this, by flagging to openvswitch which NAT was actually done in act_ct via tc_skb_ext and tc_skb_cb to the openvswitch module, so the packet flow key NAT flags will be correctly set. Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct") Signed-off-by: Paul Blakey <paulb@nvidia.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://lore.kernel.org/r/20220106153804.26451-1-paulb@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27net: openvswitch: Fix matching zone id for invalid conns arriving from tcPaul Blakey1-0/+1
[ Upstream commit 635d448a1cce4b4ebee52b351052c70434fa90ea ] Zone id is not restored if we passed ct and ct rejected the connection, as there is no ct info on the skb. Save the zone from tc skb cb to tc skb extension and pass it on to ovs, use that info to restore the zone id for invalid connections. Fixes: d29334c15d33 ("net/sched: act_api: fix miss set post_ct for ovs after do conntrack in act_ct") Signed-off-by: Paul Blakey <paulb@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27net/sched: flow_dissector: Fix matching on zone id for invalid connsPaul Blakey1-1/+1
[ Upstream commit 3849595866166b23bf6a0cb9ff87e06423167f67 ] If ct rejects a flow, it removes the conntrack info from the skb. act_ct sets the post_ct variable so the dissector will see this case as an +tracked +invalid state, but the zone id is lost with the conntrack info. To restore the zone id on such cases, set the last executed zone, via the tc control block, when passing ct, and read it back in the dissector if there is no ct info on the skb (invalid connection). Fixes: 7baf2429a1a9 ("net/sched: cls_flower add CT_FLAGS_INVALID flag support") Signed-off-by: Paul Blakey <paulb@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-25net: add and use skb_unclone_keeptruesize() helperEric Dumazet1-0/+16
commit c4777efa751d293e369aec464ce6875e957be255 upstream. While commit 097b9146c0e2 ("net: fix up truesize of cloned skb in skb_prepare_for_shift()") fixed immediate issues found when KFENCE was enabled/tested, there are still similar issues, when tcp_trim_head() hits KFENCE while the master skb is cloned. This happens under heavy networking TX workloads, when the TX completion might be delayed after incoming ACK. This patch fixes the WARNING in sk_stream_kill_queues when sk->sk_mem_queued/sk->sk_forward_alloc are not zero. Fixes: d3fb45f370d9 ("mm, kfence: insert KFENCE hooks for SLAB") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Marco Elver <elver@google.com> Link: https://lore.kernel.org/r/20211102004555.1359210-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-09net/af_unix: fix a data-race in unix_dgram_pollEric Dumazet1-1/+1
syzbot reported another data-race in af_unix [1] Lets change __skb_insert() to use WRITE_ONCE() when changing skb head qlen. Also, change unix_dgram_poll() to use lockless version of unix_recvq_full() It is verry possible we can switch all/most unix_recvq_full() to the lockless version, this will be done in a future kernel version. [1] HEAD commit: 8596e589b787732c8346f0482919e83cc9362db1 BUG: KCSAN: data-race in skb_queue_tail / unix_dgram_poll write to 0xffff88814eeb24e0 of 4 bytes by task 25815 on cpu 0: __skb_insert include/linux/skbuff.h:1938 [inline] __skb_queue_before include/linux/skbuff.h:2043 [inline] __skb_queue_tail include/linux/skbuff.h:2076 [inline] skb_queue_tail+0x80/0xa0 net/core/skbuff.c:3264 unix_dgram_sendmsg+0xff2/0x1600 net/unix/af_unix.c:1850 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg net/socket.c:723 [inline] ____sys_sendmsg+0x360/0x4d0 net/socket.c:2392 ___sys_sendmsg net/socket.c:2446 [inline] __sys_sendmmsg+0x315/0x4b0 net/socket.c:2532 __do_sys_sendmmsg net/socket.c:2561 [inline] __se_sys_sendmmsg net/socket.c:2558 [inline] __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2558 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88814eeb24e0 of 4 bytes by task 25834 on cpu 1: skb_queue_len include/linux/skbuff.h:1869 [inline] unix_recvq_full net/unix/af_unix.c:194 [inline] unix_dgram_poll+0x2bc/0x3e0 net/unix/af_unix.c:2777 sock_poll+0x23e/0x260 net/socket.c:1288 vfs_poll include/linux/poll.h:90 [inline] ep_item_poll fs/eventpoll.c:846 [inline] ep_send_events fs/eventpoll.c:1683 [inline] ep_poll fs/eventpoll.c:1798 [inline] do_epoll_wait+0x6ad/0xf00 fs/eventpoll.c:2226 __do_sys_epoll_wait fs/eventpoll.c:2238 [inline] __se_sys_epoll_wait fs/eventpoll.c:2233 [inline] __x64_sys_epoll_wait+0xf6/0x120 fs/eventpoll.c:2233 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x0000001b -> 0x00000001 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 25834 Comm: syz-executor.1 Tainted: G W 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 86b18aaa2b5b ("skbuff: fix a data race in skb_queue_len()") Cc: Qian Cai <cai@lca.pw> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-10page_pool: keep pp info as long as page pool owns the pageYunsheng Lin1-3/+1
