user/sven/linux.git/include/linux/skbuff.h, branch v5.4.61

net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build

2020-04-01T09:02:18Z

commit 2c64605b590edadb3fb46d1ec6badb49e940b479 upstream. net/netfilter/nft_fwd_netdev.c: In function ‘nft_fwd_netdev_eval’: net/netfilter/nft_fwd_netdev.c:32:10: error: ‘struct sk_buff’ has no member named ‘tc_redirected’ pkt->skb->tc_redirected = 1; ^~ net/netfilter/nft_fwd_netdev.c:33:10: error: ‘struct sk_buff’ has no member named ‘tc_from_ingress’ pkt->skb->tc_from_ingress = 1; ^~ To avoid a direct dependency with tc actions from netfilter, wrap the redirect bits around CONFIG_NET_REDIRECT and move helpers to include/linux/skbuff.h. Turn on this toggle from the ifb driver, the only existing client of these bits in the tree. This patch adds skb_set_redirected() that sets on the redirected bit on the skbuff, it specifies if the packet was redirect from ingress and resets the timestamp (timestamp reset was originally missing in the netfilter bugfix). Fixes: bcfabee1afd99484 ("netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress") Reported-by: noreply@ellerman.id.au Reported-by: Geert Uytterhoeven Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: add a READ_ONCE() in skb_peek_tail()

2020-01-04T18:18:39Z

commit f8cc62ca3e660ae3fdaee533b1d554297cd2ae82 upstream. skb_peek_tail() can be used without protection of a lock, as spotted by KCSAN [1] In order to avoid load-stearing, add a READ_ONCE() Note that the corresponding WRITE_ONCE() are already there. [1] BUG: KCSAN: data-race in sk_wait_data / skb_queue_tail read to 0xffff8880b36a4118 of 8 bytes by task 20426 on cpu 1: skb_peek_tail include/linux/skbuff.h:1784 [inline] sk_wait_data+0x15b/0x250 net/core/sock.c:2477 kcm_wait_data+0x112/0x1f0 net/kcm/kcmsock.c:1103 kcm_recvmsg+0xac/0x320 net/kcm/kcmsock.c:1130 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_recvmsg+0x92/0xb0 net/socket.c:885 ___sys_recvmsg+0x1a0/0x3e0 net/socket.c:2480 do_recvmmsg+0x19a/0x5c0 net/socket.c:2601 __sys_recvmmsg+0x1ef/0x200 net/socket.c:2680 __do_sys_recvmmsg net/socket.c:2703 [inline] __se_sys_recvmmsg net/socket.c:2696 [inline] __x64_sys_recvmmsg+0x89/0xb0 net/socket.c:2696 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 write to 0xffff8880b36a4118 of 8 bytes by task 451 on cpu 0: __skb_insert include/linux/skbuff.h:1852 [inline] __skb_queue_before include/linux/skbuff.h:1958 [inline] __skb_queue_tail include/linux/skbuff.h:1991 [inline] skb_queue_tail+0x7e/0xc0 net/core/skbuff.c:3145 kcm_queue_rcv_skb+0x202/0x310 net/kcm/kcmsock.c:206 kcm_rcv_strparser+0x74/0x4b0 net/kcm/kcmsock.c:370 __strp_recv+0x348/0xf50 net/strparser/strparser.c:309 strp_recv+0x84/0xa0 net/strparser/strparser.c:343 tcp_read_sock+0x174/0x5c0 net/ipv4/tcp.c:1639 strp_read_sock+0xd4/0x140 net/strparser/strparser.c:366 do_strp_work net/strparser/strparser.c:414 [inline] strp_work+0x9a/0xe0 net/strparser/strparser.c:423 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269 worker_thread+0xa0/0x800 kernel/workqueue.c:2415 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 451 Comm: kworker/u4:3 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: kstrp strp_work Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: Fixed updating of ethertype in skb_mpls_push()

2019-12-18T15:08:56Z

[ Upstream commit d04ac224b1688f005a84f764cfe29844f8e9da08 ] The skb_mpls_push was not updating ethertype of an ethernet packet if the packet was originally received from a non ARPHRD_ETHER device. In the below OVS data path flow, since the device corresponding to port 7 is an l3 device (ARPHRD_NONE) the skb_mpls_push function does not update the ethertype of the packet even though the previous push_eth action had added an ethernet header to the packet. recirc_id(0),in_port(7),eth_type(0x0800),ipv4(tos=0/0xfc,ttl=64,frag=no), actions:push_eth(src=00:00:00:00:00:00,dst=00:00:00:00:00:00), push_mpls(label=13,tc=0,ttl=64,bos=1,eth_type=0x8847),4 Fixes: 8822e270d697 ("net: core: move push MPLS functionality from OvS to core helper") Signed-off-by: Martin Varghese Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Fixed updating of ethertype in function skb_mpls_pop

