Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-rc3-syzkaller-00062-gc061cf420ded #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:_compound_head include/linux/page-flags.h:242 [inline] RIP: 0010:get_page include/linux/mm.h:1460 [inline] RIP: 0010:__skb_frag_ref include/linux/skbuff_ref.h:20 [inline] RIP: 0010:skb_frag_ref include/linux/skbuff_ref.h:32 [inline] RIP: 0010:pskb_expand_head+0x8ac/0x1170 net/core/skbuff.c:2300 Code: 41 83 e7 01 4c 89 fe e8 d2 76 a1 f8 4d 85 ff 0f 85 c3 02 00 00 e8 54 74 a1 f8 e8 4f 74 a1 f8 48 8d 7d 08 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 0f 85 28 07 00 00 4c 8b 7d 08 31 ff 4c 89 fb 83 e3 RSP: 0018:ffffc90000007748 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff88802ad99e00 RCX: ffffffff88f7da8e RDX: ffffffff8da977c0 RSI: ffffffff88f7daa1 RDI: 0000000000000008 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000022 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000030 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88802b400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f7456994 CR3: 000000006297a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __skb_unclone_keeptruesize+0x91/0x280 net/core/skbuff.c:2375 skb_unclone_keeptruesize include/linux/skbuff.h:1998 [inline] __tcp_retransmit_skb.part.0+0xc58/0x2680 net/ipv4/tcp_output.c:3376 __tcp_retransmit_skb net/ipv4/tcp_output.c:3330 [inline] tcp_send_loss_probe+0x454/0xb00 net/ipv4/tcp_output.c:2982 tcp_write_timer_handler net/ipv4/tcp_timer.c:710 [inline] tcp_write_timer_handler+0x59d/0xa70 net/ipv4/tcp_timer.c:688 tcp_write_timer+0x157/0x2f0 net/ipv4/tcp_timer.c:735 call_timer_fn+0x1a0/0x610 kernel/time/timer.c:1793 expire_timers kernel/time/timer.c:1844 [inline] __run_timers+0x6e8/0x930 kernel/time/timer.c:2418 __run_timer_base kernel/time/timer.c:2430 [inline] __run_timer_base kernel/time/timer.c:2422 [inline] timer_expire_remote+0x102/0x170 kernel/time/timer.c:2181 tmigr_handle_remote_cpu kernel/time/timer_migration.c:930 [inline] tmigr_handle_remote_up kernel/time/timer_migration.c:1021 [inline] __walk_groups kernel/time/timer_migration.c:533 [inline] tmigr_handle_remote+0x78e/0xdd0 kernel/time/timer_migration.c:1080 run_timer_softirq+0x35/0x40 kernel/time/timer.c:2453 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:default_idle+0xf/0x20 arch/x86/kernel/process.c:743 Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 03 7e 2c 00 fb f4 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 RSP: 0018:ffffffff8da07e20 EFLAGS: 00000202 RAX: 000000000015d537 RBX: 0000000000000000 RCX: ffffffff8b1a0819 RDX: 0000000000000000 RSI: ffffffff8b4cd180 RDI: ffffffff8bb16d40 RBP: fffffbfff1b52ef8 R08: 0000000000000001 R09: ffffed1005686fed R10: ffff88802b437f6b R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8da977c0 R14: ffffffff901ce110 R15: 0000000000000000 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x329/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:747 start_kernel+0x3e4/0x4d0 init/main.c:1102 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:_compound_head include/linux/page-flags.h:242 [inline] RIP: 0010:get_page include/linux/mm.h:1460 [inline] RIP: 0010:__skb_frag_ref include/linux/skbuff_ref.h:20 [inline] RIP: 0010:skb_frag_ref include/linux/skbuff_ref.h:32 [inline] RIP: 0010:pskb_expand_head+0x8ac/0x1170 net/core/skbuff.c:2300 Code: 41 83 e7 01 4c 89 fe e8 d2 76 a1 f8 4d 85 ff 0f 85 c3 02 00 00 e8 54 74 a1 f8 e8 4f 74 a1 f8 48 8d 7d 08 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 0f 85 28 07 00 00 4c 8b 7d 08 31 ff 4c 89 fb 83 e3 RSP: 0018:ffffc90000007748 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff88802ad99e00 RCX: ffffffff88f7da8e RDX: ffffffff8da977c0 RSI: ffffffff88f7daa1 RDI: 0000000000000008 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000022 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000030 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88802b400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f7456994 CR3: 000000006297a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 41 83 e7 01 and $0x1,%r15d 4: 4c 89 fe mov %r15,%rsi 7: e8 d2 76 a1 f8 call 0xf8a176de c: 4d 85 ff test %r15,%r15 f: 0f 85 c3 02 00 00 jne 0x2d8 15: e8 54 74 a1 f8 call 0xf8a1746e 1a: e8 4f 74 a1 f8 call 0xf8a1746e 1f: 48 8d 7d 08 lea 0x8(%rbp),%rdi 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction 2f: 0f 85 28 07 00 00 jne 0x75d 35: 4c 8b 7d 08 mov 0x8(%rbp),%r15 39: 31 ff xor %edi,%edi 3b: 4c 89 fb mov %r15,%rbx 3e: 83 .byte 0x83 3f: e3 .byte 0xe3