Currently, page->pp is cleared and set everytime the page is recycled, which is unnecessary. So only set the page->pp when the page is added to the page pool and only clear it when the page is released from the page pool. This is also a preparation to support allocating frag page in page pool. Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-03skbuff: introduce skb_expand_head()Vasily Averin1-0/+1
Like skb_realloc_headroom(), new helper increases headroom of specified skb. Unlike skb_realloc_headroom(), it does not allocate a new skb if possible; copies skb->sk on new skb when as needed and frees original skb in case of failures. This helps to simplify ip[6]_finish_output2() and a few other similar cases. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-30sk_buff: avoid potentially clearing 'slow_gro' fieldPaolo Abeni1-1/+1
If skb_dst_set_noref() is invoked with a NULL dst, the 'slow_gro' field is cleared, too. That could lead to wrong behavior if the skb later enters the GRO stage. Fix the potential issue replacing preserving a non-zero value of the 'slow_gro' field. Additionally, fix a comment typo. Reported-by: Sabrina Dubroca <sd@queasysnail.net> Reported-by: Jakub Kicinski <kuba@kernel.org> Fixes: 8a886b142bd0 ("sk_buff: track dst status in slow_gro") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/aa42529252dc8bb02bd42e8629427040d1058537.1627662501.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-29sk_buff: track dst status in slow_groPaolo Abeni1-0/+2
Similar to the previous patch, but covering the dst field: the slow_gro flag is additionally set when a dst is attached to the skb RFC -> v1: - use the existing flag instead of adding a new one Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29sk_buff: introduce 'slow_gro' flagsPaolo Abeni1-0/+4
The new flag tracks if any state field is set, so that GRO requires 'unusual'/slow prepare steps. Set such flag when a ct entry is attached to the skb, and never clear it. The new bit uses an existing hole into the sk_buff struct RFC -> v1: - use a single state bit, never clear it - avoid moving the _nfct field Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-08bpf: cpumap: Implement generic cpumapKumar Kartikeya Dwivedi1-8/+2
This change implements CPUMAP redirect support for generic XDP programs. The idea is to reuse the cpu map entry's queue that is used to push native xdp frames for redirecting skb to a different CPU. This will match native XDP behavior (in that RPS is invoked again for packet reinjected into networking stack). To be able to determine whether the incoming skb is from the driver or cpumap, we reuse skb->redirected bit that skips generic XDP processing when it is set. To always make use of this, CONFIG_NET_REDIRECT guard on it has been lifted and it is always available. >From the redirect side, we add the skb to ptr_ring with its lowest bit set to 1. This should be safe as skb is not 1-byte aligned. This allows kthread to discern between xdp_frames and sk_buff. On consumption of the ptr_ring item, the lowest bit is unset. In the end, the skb is simply added to the list that kthread is anyway going to maintain for xdp_frames converted to skb, and then received again by using netif_receive_skb_list. Bulking optimization for generic cpumap is left as an exercise for a future patch for now. Since cpumap entry progs are now supported, also remove check in generic_xdp_install for the cpumap. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/20210702111825.491065-4-memxor@gmail.com
2021-06-08page_pool: Allow drivers to hint on SKB recyclingIlias Apalodimas1-3/+30
Up to now several high speed NICs have custom mechanisms of recycling the allocated memory they use for their payloads. Our page_pool API already has recycling capabilities that are always used when we are running in 'XDP mode'. So let's tweak the API and the kernel network stack slightly and allow the recycling to happen even during the standard operation. The API doesn't take into account 'split page' policies used by those drivers currently, but can be extended once we have users for that. The idea is to be able to intercept the packet on skb_release_data(). If it's a buffer coming from our page_pool API recycle it back to the pool for further usage or just release the packet entirely. To achieve that we introduce a bit in struct sk_buff (pp_recycle:1) and a field in struct page (page->pp) to store the page_pool pointer. Storing the information in page->pp allows us to recycle both SKBs and their