2019-12-18T15:08:53Z

[ Upstream commit 040b5cfbcefa263ccf2c118c4938308606bb7ed8 ] The skb_mpls_pop was not updating ethertype of an ethernet packet if the packet was originally received from a non ARPHRD_ETHER device. In the below OVS data path flow, since the device corresponding to port 7 is an l3 device (ARPHRD_NONE) the skb_mpls_pop function does not update the ethertype of the packet even though the previous push_eth action had added an ethernet header to the packet. recirc_id(0),in_port(7),eth_type(0x8847), mpls(label=12/0xfffff,tc=0/0,ttl=0/0x0,bos=1/1), actions:push_eth(src=00:00:00:00:00:00,dst=00:00:00:00:00:00), pop_mpls(eth_type=0x800),4 Fixes: ed246cee09b9 ("net: core: move pop MPLS functionality from OvS to core helper") Signed-off-by: Martin Varghese Acked-by: Pravin B Shelar Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

udp: drop skb extensions before marking skb stateless

2019-11-22T17:28:46Z

Once udp stack has set the UDP_SKB_IS_STATELESS flag, later skb free assumes all skb head state has been dropped already. This will leak the extension memory in case the skb has extensions other than the ipsec secpath, e.g. bridge nf data. To fix this, set the UDP_SKB_IS_STATELESS flag only if we don't have extensions or if the extension space can be free'd. Fixes: 895b5c9f206eb7d25dc1360a ("netfilter: drop bridge nf reset from nf_reset") Cc: Paolo Abeni Reported-by: Byron Stanoszek Signed-off-by: Florian Westphal Acked-by: Paolo Abeni Signed-off-by: David S. Miller

net: add skb_queue_empty_lockless()

2019-10-28T20:33:41Z

Some paths call skb_queue_empty() without holding the queue lock. We must use a barrier in order to not let the compiler do strange things, and avoid KCSAN splats. Adding a barrier in skb_queue_empty() might be overkill, I prefer adding a new helper to clearly identify points where the callers might be lockless. This might help us finding real bugs. The corresponding WRITE_ONCE() should add zero cost for current compilers. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net/flow_dissector: switch to siphash

2019-10-24T03:13:22Z

UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet Reported-by: Jonathan Berger Reported-by: Amit Klein Reported-by: Benny Pinkas Cc: Tom Herbert Signed-off-by: David S. Miller

net/sched: fix corrupted L2 header with MPLS 'push' and 'pop' actions

2019-10-16T00:14:48Z

the following script: # tc qdisc add dev eth0 clsact # tc filter add dev eth0 egress protocol ip matchall \ > action mpls push protocol mpls_uc label 0x355aa bos 1 causes corruption of all IP packets transmitted by eth0. On TC egress, we can't rely on the value of skb->mac_len, because it's 0 and a MPLS 'push' operation will result in an overwrite of the first 4 octets in the packet L2 header (e.g. the Destination Address if eth0 is an Ethernet); the same error pattern is present also in the MPLS 'pop' operation. Fix this error in act_mpls data plane, computing 'mac_len' as the difference between the network header and the mac header (when not at TC ingress), and use it in MPLS 'push'/'pop' core functions. v2: unbreak 'make htmldocs' because of missing documentation of 'mac_len' in skb_mpls_pop(), reported by kbuild test robot CC: Lorenzo Bianconi Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC") Reviewed-by: Simon Horman Acked-by: John Hurley Signed-off-by: Davide Caratti Signed-off-by: David S. Miller

netfilter: drop bridge nf reset from nf_reset

2019-10-01T16:42:15Z

commit 174e23810cd31 ("sk_buff: drop all skb extensions on free and skb scrubbing") made napi recycle always drop skb extensions. The additional skb_ext_del() that is performed via nf_reset on napi skb recycle is not needed anymore. Most nf_reset() calls in the stack are there so queued skb won't block 'rmmod nf_conntrack' indefinitely. This removes the skb_ext_del from nf_reset, and renames it to a more fitting nf_reset_ct(). In a few selected places, add a call to skb_ext_reset to make sure that no active extensions remain. I am submitting this for "net", because we're still early in the release cycle. The patch applies to net-next too, but I think the rename causes needless divergence between those trees. Suggested-by: Eric Dumazet Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

sk_buff: drop all skb extensions on free and skb scrubbing

2019-09-27T18:40:19Z

Now that we have a 3rd extension, add a new helper that drops the extension space and use it when we need to scrub an sk_buff. At this time, scrubbing clears secpath and bridge netfilter data, but retains the tc skb extension, after this patch all three get cleared. NAPI reuse/free assumes we can only have a secpath attached to skb, but it seems better to clear all extensions there as well. v2: add unlikely hint (Eric Dumazet) Fixes: 95a7233c452a ("net: openvswitch: Set OvS recirc_id from tc chain index") Signed-off-by: Florian Westphal Signed-off-by: David S. Miller