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: 1 UID: 0 PID: 6693 Comm: syz.4.265 Not tainted 6.13.0-rc5-syzkaller-00012-g0bc21e701a6f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:_compound_head include/linux/page-flags.h:242 [inline] RIP: 0010:get_page include/linux/mm.h:1461 [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+0x97d/0x1240 net/core/skbuff.c:2300 Code: 83 e6 01 4c 89 f6 e8 32 40 96 f8 4d 85 f6 0f 85 7f 03 00 00 e8 b4 3d 96 f8 e8 af 3d 96 f8 49 8d 7c 24 08 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 da 06 00 00 4d 8b 74 24 08 31 ff 4d 89 f7 41 RSP: 0018:ffffc90000a188a8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000030 RCX: ffffffff8903d85e RDX: ffff88807a092440 RSI: ffffffff8903d871 RDI: 0000000000000008 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000140 FS: 00007f2250d6a6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020024000 CR3: 00000000786ba000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __skb_unclone_keeptruesize+0x91/0x2c0 net/core/skbuff.c:2375 skb_unclone_keeptruesize include/linux/skbuff.h:1998 [inline] __tcp_retransmit_skb.part.0+0xeff/0x2690 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] run_timer_base+0x114/0x190 kernel/time/timer.c:2439 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2449 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:pagefault_disabled include/linux/uaccess.h:284 [inline] RIP: 0010:__might_fault+0x48/0x190 mm/memory.c:6746 Code: ff df 65 4c 8b 25 28 4e 21 7e 49 8d bc 24 84 17 00 00 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 <84> d2 0f 85 11 01 00 00 45 8b a4 24 84 17 00 00 31 ff 44 89 e6 e8 RSP: 0018:ffffc9001076fc20 EFLAGS: 00000202 RAX: 0000000000000007 RBX: ffffffff8bd19d40 RCX: ffffc9000e199000 RDX: 0000000000000000 RSI: ffffffff81e28ac6 RDI: ffff88807a093bc4 RBP: 00000000000000c0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88807a092440 R13: ffffc9001076fcb8 R14: 0000000020024d50 R15: 0000000020019680 _inline_copy_to_user include/linux/uaccess.h:192 [inline] _copy_to_user+0x2d/0xd0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:225 [inline] msr_read+0x14f/0x250 arch/x86/kernel/msr.c:69 vfs_read+0x1df/0xbe0 fs/read_write.c:563 ksys_read+0x12b/0x250 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f224ff85d29 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2250d6a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f2250175fa0 RCX: 00007f224ff85d29 RDX: 0000000000018ff8 RSI: 0000000020019680 RDI: 0000000000000003 RBP: 00007f2250001b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2250175fa0 R15: 00007ffd83f14f38 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:1461 [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+0x97d/0x1240 net/core/skbuff.c:2300 Code: 83 e6 01 4c 89 f6 e8 32 40 96 f8 4d 85 f6 0f 85 7f 03 00 00 e8 b4 3d 96 f8 e8 af 3d 96 f8 49 8d 7c 24 08 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 da 06 00 00 4d 8b 74 24 08 31 ff 4d 89 f7 41 RSP: 0018:ffffc90000a188a8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000030 RCX: ffffffff8903d85e RDX: ffff88807a092440 RSI: ffffffff8903d871 RDI: 0000000000000008 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000140 FS: 00007f2250d6a6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020024000 CR3: 00000000786ba000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 83 e6 01 and $0x1,%esi 3: 4c 89 f6 mov %r14,%rsi 6: e8 32 40 96 f8 call 0xf896403d b: 4d 85 f6 test %r14,%r14 e: 0f 85 7f 03 00 00 jne 0x393 14: e8 b4 3d 96 f8 call 0xf8963dcd 19: e8 af 3d 96 f8 call 0xf8963dcd 1e: 49 8d 7c 24 08 lea 0x8(%r12),%rdi 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 0f 85 da 06 00 00 jne 0x70f 35: 4d 8b 74 24 08 mov 0x8(%r12),%r14 3a: 31 ff xor %edi,%edi 3c: 4d 89 f7 mov %r14,%r15 3f: 41 rex.B