fragments. We could have skipped the skb bit entirely, since identical information can bederived from struct page. However, in an effort to affect the free path as less as possible, reading a single bit in the skb which is already in cache, is better that trying to derive identical information for the page stored data. The driver or page_pool has to take care of the sync operations on it's own during the buffer recycling since the buffer is, after opting-in to the recycling, never unmapped. Since the gain on the drivers depends on the architecture, we are not enabling recycling by default if the page_pool API is used on a driver. In order to enable recycling the driver must call skb_mark_for_recycle() to store the information we need for recycling in page->pp and enabling the recycling bit, or page_pool_store_mem_info() for a fragment. Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Co-developed-by: Matteo Croce <mcroce@microsoft.com> Signed-off-by: Matteo Croce <mcroce@microsoft.com> Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-08skbuff: add a parameter to __skb_frag_unrefMatteo Croce1-3/+5
This is a prerequisite patch, the next one is enabling recycling of skbs and fragments. Add an extra argument on __skb_frag_unref() to handle recycling, and update the current users of the function with that. Signed-off-by: Matteo Croce <mcroce@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-01net: Introduce skb_send_sock() for sock_mapCong Wang1-0/+1
We only have skb_send_sock_locked() which requires callers to use lock_sock(). Introduce a variant skb_send_sock() which locks on its own, callers do not need to lock it any more. This will save us from adding a ->sendmsg_locked for each protocol. To reuse the code, pass function pointers to __skb_send_sock() and build skb_send_sock() and skb_send_sock_locked() on top. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210331023237.41094-4-xiyou.wangcong@gmail.com
2021-03-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-0/+1
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-17net/sched: act_api: fix miss set post_ct for ovs after do conntrack in act_ctwenxu1-0/+1
When openvswitch conntrack offload with act_ct action. The first rule do conntrack in the act_ct in tc subsystem. And miss the next rule in the tc and fallback to the ovs datapath but miss set post_ct flag which will lead the ct_state_key with -trk flag. Fixes: 7baf2429a1a9 ("net/sched: cls_flower add CT_FLAGS_INVALID flag support") Signed-off-by: wenxu <wenxu@ucloud.cn> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-15skbuff: micro-optimize {,__}skb_header_pointer()Alexander Lobakin1-3/+2
{,__}skb_header_pointer() helpers exist mainly for preventing accesses-beyond-end of the linear data. In the vast majorify of cases, they bail out on the first condition. All code going after is mostly a fallback. Mark the most common branch as 'likely' one to move it in-line. Also, skb_copy_bits() can return negative values only when the input arguments are invalid, e.g. offset is greater than skb->len. It can be safely marked as 'unlikely' branch, assuming that hotpath code provides sane input to not fail here. These two bump the throughput with a single Flow Dissector pass on every packet (e.g. with RPS or driver that uses eth_get_headlen()) on 20 Mbps per flow/core. Signed-off-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-15flow_dissector: constify raw input data argumentAlexander Lobakin1-8/+7
Flow Dissector code never modifies the input buffer, neither skb nor raw data. Make 'data' argument const for all of the Flow dissector's functions. Signed-off-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-15skbuff: make __skb_header_pointer()'s data argument constAlexander Lobakin1-3/+3
The function never modifies the input buffer, so 'data' argument can be marked as const. This implies one harmless cast-away. Signed-off-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-12tcp: plug skb_still_in_host_queue() to TSQEric Dumazet1-1/+1
Jakub and Neil reported an increase of RTO timers whenever TX completions are delayed a bit more (by increasing NIC TX coalescing parameters) Main issue is that TCP stack has a logic preventing a packet being retransmit if the prior clone has not yet been orphaned or freed. This logic came with commit 1f3279ae0c13 ("tcp: avoid retransmits of TCP packets hanging in host queues") Thankfully, in the case skb_still_in_host_queue() detects the initial clone is still in flight, it can use TSQ logic that will eventually retry later, at the moment the clone is freed or orphaned. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Neil Spring <ntspring@fb.com> Reported-by: Jakub Kicinski <kuba@kernel.org> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-04skmsg: Add function doc for skb->_sk_redirCong Wang1-0/+1
