From dd08ab952b6080a1d417823ba0ae18ce9b4e23f9 Mon Sep 17 00:00:00 2001 From: Yue Haibing Date: Fri, 24 May 2024 16:51:08 +0800 Subject: [PATCH] net/sched: Add xmit_recursion level in sch_direct_xmit() packet from PF_PACKET socket ontop of an IPv6-backed ipvlan device will hit WARN_ON_ONCE() in sk_mc_loop() through sch_direct_xmit() path while ipvlan device has qdisc queue. WARNING: CPU: 2 PID: 0 at net/core/sock.c:775 sk_mc_loop+0x2d/0x70 Modules linked in: sch_netem ipvlan rfkill cirrus drm_shmem_helper sg drm_kms_helper CPU: 2 PID: 0 Comm: swapper/2 Kdump: loaded Not tainted 6.9.0+ #279 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:sk_mc_loop+0x2d/0x70 Code: fa 0f 1f 44 00 00 65 0f b7 15 f7 96 a3 4f 31 c0 66 85 d2 75 26 48 85 ff 74 1c RSP: 0018:ffffa9584015cd78 EFLAGS: 00010212 RAX: 0000000000000011 RBX: ffff91e585793e00 RCX: 0000000002c6a001 RDX: 0000000000000000 RSI: 0000000000000040 RDI: ffff91e589c0f000 RBP: ffff91e5855bd100 R08: 0000000000000000 R09: 3d00545216f43d00 R10: ffff91e584fdcc50 R11: 00000060dd8616f4 R12: ffff91e58132d000 R13: ffff91e584fdcc68 R14: ffff91e5869ce800 R15: ffff91e589c0f000 FS: 0000000000000000(0000) GS:ffff91e898100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f788f7c44c0 CR3: 0000000008e1a000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? __warn+0x83/0x130 ? sk_mc_loop+0x2d/0x70 ? report_bug+0x18e/0x1a0 ? handle_bug+0x3c/0x70 ? exc_invalid_op+0x18/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? sk_mc_loop+0x2d/0x70 ip6_finish_output2+0x31e/0x590 ? nf_hook_slow+0x43/0xf0 ip6_finish_output+0x1f8/0x320 ? __pfx_ip6_finish_output+0x10/0x10 ipvlan_xmit_mode_l3+0x22a/0x2a0 [ipvlan] ipvlan_start_xmit+0x17/0x50 [ipvlan] dev_hard_start_xmit+0x8c/0x1d0 sch_direct_xmit+0xa2/0x390 __qdisc_run+0x66/0xd0 net_tx_action+0x1ca/0x270 handle_softirqs+0xd6/0x2b0 __irq_exit_rcu+0x9b/0xc0 sysvec_apic_timer_interrupt+0x75/0x90 Fixes: f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack") Signed-off-by: Yue Haibing --- include/linux/netdevice.h | 17 +++++++++++++++++ net/core/dev.h | 17 ----------------- net/sched/sch_generic.c | 8 +++++--- 3 files changed, 22 insertions(+), 20 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index d20c6c99eb887c..7c0c9e9b045ea3 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3261,6 +3261,23 @@ static inline int dev_recursion_level(void) return this_cpu_read(softnet_data.xmit.recursion); } +#define XMIT_RECURSION_LIMIT 8 +static inline bool dev_xmit_recursion(void) +{ + return unlikely(__this_cpu_read(softnet_data.xmit.recursion) > + XMIT_RECURSION_LIMIT); +} + +static inline void dev_xmit_recursion_inc(void) +{ + __this_cpu_inc(softnet_data.xmit.recursion); +} + +static inline void dev_xmit_recursion_dec(void) +{ + __this_cpu_dec(softnet_data.xmit.recursion); +} + void __netif_schedule(struct Qdisc *q); void netif_schedule_queue(struct netdev_queue *txq); diff --git a/net/core/dev.h b/net/core/dev.h index b7b518bc2be55a..49345ad7350bd9 100644 --- a/net/core/dev.h +++ b/net/core/dev.h @@ -149,21 +149,4 @@ static inline void xdp_do_check_flushed(struct napi_struct *napi) { } struct napi_struct *napi_by_id(unsigned int napi_id); void kick_defer_list_purge(struct softnet_data *sd, unsigned int cpu); -#define XMIT_RECURSION_LIMIT 8 -static inline bool dev_xmit_recursion(void) -{ - return unlikely(__this_cpu_read(softnet_data.xmit.recursion) > - XMIT_RECURSION_LIMIT); -} - -static inline void dev_xmit_recursion_inc(void) -{ - __this_cpu_inc(softnet_data.xmit.recursion); -} - -static inline void dev_xmit_recursion_dec(void) -{ - __this_cpu_dec(softnet_data.xmit.recursion); -} - #endif diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 2a637a17061b91..74d9b43b776732 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -339,11 +339,13 @@ bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, if (likely(skb)) { HARD_TX_LOCK(dev, txq, smp_processor_id()); - if (!netif_xmit_frozen_or_stopped(txq)) + if (!netif_xmit_frozen_or_stopped(txq)) { + dev_xmit_recursion_inc(); skb = dev_hard_start_xmit(skb, dev, txq, &ret); - else + dev_xmit_recursion_dec(); + } else { qdisc_maybe_clear_missed(q, txq); - + } HARD_TX_UNLOCK(dev, txq); } else { if (root_lock)