bisecting fixing commit since d567f5db412ed52de0b3b3efca4a451263de6108 building syzkaller on 8b9ca619df135211a89cc19719f2705d0016045d testing commit d567f5db412ed52de0b3b3efca4a451263de6108 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 834c7d75d6dc97fec759c900783439560674fbcd8b5975682e451e9e7047e1ca all runs: crashed: KASAN: use-after-free Read in ath9k_hif_usb_reg_in_cb testing current HEAD 42226c989789d8da4af1de0c31070c96726d990c testing commit 42226c989789d8da4af1de0c31070c96726d990c compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: af932172f1f821c940f891a2bff91edc8f41c271e8979f3a4c019a263c635692 all runs: crashed: KASAN: use-after-free Read in ath9k_hif_usb_reg_in_cb revisions tested: 2, total time: 19m39.701449114s (build: 12m17.441734475s, test: 6m51.899492418s) the crash still happens on HEAD commit msg: Linux 5.18-rc7 crash: KASAN: use-after-free Read in ath9k_hif_usb_reg_in_cb usb 1-1: ath: unknown panic pattern! ================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:147 [inline] BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:1234 [inline] BUG: KASAN: use-after-free in kfree_skb_reason+0x28/0xb0 net/core/skbuff.c:772 Read of size 4 at addr ffff8880235bed54 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.18.0-rc7-syzkaller #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+0x57/0x7d lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] refcount_read include/linux/refcount.h:147 [inline] skb_unref include/linux/skbuff.h:1234 [inline] kfree_skb_reason+0x28/0xb0 net/core/skbuff.c:772 kfree_skb include/linux/skbuff.h:1250 [inline] ath9k_hif_usb_reg_in_cb+0x470/0x600 drivers/net/wireless/ath/ath9k/hif_usb.c:771 __usb_hcd_giveback_urb+0x238/0x3f0 drivers/usb/core/hcd.c:1670 dummy_timer+0xeb8/0x2eb0 drivers/usb/gadget/udc/dummy_hcd.c:1988 call_timer_fn+0x163/0x4a0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x530/0x8e0 kernel/time/timer.c:1737 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0x9c/0x190 kernel/time/timer.c:1750 __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:645 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+0x15e/0x1c0 drivers/acpi/processor_idle.c:551 Code: 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 6a 48 8b 45 00 a8 08 75 c9 e8 5d d2 e1 f8 eb 07 0f 00 2d 54 ff bc 00 fb f4 <9c> 58 fa f6 c4 02 74 b1 5d e9 34 d1 e1 f8 48 89 ef 5d e9 ab f9 ff RSP: 0018:ffffc90000177d38 EFLAGS: 00000202 RAX: 0000000000053d25 RBX: ffff88801533d065 RCX: 1ffffffff194d489 RDX: 0000000000000000 RSI: ffffffff88eb90a0 RDI: ffffffff8942c2a0 RBP: ffff88800fe71d40 R08: 0000000000000001 R09: 0000000000000001 R10: ffffed1001fce3a8 R11: 0000000000000001 R12: 0000000000000001 R13: ffff88801533d064 R14: ffffffff8b7396c0 R15: ffff8881474b4804 acpi_idle_enter+0x2c0/0x4b0 drivers/acpi/processor_idle.c:686 cpuidle_enter_state+0x152/0xb40 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x45/0xa0 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3e8/0x590 kernel/sched/idle.c:303 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:400 start_secondary+0x224/0x2c0 arch/x86/kernel/smpboot.c:266 secondary_startup_64_no_verify+0xc3/0xcb Allocated by task 3603: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:469 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3267 __alloc_skb+0x151/0x270 net/core/skbuff.c:414 alloc_skb include/linux/skbuff.h:1300 [inline] ath9k_hif_usb_alloc_reg_in_urbs drivers/net/wireless/ath/ath9k/hif_usb.c:964 [inline] ath9k_hif_usb_alloc_urbs+0x877/0xef0 drivers/net/wireless/ath/ath9k/hif_usb.c:1023 ath9k_hif_usb_dev_init drivers/net/wireless/ath/ath9k/hif_usb.c:1109 [inline] ath9k_hif_usb_firmware_cb+0x121/0x4d0 drivers/net/wireless/ath/ath9k/hif_usb.c:1242 request_firmware_work_func+0x126/0x230 drivers/base/firmware_loader/main.c:1039 process_one_work+0x865/0x13d0 kernel/workqueue.c:2289 worker_thread+0x598/0xec0 kernel/workqueue.c:2436 kthread+0x299/0x340 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Freed by task 0: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kmem_cache_free+0xdd/0x5a0 mm/slub.c:3527 ath9k_hif_usb_reg_in_cb+0x178/0x600 drivers/net/wireless/ath/ath9k/hif_usb.c:740 __usb_hcd_giveback_urb+0x238/0x3f0 drivers/usb/core/hcd.c:1670 dummy_timer+0xeb8/0x2eb0 drivers/usb/gadget/udc/dummy_hcd.c:1988 call_timer_fn+0x163/0x4a0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x530/0x8e0 kernel/time/timer.c:1737 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0x9c/0x190 kernel/time/timer.c:1750 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 The buggy address belongs to the object at ffff8880235bec80 which belongs to the cache skbuff_head_cache of size 224 The buggy address is located 212 bytes inside of 224-byte region [ffff8880235bec80, ffff8880235bed60) The buggy address belongs to the physical page: page:ffffea00008d6f80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x235be flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea00005ef9c0 dead000000000002 ffff888140aee500 raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 2961, tgid 2961 (udevd), ts 12079950250, free_ts 12055431560 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0x178d/0x3dc0 mm/page_alloc.c:4182 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x8e1/0xf20 mm/slub.c:3005 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092 slab_alloc_node mm/slub.c:3183 [inline] kmem_cache_alloc_node+0x122/0x3f0 mm/slub.c:3267 __alloc_skb+0x151/0x270 net/core/skbuff.c:414 alloc_skb include/linux/skbuff.h:1300 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1191 [inline] netlink_sendmsg+0x7f3/0xc20 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xab/0xe0 net/socket.c:725 ____sys_sendmsg+0x5b9/0x7a0 net/socket.c:2413 ___sys_sendmsg+0xd3/0x150 net/socket.c:2467 __sys_sendmsg+0xb2/0x140 net/socket.c:2496 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 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:1356 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3328 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2523 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x6a/0x170 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:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x200/0x350 mm/slub.c:4410 kmalloc include/linux/slab.h:586 [inline] tomoyo_realpath_from_path+0xb0/0x6a0 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x21c/0x2c0 security/tomoyo/file.c:771 security_file_open+0x34/0x80 security/security.c:1651 do_dentry_open+0x300/0xfd0 fs/open.c:811 do_open fs/namei.c:3476 [inline] path_openat+0x9cf/0x2360 fs/namei.c:3609 do_filp_open+0x199/0x3d0 fs/namei.c:3636 do_sys_openat2+0x11e/0x3f0 fs/open.c:1213 do_sys_open fs/open.c:1229 [inline] __do_sys_openat fs/open.c:1245 [inline] __se_sys_openat fs/open.c:1240 [inline] __x64_sys_openat+0x11b/0x1d0 fs/open.c:1240 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff8880235bec00: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ffff8880235bec80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880235bed00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8880235bed80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff8880235bee00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 00 add %al,(%rax) 4: 00 fc add %bh,%ah 6: ff (bad) 7: df 48 c1 fisttps -0x3f(%rax) a: ea (bad) b: 03 80 3c 02 00 75 add 0x7500023c(%rax),%eax 11: 6a 48 pushq $0x48 13: 8b 45 00 mov 0x0(%rbp),%eax 16: a8 08 test $0x8,%al 18: 75 c9 jne 0xffffffe3 1a: e8 5d d2 e1 f8 callq 0xf8e1d27c 1f: eb 07 jmp 0x28 21: 0f 00 2d 54 ff bc 00 verw 0xbcff54(%rip) # 0xbcff7c 28: fb sti 29: f4 hlt * 2a: 9c pushfq <-- trapping instruction 2b: 58 pop %rax 2c: fa cli 2d: f6 c4 02 test $0x2,%ah 30: 74 b1 je 0xffffffe3 32: 5d pop %rbp 33: e9 34 d1 e1 f8 jmpq 0xf8e1d16c 38: 48 89 ef mov %rbp,%rdi 3b: 5d pop %rbp 3c: e9 .byte 0xe9 3d: ab stos %eax,%es:(%rdi) 3e: f9 stc 3f: ff .byte 0xff