This should fix the following warning: include/linux/skbuff.h:932: warning: Function parameter or member '_sk_redir' not described in 'sk_buff' Reported-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Lorenz Bauer <lmb@cloudflare.com> Link: https://lore.kernel.org/bpf/20210301184805.8174-1-xiyou.wangcong@gmail.com
2021-02-26skmsg: Move sk_redir from TCP_SKB_CB to skbCong Wang1-0/+3
Currently TCP_SKB_CB() is hard-coded in skmsg code, it certainly does not work for any other non-TCP protocols. We can move them to skb ext, but it introduces a memory allocation on fast path. Fortunately, we only need to a word-size to store all the information, because the flags actually only contains 1 bit so can be just packed into the lowest bit of the "pointer", which is stored as unsigned long. Inside struct sk_buff, '_skb_refdst' can be reused because skb dst is no longer needed after ->sk_data_ready() so we can just drop it. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-5-xiyou.wangcong@gmail.com
2021-02-14skbuff: queue NAPI_MERGED_FREE skbs into NAPI cache instead of freeingAlexander Lobakin1-0/+1
napi_frags_finish() and napi_skb_finish() can only be called inside NAPI Rx context, so we can feed NAPI cache with skbuff_heads that got NAPI_MERGED_FREE verdict instead of immediate freeing. Replace __kfree_skb() with __kfree_skb_defer() in napi_skb_finish() and move napi_skb_free_stolen_head() to skbuff.c, so it can drop skbs to NAPI cache. As many drivers call napi_alloc_skb()/napi_get_frags() on their receive path, this becomes especially useful. Signed-off-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-14skbuff: introduce {,__}napi_build_skb() which reuses NAPI cache headsAlexander Lobakin1-0/+2
Instead of just bulk-flushing skbuff_heads queued up through napi_consume_skb() or __kfree_skb_defer(), try to reuse them on allocation path. If the cache is empty on allocation, bulk-allocate the first 16 elements, which is more efficient than per-skb allocation. If the cache is full on freeing, bulk-wipe the second half of the cache (32 elements). This also includes custom KASAN poisoning/unpoisoning to be double sure there are no use-after-free cases. To not change current behaviour, introduce a new function, napi_build_skb(), to optionally use a new approach later in drivers. Note on selected bulk size, 16: - this equals to XDP_BULK_QUEUE_SIZE, DEV_MAP_BULK_SIZE and especially VETH_XDP_BATCH, which is also used to bulk-allocate skbuff_heads and was tested on powerful setups; - this also showed the best performance in the actual test series (from the array of {8, 16, 32}). Suggested-by: Edward Cree <ecree.xilinx@gmail.com> # Divide on two halves Suggested-by: Eric Dumazet <edumazet@google.com> # KASAN poisoning Cc: Dmitry Vyukov <dvyukov@google.com> # Help with KASAN Cc: Paolo Abeni <pabeni@redhat.com> # Reduced batch size Signed-off-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-14skbuff: remove __kfree_skb_flush()Alexander Lobakin1-1/+0
This function isn't much needed as NAPI skb queue gets bulk-freed anyway when there's no more room, and even may reduce the efficiency of bulk operations. It will be even less needed after reusing skb cache on allocation path, so remove it and this way lighten network softirqs a bit. Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-06net: Introduce {netdev,napi}_alloc_frag_align()Kevin Hao1-2/+34
In the current implementation of {netdev,napi}_alloc_frag(), it doesn't have any align guarantee for the returned buffer address, But for some hardwares they do require the DMA buffer to be aligned correctly, so we would have to use some workarounds like below if the buffers allocated by the {netdev,napi}_alloc_frag() are used by these hardwares for DMA. buf = napi_alloc_frag(really_needed_size + align); buf = PTR_ALIGN(buf, align); These codes seems ugly and would waste a lot of memories if the buffers are used in a network driver for the TX/RX. We have added the align support for the page_frag functions, so add the corresponding {netdev,napi}_frag functions. Signed-off-by: Kevin Hao <haokexin@gmail.com> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-05net: introduce common dev_page_is_reusable()Alexander Lobakin1-0/+16
A bunch of drivers test the page before reusing/recycling for two common conditions: - if a page was allocated under memory pressure (pfmemalloc page); - if a page was allocated at a distant memory node (to exclude slowdowns). Introduce a new common inline for doing this, with likely() already folded inside to make driver code a bit simpler. Suggested-by: David Rientjes <rientjes@google.com> Suggested-by: Jakub Kicinski <kuba@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Alexander Lobakin <alobakin@pm.me> Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-05skbuff: constify skb_propagate_pfmemalloc() "page" argumentAlexander Lobakin1-2/+2
