================================================================== BUG: KASAN: use-after-free in smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:664 Read of size 8 at addr ffff8880594b70a8 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.17.0-rc2-syzkaller-00316-g0457e5153e0e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:664 sk_error_report+0x35/0x310 net/core/sock.c:340 tcp_write_err net/ipv4/tcp_timer.c:71 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:276 [inline] tcp_retransmit_timer+0x20c2/0x3320 net/ipv4/tcp_timer.c:512 tcp_write_timer_handler+0x5e6/0xbc0 net/ipv4/tcp_timer.c:622 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] RIP: 0010:acpi_idle_do_entry+0x1c6/0x250 drivers/acpi/processor_idle.c:551 Code: 89 de e8 dd f0 2a f8 84 db 75 ac e8 f4 ec 2a f8 e8 ff 31 31 f8 eb 0c e8 e8 ec 2a f8 0f 00 2d 71 fb c3 00 e8 dc ec 2a f8 fb f4 <9c> 5b 81 e3 00 02 00 00 fa 31 ff 48 89 de e8 57 ef 2a f8 48 85 db RSP: 0018:ffffc90000d57d18 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88801198d700 RSI: ffffffff894d8bb4 RDI: 0000000000000000 RBP: ffff888142bce864 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff817ebdd8 R11: 0000000000000000 R12: 0000000000000001 R13: ffff888142bce800 R14: ffff888142bce864 R15: ffff88814632f804 acpi_idle_enter+0x361/0x500 drivers/acpi/processor_idle.c:687 cpuidle_enter_state+0x1b1/0xc80 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3e8/0x590 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x265/0x340 arch/x86/kernel/smpboot.c:272 secondary_startup_64_no_verify+0xc3/0xcb The buggy address belongs to the page: page:ffffea0001652dc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x100 pfn:0x594b7 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 ffffea0001652d88 0000000000000000 raw: 0000000000000100 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 13503, ts 548929957862, free_ts 561678311677 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab mm/slub.c:1944 [inline] new_slab+0x28a/0x3b0 mm/slub.c:2004 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105 slab_alloc_node mm/slub.c:3196 [inline] slab_alloc mm/slub.c:3238 [inline] kmem_cache_alloc_trace+0x289/0x2c0 mm/slub.c:3255 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:715 [inline] kernfs_iop_get_link fs/kernfs/symlink.c:135 [inline] kernfs_iop_get_link+0x6a/0x720 fs/kernfs/symlink.c:126 pick_link fs/namei.c:1819 [inline] step_into+0x17be/0x1d80 fs/namei.c:1876 open_last_lookups fs/namei.c:3423 [inline] path_openat+0x4a4/0x2940 fs/namei.c:3606 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1214 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3404 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x6d/0x160 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446 kasan_slab_alloc include/linux/kasan.h:260 [inline] slab_post_alloc_hook mm/slab.h:732 [inline] slab_alloc_node mm/slub.c:3230 [inline] slab_alloc mm/slub.c:3238 [inline] kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3243 __d_alloc+0x2a/0x950 fs/dcache.c:1769 d_alloc_anon fs/dcache.c:1867 [inline] d_alloc_cursor+0x3b/0xd0 fs/dcache.c:1873 dcache_dir_open+0x33/0x90 fs/libfs.c:82 do_dentry_open+0x4b9/0x1240 fs/open.c:824 do_open fs/namei.c:3476 [inline] path_openat+0x1c9e/0x2940 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1214 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff8880594b6f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880594b7000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880594b7080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880594b7100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880594b7180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== ---------------- Code disassembly (best guess): 0: 89 de mov %ebx,%esi 2: e8 dd f0 2a f8 callq 0xf82af0e4 7: 84 db test %bl,%bl 9: 75 ac jne 0xffffffb7 b: e8 f4 ec 2a f8 callq 0xf82aed04 10: e8 ff 31 31 f8 callq 0xf8313214 15: eb 0c jmp 0x23 17: e8 e8 ec 2a f8 callq 0xf82aed04 1c: 0f 00 2d 71 fb c3 00 verw 0xc3fb71(%rip) # 0xc3fb94 23: e8 dc ec 2a f8 callq 0xf82aed04 28: fb sti 29: f4 hlt * 2a: 9c pushfq <-- trapping instruction 2b: 5b pop %rbx 2c: 81 e3 00 02 00 00 and $0x200,%ebx 32: fa cli 33: 31 ff xor %edi,%edi 35: 48 89 de mov %rbx,%rsi 38: e8 57 ef 2a f8 callq 0xf82aef94 3d: 48 85 db test %rbx,%rbx