kernel/net/sched, branch linux-5.1.y

net: sched: verify that q!=NULL before setting q->flags

2019-07-28T06:28:38Z

commit 503d81d428bd598430f7f9d02021634e1a8139a0 upstream. In function int tc_new_tfilter() q pointer can be NULL when adding filter on a shared block. With recent change that resets TCQ_F_CAN_BYPASS after filter creation, following NULL pointer dereference happens in case parent block is shared: [ 212.925060] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 212.925445] #PF: supervisor write access in kernel mode [ 212.925709] #PF: error_code(0x0002) - not-present page [ 212.925965] PGD 8000000827923067 P4D 8000000827923067 PUD 827924067 PMD 0 [ 212.926302] Oops: 0002 [#1] SMP KASAN PTI [ 212.926539] CPU: 18 PID: 2617 Comm: tc Tainted: G B 5.2.0+ #512 [ 212.926938] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 212.927364] RIP: 0010:tc_new_tfilter+0x698/0xd40 [ 212.927633] Code: 74 0d 48 85 c0 74 08 48 89 ef e8 03 aa 62 00 48 8b 84 24 a0 00 00 00 48 8d 78 10 48 89 44 24 18 e8 4d 0c 6b ff 48 8b 44 24 18 <83> 60 10 f b 48 85 ed 0f 85 3d fe ff ff e9 4f fe ff ff e8 81 26 f8 [ 212.928607] RSP: 0018:ffff88884fd5f5d8 EFLAGS: 00010296 [ 212.928905] RAX: 0000000000000000 RBX: 0000000000000000 RCX: dffffc0000000000 [ 212.929201] RDX: 0000000000000007 RSI: 0000000000000004 RDI: 0000000000000297 [ 212.929402] RBP: ffff88886bedd600 R08: ffffffffb91d4b51 R09: fffffbfff7616e4d [ 212.929609] R10: fffffbfff7616e4c R11: ffffffffbb0b7263 R12: ffff88886bc61040 [ 212.929803] R13: ffff88884fd5f950 R14: ffffc900039c5000 R15: ffff88835e927680 [ 212.929999] FS: 00007fe7c50b6480(0000) GS:ffff88886f980000(0000) knlGS:0000000000000000 [ 212.930235] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 212.930394] CR2: 0000000000000010 CR3: 000000085bd04002 CR4: 00000000001606e0 [ 212.930588] Call Trace: [ 212.930682] ? tc_del_tfilter+0xa40/0xa40 [ 212.930811] ? __lock_acquire+0x5b5/0x2460 [ 212.930948] ? find_held_lock+0x85/0xa0 [ 212.931081] ? tc_del_tfilter+0xa40/0xa40 [ 212.931201] rtnetlink_rcv_msg+0x4ab/0x5f0 [ 212.931332] ? rtnl_dellink+0x490/0x490 [ 212.931454] ? lockdep_hardirqs_on+0x260/0x260 [ 212.931589] ? netlink_deliver_tap+0xab/0x5a0 [ 212.931717] ? match_held_lock+0x1b/0x240 [ 212.931844] netlink_rcv_skb+0xd0/0x200 [ 212.931958] ? rtnl_dellink+0x490/0x490 [ 212.932079] ? netlink_ack+0x440/0x440 [ 212.932205] ? netlink_deliver_tap+0x161/0x5a0 [ 212.932335] ? lock_downgrade+0x360/0x360 [ 212.932457] ? lock_acquire+0xe5/0x210 [ 212.932579] netlink_unicast+0x296/0x350 [ 212.932705] ? netlink_attachskb+0x390/0x390 [ 212.932834] ? _copy_from_iter_full+0xe0/0x3a0 [ 212.932976] netlink_sendmsg+0x394/0x600 [ 212.937998] ? netlink_unicast+0x350/0x350 [ 212.943033] ? move_addr_to_kernel.part.0+0x90/0x90 [ 212.948115] ? netlink_unicast+0x350/0x350 [ 212.953185] sock_sendmsg+0x96/0xa0 [ 212.958099] ___sys_sendmsg+0x482/0x520 [ 212.962881] ? match_held_lock+0x1b/0x240 [ 212.967618] ? copy_msghdr_from_user+0x250/0x250 [ 212.972337] ? lock_downgrade+0x360/0x360 [ 212.976973] ? rwlock_bug.part.0+0x60/0x60 [ 212.981548] ? __mod_node_page_state+0x1f/0xa0 [ 212.986060] ? match_held_lock+0x1b/0x240 [ 212.990567] ? find_held_lock+0x85/0xa0 [ 212.994989] ? do_user_addr_fault+0x349/0x5b0 [ 212.999387] ? lock_downgrade+0x360/0x360 [ 213.003713] ? find_held_lock+0x85/0xa0 [ 213.007972] ? __fget_light+0xa1/0xf0 [ 213.012143] ? sockfd_lookup_light+0x91/0xb0 [ 213.016165] __sys_sendmsg+0xba/0x130 [ 213.020040] ? __sys_sendmsg_sock+0xb0/0xb0 [ 213.023870] ? handle_mm_fault+0x337/0x470 [ 213.027592] ? page_fault+0x8/0x30 [ 213.031316] ? lockdep_hardirqs_off+0xbe/0x100 [ 213.034999] ? mark_held_locks+0x24/0x90 [ 213.038671] ? do_syscall_64+0x1e/0xe0 [ 213.042297] do_syscall_64+0x74/0xe0 [ 213.045828] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 213.049354] RIP: 0033:0x7fe7c527c7b8 [ 213.052792] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f 0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 54 [ 213.060269] RSP: 002b:00007ffc3f7908a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 213.064144] RAX: ffffffffffffffda RBX: 000000005d34716f RCX: 00007fe7c527c7b8 [ 213.068094] RDX: 0000000000000000 RSI: 00007ffc3f790910 RDI: 0000000000000003 [ 213.072109] RBP: 0000000000000000 R08: 0000000000000001 R09: 00007fe7c5340cc0 [ 213.076113] R10: 0000000000404ec2 R11: 0000000000000246 R12: 0000000000000080 [ 213.080146] R13: 0000000000480640 R14: 0000000000000080 R15: 0000000000000000 [ 213.084147] Modules linked in: act_gact cls_flower sch_ingress nfsv3 nfs_acl nfs lockd grace fscache bridge stp llc sunrpc intel_rapl_msr intel_rapl_common [<1;69;32Msb_edac rdma_ucm rdma_cm x86_pkg_temp_thermal iw_cm intel_powerclamp ib_cm coretemp kvm_intel kvm irqbypass mlx5_ib ib_uverbs ib_core crct10dif_pclmul crc32_pc lmul crc32c_intel ghash_clmulni_intel mlx5_core intel_cstate intel_uncore iTCO_wdt igb iTCO_vendor_support mlxfw mei_me ptp ses intel_rapl_perf mei pcspkr ipmi _ssif i2c_i801 joydev enclosure pps_core lpc_ich ioatdma wmi dca ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter acpi_pad ast i2c_algo_bit drm_vram_helpe r ttm drm_kms_helper drm mpt3sas raid_class scsi_transport_sas [ 213.112326] CR2: 0000000000000010 [ 213.117429] ---[ end trace adb58eb0a4ee6283 ]--- Verify that q pointer is not NULL before setting the 'flags' field. Fixes: 3f05e6886a59 ("net_sched: unset TCQ_F_CAN_BYPASS when adding filters") Signed-off-by: Vlad Buslov Acked-by: Jiri Pirko Signed-off-by: David S. Miller Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman

net_sched: unset TCQ_F_CAN_BYPASS when adding filters

2019-07-28T06:28:29Z

[ Upstream commit 3f05e6886a595c9a29a309c52f45326be917823c ] For qdisc's that support TC filters and set TCQ_F_CAN_BYPASS, notably fq_codel, it makes no sense to let packets bypass the TC filters we setup in any scenario, otherwise our packets steering policy could not be enforced. This can be reproduced easily with the following script: ip li add dev dummy0 type dummy ifconfig dummy0 up tc qd add dev dummy0 root fq_codel tc filter add dev dummy0 parent 8001: protocol arp basic action mirred egress redirect dev lo tc filter add dev dummy0 parent 8001: protocol ip basic action mirred egress redirect dev lo ping -I dummy0 192.168.112.1 Without this patch, packets are sent directly to dummy0 without hitting any of the filters. With this patch, packets are redirected to loopback as expected. This fix is not perfect, it only unsets the flag but does not set it back because we have to save the information somewhere in the qdisc if we really want that. Note, both fq_codel and sfq clear this flag in their ->bind_tcf() but this is clearly not sufficient when we don't use any class ID. Fixes: 23624935e0c4 ("net_sched: TCQ_F_CAN_BYPASS generalization") Cc: Eric Dumazet Signed-off-by: Cong Wang Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