The function doesn't write anything to the page struct itself, so this argument can be const. Misc: align second argument to the brace while at it. Signed-off-by: Alexander Lobakin <alobakin@pm.me> Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-23tcp: add TTL to SCM_TIMESTAMPING_OPT_STATSYousuk Seung1-1/+1
This patch adds TCP_NLA_TTL to SCM_TIMESTAMPING_OPT_STATS that exports the time-to-live or hop limit of the latest incoming packet with SCM_TSTAMP_ACK. The value exported may not be from the packet that acks the sequence when incoming packets are aggregated. Exporting the time-to-live or hop limit value of incoming packets helps to estimate the hop count of the path of the flow that may change over time. Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Link: https://lore.kernel.org/r/20210120204155.552275-1-ysseung@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-21net/sched: cls_flower add CT_FLAGS_INVALID flag supportwenxu1-2/+2
This patch add the TCA_FLOWER_KEY_CT_FLAGS_INVALID flag to match the ct_state with invalid for conntrack. Signed-off-by: wenxu <wenxu@ucloud.cn> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Link: https://lore.kernel.org/r/1611045110-682-1-git-send-email-wenxu@ucloud.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-20net: add inline function skb_csum_is_sctpXin Long1-0/+5
This patch is to define a inline function skb_csum_is_sctp(), and also replace all places where it checks if it's a SCTP CSUM skb. This function would be used later in many networking drivers in the following patches. Suggested-by: Alexander Duyck <alexander.duyck@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+2
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-12net: compound page support in skb_seq_readWillem de Bruijn1-0/+1
skb_seq_read iterates over an skb, returning pointer and length of the next data range with each call. It relies on kmap_atomic to access highmem pages when needed. An skb frag may be backed by a compound page, but kmap_atomic maps only a single page. There are not enough kmap slots to always map all pages concurrently. Instead, if kmap_atomic is needed, iterate over each page. As this increases the number of calls, avoid this unless needed. The necessary condition is captured in skb_frag_must_loop. I tried to make the change as obvious as possible. It should be easy to verify that nothing changes if skb_frag_must_loop returns false. Tested: On an x86 platform with CONFIG_HIGHMEM=y CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP=y CONFIG_NETFILTER_XT_MATCH_STRING=y Run ip link set dev lo mtu 1500 iptables -A OUTPUT -m string --string 'badstring' -algo bm -j ACCEPT dd if=/dev/urandom of=in bs=1M count=20 nc -l -p 8000 > /dev/null & nc -w 1 -q 0 localhost 8000 < in Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-12net: support kmap_local forced debugging in skb_frag_foreachWillem de Bruijn1-1/+1
Skb frags may be backed by highmem and/or compound pages. Highmem pages need kmap_atomic mappings to access. But kmap_atomic maps a single page, not the entire compound page. skb_foreach_page iterates over an skb frag, in one step in the common case, page by page only if kmap_atomic must be called for each page. The decision logic is captured in skb_frag_must_loop. CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP extends kmap from highmem to all pages, to increase code coverage. Extend skb_frag_must_loop to this new condition. Link: https://lore.kernel.org/linux-mm/20210106180132.41dc249d@gandalf.local.home/ Fixes: 0e91a0c6984c ("mm/highmem: Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP") Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Willem de Bruijn <willemb@google.com> Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-08skbuff: Rename skb_zcopy_{get|put} to net_zcopy_{get|put}Jonathan Lemon1-5/+5
Unlike the rest of the skb_zcopy_ functions, these routines operate on a 'struct ubuf', not a skb. Remove the 'skb_' prefix from the naming to make things clearer. Suggested-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-08tap/tun: add skb_zcopy_init() helper for initialization.Jonathan Lemon1-2/+7
Replace direct assignments with skb_zcopy_init() for zerocopy cases where a new skb is initialized, without changing the reference counts. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
generated by cgit v1.2.3 (git 2.39.0) at 2025-08-24 12:26:17 +0300