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+0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US X-Stat-Signature: rkwnbh6ximiztuph7sskz7d8jddg6r9u Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=q0gWLweE; spf=pass (imf15.hostedemail.com: domain of qiang.zhang1211@gmail.com designates 209.85.216.49 as permitted sender) smtp.mailfrom=qiang.zhang1211@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 97EAAD000081 X-HE-Tag: 1634532220-415461 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 2021/10/14 =E4=B8=8A=E5=8D=8810:38, Hao Sun wrote: > Hillf Danton =E4=BA=8E2021=E5=B9=B49=E6=9C=887=E6=97= =A5=E5=91=A8=E4=BA=8C =E4=B8=8B=E5=8D=883:44=E5=86=99=E9=81=93=EF=BC=9A >> On Tue, 7 Sep 2021 09:22:03 +0800 Hao Sun wrote: >>> When using Healer to fuzz the latest Linux kernel, the following cras= h >>> was triggered. >>> >>> HEAD commit: 27151f177827 Merge tag 'perf-tools-for-v5.15-2021-09-04' >>> git tree: upstream >>> console output: >>> https://drive.google.com/file/d/1M5oyA_IcWSDB2XpnoX8SDmKJA3JhKltz/vie= w?usp=3Dsharing >>> kernel config: https://drive.google.com/file/d/1ZMVJ2vNe0EiIEeWNVyrGb= 7hBdOG5Uj3e/view?usp=3Dsharing >>> C reproducer: https://drive.google.com/file/d/1AtDNXl8XEBfglKXsKsAH2N= uXBcrp8Zp9/view?usp=3Dsharing >>> Syzlang reproducer: >>> https://drive.google.com/file/d/1R_XD_cyMNS0Q_SGSqomRy_LIClOrd-gI/vie= w?usp=3Dsharing >>> >>> If you fix this issue, please add the following tag to the commit: >>> Reported-by: Hao Sun >> Thanks for reporting it. >> >>> ODEBUG: object ffffc9000073cda0 is NOT on stack ffffc90005f34000, but= annotated. >>> ------------[ cut here ]------------ >>> WARNING: CPU: 2 PID: 27648 at lib/debugobjects.c:548 >>> debug_object_is_on_stack lib/debugobjects.c:545 [inline] >>> WARNING: CPU: 2 PID: 27648 at lib/debugobjects.c:548 >>> __debug_object_init+0x224/0x520 lib/debugobjects.c:607 >>> Modules linked in: >>> CPU: 2 PID: 27648 Comm: syz-executor Not tainted 5.14.0+ #13 >>> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS >>> rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 >>> RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:545 [inline] >>> RIP: 0010:__debug_object_init+0x224/0x520 lib/debugobjects.c:607 >>> Code: 84 ca fe ff ff 83 c0 01 4c 89 f6 48 c7 c7 f8 b0 3c 85 89 05 7e >>> c2 56 06 65 48 8b 04 25 40 70 01 00 48 8b 50 20 e8 05 9b f5 01 <0f> 0= b >>> e9 9e fe ff ff 89 05 87 4d e3 03 e9 c4 fe ff ff 48 c7 c7 e0 >>> RSP: 0018:ffffc9000073ccf0 EFLAGS: 00010282 >>> RAX: 0000000000000050 RBX: ffff88810cf2f398 RCX: 0000000000000100 >>> RDX: 0000000000000000 RSI: ffffffff812cf85c RDI: 00000000ffffffff >>> RBP: ffffffff88868538 R08: 0000000000000000 R09: 0000000000000001 >>> R10: ffffc9000073cc80 R11: 0000000000000005 R12: 0000000000000203 >>> R13: 0000000000054450 R14: ffffc9000073cda0 R15: ffff88807dd264f0 >>> FS: 0000000002ad0940(0000) GS:ffff88807dd00000(0000) knlGS:000000000= 0000000 >>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>> CR2: 00000000005061ec CR3: 0000000100da5000 CR4: 0000000000750ee0 >>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >>> PKRU: 55555554 >>> Call Trace: >>> >>> __init_work+0x3f/0x50 kernel/workqueue.c:519 >>> synchronize_rcu_expedited+0x26a/0x460 kernel/rcu/tree_exp.h:847 >> Given wait_event() in synchronize_rcu_expedited(), it is no good to co= me >> in a rcu context. >> >>> bdi_remove_from_list mm/backing-dev.c:938 [inline] >>> bdi_unregister+0x97/0x270 mm/backing-dev.c:946 >>> release_bdi+0x4a/0x70 mm/backing-dev.c:968 >>> kref_put include/linux/kref.h:65 [inline] >>> bdi_put+0x47/0x70 mm/backing-dev.c:976 >>> bdev_free_inode+0x59/0xc0 fs/block_dev.c:819 >>> i_callback+0x24/0x50 fs/inode.c:224 >>> rcu_do_batch kernel/rcu/tree.c:2508 [inline] >>> rcu_core+0x2d6/0x9f0 kernel/rcu/tree.c:2743 >>> __do_softirq+0xe9/0x561 kernel/softirq.c:558 >>> invoke_softirq kernel/softirq.c:432 [inline] >>> __irq_exit_rcu kernel/softirq.c:636 [inline] >>> irq_exit_rcu+0xe2/0x100 kernel/softirq.c:648 >>> sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1= 097 >>> >>> asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idte= ntry.h:638 >>> RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x60 kernel/kcov.c:197 >>> Code: 65 48 8b 14 25 40 70 01 00 81 e1 00 01 00 00 a9 00 01 ff 00 74 >>> 0e 85 c9 74 35 8b 82 34 15 00 00 85 c0 74 2b 8b 82 10 15 00 00 <83> f= 8 >>> 02 75 20 48 8b 8a 18 15 00 00 8b 92 14 15 00 00 48 8b 01 48 >>> RSP: 0018:ffffc90005f37b78 EFLAGS: 00000246 >>> RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000000000 >>> RDX: ffff888109448000 RSI: ffffffff8212a28c RDI: ffffc90005f37d30 >>> RBP: 0000000000000006 R08: 0000000000000d40 R09: ffff8880165fc5e0 >>> R10: ffffc90005f37cd0 R11: 0000000000000003 R12: 0000000000000375 >>> R13: ffff888107597b40 R14: ffffc90005f37d30 R15: ffff8880174b0ea0 >>> tomoyo_domain_quota_is_ok+0xac/0x150 security/tomoyo/util.c:1092 >>> tomoyo_supervisor+0x228/0x7f0 security/tomoyo/common.c:2089 >>> tomoyo_audit_path_log security/tomoyo/file.c:168 [inline] >>> tomoyo_path_permission+0xa0/0xf0 security/tomoyo/file.c:587 >>> tomoyo_path_perm+0x22f/0x2d0 security/tomoyo/file.c:838 >>> tomoyo_path_symlink+0x43/0x70 security/tomoyo/tomoyo.c:199 >>> security_path_symlink+0x48/0x80 security/security.c:1164 >>> do_symlinkat+0x75/0x120 fs/namei.c:4274 >>> __do_sys_symlink fs/namei.c:4301 [inline] >>> __se_sys_symlink fs/namei.c:4299 [inline] >>> __x64_sys_symlink+0x3a/0x40 fs/namei.c:4299 >>> do_syscall_x64 arch/x86/entry/common.c:50 [inline] >>> do_syscall_64+0x34/0xb0 arch/x86/entry/common.c:80 >>> entry_SYSCALL_64_after_hwframe+0x44/0xae >>> RIP: 0033:0x46a597 >>> Code: 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 >>> 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 58 00 00 00 0f 05 <48> 3= d >>> 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 >>> RSP: 002b:00007ffd09085778 EFLAGS: 00000206 ORIG_RAX: 000000000000005= 8 >>> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000046a597 >>> RDX: 0000000000000000 RSI: 00000000004e40f9 RDI: 00007ffd09085810 >>> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000014 >>> R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 >>> R13: 0000000000000000 R14: 00007ffd09085810 R15: 00007ffd090857cc >>> ---------------- >>> Code disassembly (best guess): >>> 0: 65 48 8b 14 25 40 70 mov %gs:0x17040,%rdx >>> 7: 01 00 >>> 9: 81 e1 00 01 00 00 and $0x100,%ecx >>> f: a9 00 01 ff 00 test $0xff0100,%eax >>> 14: 74 0e je 0x24 >>> 16: 85 c9 test %ecx,%ecx >>> 18: 74 35 je 0x4f >>> 1a: 8b 82 34 15 00 00 mov 0x1534(%rdx),%eax >>> 20: 85 c0 test %eax,%eax >>> 22: 74 2b je 0x4f >>> 24: 8b 82 10 15 00 00 mov 0x1510(%rdx),%eax >>> * 2a: 83 f8 02 cmp $0x2,%eax <-- trapping instruction >>> 2d: 75 20 jne 0x4f >>> 2f: 48 8b 8a 18 15 00 00 mov 0x1518(%rdx),%rcx >>> 36: 8b 92 14 15 00 00 mov 0x1514(%rdx),%edx >>> 3c: 48 8b 01 mov (%rcx),%rax >>> 3f: 48 rex.W% >>> >> Move releasing of bdi to workqueue work to make it safe to sync rcu. >> >> Only for thoughts now. >> >> +++ x/mm/backing-dev.c >> @@ -959,10 +959,11 @@ void bdi_unregister(struct backing_dev_i >> } >> } >> >> -static void release_bdi(struct kref *ref) >> +static void bdi_release_workfn(struct work_struct *work) >> { >> - struct backing_dev_info *bdi =3D >> - container_of(ref, struct backing_dev_info, ref= cnt); >> + struct backing_dev_info *bdi; >> + >> + bdi =3D container_of(work, struct backing_dev_info, release_wo= rk); >> >> if (test_bit(WB_registered, &bdi->wb.state)) >> bdi_unregister(bdi); >> @@ -971,6 +972,16 @@ static void release_bdi(struct kref *ref >> kfree(bdi); >> } >> >> +static void release_bdi(struct kref *ref) >> +{ >> + struct backing_dev_info *bdi; >> + >> + bdi =3D container_of(ref, struct backing_dev_info, refcnt); >> + >> + INIT_WORK(&bdi->release_work, bdi_release_workfn); >> + queue_work(system_unbound_wq, &bdi->release_work); >> +} >> + >> void bdi_put(struct backing_dev_info *bdi) >> { >> kref_put(&bdi->refcnt, release_bdi); > Hi, > > This issue can still be triggered repeatedly on the latest Linux kernel= . > > HEAD commit: 64570fbc14f8 Linux 5.15-rc5 > git tree: upstream > kernel config: https://drive.google.com/file/d/1em3xgUIMNN_-LUUdySzwN-U= DPc3qiiKD/view?usp=3Dsharing > > ODEBUG: object ffffc90000007bc0 is NOT on stack ffffffff8b600000, but a= nnotated. > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:548 > debug_object_is_on_stack lib/debugobjects.c:542 [inline] > WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:548 > __debug_object_init.cold+0x21d/0x29a lib/debugobjects.c:607 > Modules linked in: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.0-rc5 #3 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > 1.13.0-1ubuntu1.1 04/01/2014 > RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:548 [inline] > RIP: 0010:__debug_object_init.cold+0x21d/0x29a lib/debugobjects.c:607 > Code: 00 48 8d 7b 20 48 89 fa 48 c1 ea 03 80 3c 02 00 74 05 e8 2a 7d > be f8 48 8b 53 20 4c 89 e6 48 c7 c7 80 3b e4 89 e8 22 42 f2 ff <0f> 0b > e9 cf bc e6 fa 4c 89 e0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 > RSP: 0018:ffffc900000079f0 EFLAGS: 00010282 > RAX: 0000000000000050 RBX: ffffffff8b6bc640 RCX: 0000000000000000 > RDX: 0000000000000000 RSI: ffffffff8b6bc640 RDI: fffff52000000f30 > RBP: ffffffff8b6bc640 R08: 0000000000000050 R09: 0000000000000000 > R10: 0000000000000005 R11: ffffed100c7c57f8 R12: ffffc90000007bc0 > R13: 1ffff92000000f4c R14: ffffffff90472c30 R15: ffffffff90472c38 > FS: 0000000000000000(0000) GS:ffff888063e00000(0000) knlGS:00000000000= 00000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000555556100c48 CR3: 00000000279c8000 CR4: 0000000000350ef0 > Call Trace: > > __init_work+0x2d/0x50 kernel/workqueue.c:519 > synchronize_rcu_expedited+0x3af/0x650 kernel/rcu/tree_exp.h:847 > bdi_remove_from_list mm/backing-dev.c:938 [inline] > bdi_unregister+0x17f/0x5c0 mm/backing-dev.c:946 > release_bdi+0xa1/0xc0 mm/backing-dev.c:968 > kref_put include/linux/kref.h:65 [inline] > bdi_put+0x72/0xa0 mm/backing-dev.c:976 > bdev_free_inode+0x11e/0x220 block/bdev.c:408 > i_callback+0x3f/0x70 fs/inode.c:226 > rcu_do_batch kernel/rcu/tree.c:2508 [inline] > rcu_core+0x76d/0x16c0 kernel/rcu/tree.c:2743 > __do_softirq+0x1d7/0x93b kernel/softirq.c:558 > invoke_softirq kernel/softirq.c:432 [inline] > __irq_exit_rcu kernel/softirq.c:636 [inline] > irq_exit_rcu+0xf2/0x130 kernel/softirq.c:648 > sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:109= 7 > > asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtent= ry.h:638 > RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:717 > Code: 1b 51 88 f8 e9 6f fe ff ff e8 11 51 88 f8 e9 3d fe ff ff e8 17 > 31 fd ff cc cc cc cc cc cc cc eb 07 0f 00 2d 47 99 50 00 fb f4 0f > 1f 40 00 41 54 be 08 00 00 00 53 65 48 8b 1c 25 40 f0 01 00 > RSP: 0018:ffffffff8b607e28 EFLAGS: 00000206 > RAX: 000000000006117b RBX: 0000000000000000 RCX: ffffffff8932d572 > RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 > RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed100c7c6542 > R10: ffff888063e32a0b R11: ffffed100c7c6541 R12: 0000000000000000 > R13: 0000000000000000 R14: ffffffff8d6d8590 R15: 0000000000000000 > default_idle_call+0xc4/0x420 kernel/sched/idle.c:112 > cpuidle_idle_call kernel/sched/idle.c:194 [inline] > do_idle+0x3f9/0x570 kernel/sched/idle.c:306 > cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 > start_kernel+0x47a/0x49b init/main.c:1141 > secondary_startup_64_no_verify+0xb0/0xbb > ---------------- > Code disassembly (best guess): > 0: 1b 51 88 sbb -0x78(%rcx),%edx > 3: f8 clc > 4: e9 6f fe ff ff jmpq 0xfffffe78 > 9: e8 11 51 88 f8 callq 0xf888511f > e: e9 3d fe ff ff jmpq 0xfffffe50 > 13: e8 17 31 fd ff callq 0xfffd312f > 18: cc int3 > 19: cc int3 > 1a: cc int3 > 1b: cc int3 > 1c: cc int3 > 1d: cc int3 > 1e: cc int3 > 1f: eb 07 jmp 0x28 > 21: 0f 00 2d 47 99 50 00 verw 0x509947(%rip) # 0x50996f > 28: fb sti > 29: f4 hlt > * 2a: c3 retq <-- trapping instruction > 2b: 0f 1f 40 00 nopl 0x0(%rax) > 2f: 41 54 push %r12 > 31: be 08 00 00 00 mov $0x8,%esi > 36: 53 push %rbx > 37: 65 48 8b 1c 25 40 f0 mov %gs:0x1f040,%rbx > 3e: 01 00% Hello=C2=A0 Christoph This is the details of the test, Hope it helps you