cls_matchall: avoid panic when receiving a packet before filter set

2019-06-11T10:19:13Z

[ Upstream commit 25426043ec9e22b90c789407c28e40f32a9d1985 ] When a matchall classifier is added, there is a small time interval in which tp->root is NULL. If we receive a packet in this small time slice a NULL pointer dereference will happen, leading to a kernel panic: # tc qdisc replace dev eth0 ingress # tc filter add dev eth0 parent ffff: matchall action gact drop Unable to handle kernel NULL pointer dereference at virtual address 0000000000000034 Mem abort info: ESR = 0x96000005 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000005 CM = 0, WnR = 0 user pgtable: 4k pages, 39-bit VAs, pgdp = 00000000a623d530 [0000000000000034] pgd=0000000000000000, pud=0000000000000000 Internal error: Oops: 96000005 [#1] SMP Modules linked in: cls_matchall sch_ingress nls_iso8859_1 nls_cp437 vfat fat m25p80 spi_nor mtd xhci_plat_hcd xhci_hcd phy_generic sfp mdio_i2c usbcore i2c_mv64xxx marvell10g mvpp2 usb_common spi_orion mvmdio i2c_core sbsa_gwdt phylink ip_tables x_tables autofs4 Process ksoftirqd/0 (pid: 9, stack limit = 0x0000000009de7d62) CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.1.0-rc6 #21 Hardware name: Marvell 8040 MACCHIATOBin Double-shot (DT) pstate: 40000005 (nZcv daif -PAN -UAO) pc : mall_classify+0x28/0x78 [cls_matchall] lr : tcf_classify+0x78/0x138 sp : ffffff80109db9d0 x29: ffffff80109db9d0 x28: ffffffc426058800 x27: 0000000000000000 x26: ffffffc425b0dd00 x25: 0000000020000000 x24: 0000000000000000 x23: ffffff80109dbac0 x22: 0000000000000001 x21: ffffffc428ab5100 x20: ffffffc425b0dd00 x19: ffffff80109dbac0 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: ffffffbf108ad288 x12: dead000000000200 x11: 00000000f0000000 x10: 0000000000000001 x9 : ffffffbf1089a220 x8 : 0000000000000001 x7 : ffffffbebffaa950 x6 : 0000000000000000 x5 : 000000442d6ba000 x4 : 0000000000000000 x3 : ffffff8008735ad8 x2 : ffffff80109dbac0 x1 : ffffffc425b0dd00 x0 : ffffff8010592078 Call trace: mall_classify+0x28/0x78 [cls_matchall] tcf_classify+0x78/0x138 __netif_receive_skb_core+0x29c/0xa20 __netif_receive_skb_one_core+0x34/0x60 __netif_receive_skb+0x28/0x78 netif_receive_skb_internal+0x2c/0xc0 napi_gro_receive+0x1a0/0x1d8 mvpp2_poll+0x928/0xb18 [mvpp2] net_rx_action+0x108/0x378 __do_softirq+0x128/0x320 run_ksoftirqd+0x44/0x60 smpboot_thread_fn+0x168/0x1b0 kthread+0x12c/0x130 ret_from_fork+0x10/0x1c Code: aa0203f3 aa1e03e0 d503201f f9400684 (b9403480) ---[ end trace fc71e2ef7b8ab5a5 ]--- Kernel panic - not syncing: Fatal exception in interrupt SMP: stopping secondary CPUs Kernel Offset: disabled CPU features: 0x002,00002000 Memory Limit: none Rebooting in 1 seconds.. Fix this by adding a NULL check in mall_classify(). Fixes: ed76f5edccc9 ("net: sched: protect filter_chain list with filter_chain_lock mutex") Signed-off-by: Matteo Croce Acked-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: sched: don't use tc_action->order during action dump

2019-06-04T05:59:42Z

[ Upstream commit 4097e9d250fb17958c1d9b94538386edd3f20144 ] Function tcf_action_dump() relies on tc_action->order field when starting nested nla to send action data to userspace. This approach breaks in several cases: - When multiple filters point to same shared action, tc_action->order field is overwritten each time it is attached to filter. This causes filter dump to output action with incorrect attribute for all filters that have the action in different position (different order) from the last set tc_action->order value. - When action data is displayed using tc action API (RTM_GETACTION), action order is overwritten by tca_action_gd() according to its position in resulting array of nl attributes, which will break filter dump for all filters attached to that shared action that expect it to have different order value. Don't rely on tc_action->order when dumping actions. Set nla according to action position in resulting array of actions instead. Signed-off-by: Vlad Buslov Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sch_cake: Make sure we can write the IP header before changing DSCP bits

2019-04-04T17:55:59Z

There is not actually any guarantee that the IP headers are valid before we access the DSCP bits of the packets. Fix this using the same approach taken in sch_dsmark. Reported-by: Kevin Darbyshire-Bryant Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: David S. Miller

sch_cake: Use tc_skb_protocol() helper for getting packet protocol

2019-04-04T17:55:59Z

We shouldn't be using skb->protocol directly as that will miss cases with hardware-accelerated VLAN tags. Use the helper instead to get the right protocol number. Reported-by: Kevin Darbyshire-Bryant Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: David S. Miller

net/sched: act_sample: fix divide by zero in the traffic path

2019-04-04T17:46:33Z

the control path of 'sample' action does not validate the value of 'rate' provided by the user, but then it uses it as divisor in the traffic path. Validate it in tcf_sample_init(), and return -EINVAL with a proper extack message in case that value is zero, to fix a splat with the script below: # tc f a dev test0 egress matchall action sample rate 0 group 1 index 2 # tc -s a s action sample total acts 1 action order 0: sample rate 1/0 group 1 pipe index 2 ref 1 bind 1 installed 19 sec used 19 sec Action statistics: Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 0 # ping 192.0.2.1 -I test0 -c1 -q divide error: 0000 [#1] SMP PTI CPU: 1 PID: 6192 Comm: ping Not tainted 5.1.0-rc2.diag2+ #591 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 RIP: 0010:tcf_sample_act+0x9e/0x1e0 [act_sample] Code: 6a f1 85 c0 74 0d 80 3d 83 1a 00 00 00 0f 84 9c 00 00 00 4d 85 e4 0f 84 85 00 00 00 e8 9b d7 9c f1 44 8b 8b e0 00 00 00 31 d2 <41> f7 f1 85 d2 75 70 f6 85 83 00 00 00 10 48 8b 45 10 8b 88 08 01 RSP: 0018:ffffae320190ba30 EFLAGS: 00010246 RAX: 00000000b0677d21 RBX: ffff8af1ed9ec000 RCX: 0000000059a9fe49 RDX: 0000000000000000 RSI: 000000000c7e33b7 RDI: ffff8af23daa0af0 RBP: ffff8af1ee11b200 R08: 0000000074fcaf7e R09: 0000000000000000 R10: 0000000000000050 R11: ffffffffb3088680 R12: ffff8af232307f80 R13: 0000000000000003 R14: ffff8af1ed9ec000 R15: 0000000000000000 FS: 00007fe9c6d2f740(0000) GS:ffff8af23da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff6772f000 CR3: 00000000746a2004 CR4: 00000000001606e0 Call Trace: tcf_action_exec+0x7c/0x1c0 tcf_classify+0x57/0x160 __dev_queue_xmit+0x3dc/0xd10 ip_finish_output2+0x257/0x6d0 ip_output+0x75/0x280 ip_send_skb+0x15/0x40 raw_sendmsg+0xae3/0x1410 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x60/0x210 entry_SYSCALL_64_after_hwframe+0x49/0xbe [...] Kernel panic - not syncing: Fatal exception in interrupt Add a TDC selftest to document that 'rate' is now being validated. Reported-by: Matteo Croce Fixes: 5c5670fae430 ("net/sched: Introduce sample tc action") Signed-off-by: Davide Caratti Acked-by: Yotam Gigi Signed-off-by: David S. Miller

net: sched: introduce and use qdisc tree flush/purge helpers

2019-04-01T21:50:13Z

The same code to flush qdisc tree and purge the qdisc queue is duplicated in many places and in most cases it does not respect NOLOCK qdisc: the global backlog len is used and the per CPU values are ignored. This change addresses the above, factoring-out the relevant code and using the helpers introduced by the previous patch to fetch the correct backlog len. Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array") Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller

net: sched: introduce and use qstats read helpers

2019-04-01T21:50:13Z

Classful qdiscs can't access directly the child qdiscs backlog length: if such qdisc is NOLOCK, per CPU values should be accounted instead. Most qdiscs no not respect the above. As a result, qstats fetching for most classful qdisc is currently incorrect: if the child qdisc is NOLOCK, it always reports 0 len backlog. This change introduces a pair of helpers to safely fetch both backlog and qlen and use them in stats class dumping functions, fixing the above issue and cleaning a bit the code. DRR needs also to access the child qdisc queue length, so it needs custom handling. Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array") Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller

net/sched: fix ->get helper of the matchall cls

2019-04-01T21:13:25Z

It returned always NULL, thus it was never possible to get the filter. Example: $ ip link add foo type dummy $ ip link add bar type dummy $ tc qdisc add dev foo clsact $ tc filter add dev foo protocol all pref 1 ingress handle 1234 \ matchall action mirred ingress mirror dev bar Before the patch: $ tc filter get dev foo protocol all pref 1 ingress handle 1234 matchall Error: Specified filter handle not found. We have an error talking to the kernel After: $ tc filter get dev foo protocol all pref 1 ingress handle 1234 matchall filter ingress protocol all pref 1 matchall chain 0 handle 0x4d2 not_in_hw action order 1: mirred (Ingress Mirror to device bar) pipe index 1 ref 1 bind 1 CC: Yotam Gigi CC: Jiri Pirko Fixes: fd62d9f5c575 ("net/sched: matchall: Fix configuration race") Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller