From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <3zPO_WgkbAI8BHI3t44xAt881w.z77z4xDBxAv76Cx6C.v75@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com> ARC-Seal: i=1; a=rsa-sha256; t=1522529228; cv=none; d=google.com; s=arc-20160816; b=VRBKN3LdjnrpuehTQVB7Cq37CJz+I0MrH3o/K2genCha/AQOD69oWXdaGTtdBgoN63 m+num88UQHr/4FX95skHxalHMBC2vZC1w6wAJEc8Pv8z7bKwaoUdr7ni9tWqWjdBwm/v pXtiMEkAo95arZsgPRxSHCIJ8XnVt/xM/GsJF+FOHel9zT/JeykBSCD4ulwivbWbMm9r XfpQJckdTH8jCDsDmbSrEWG4e11TMnAReroNnFX1Wu9AkoN8HohwveFAYJy+rg3bOUx4 7WL7jOyTs3LjSVisv1PwS/8FbyKRk1IZYPpTFrSPqQOXgZyGQ9Cu6/b1o0Jl7zaOA9GW ctQQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=to:from:subject:message-id:date:mime-version :arc-authentication-results; bh=SDqk2Acmq9n2NJAOB+56f8CKau5AyTwRdhJagMF4gZ8=; b=yhKfCM4VBPUfkc3J/1R8bYfshlMweML9x9SV5qo7GsHgusO1hZEm0fFzx+HZaBJX1z cTsk8VVN95vYDooLpTQrBCAzcURnYDxqCe6E8aAlMGIjMpIr5+e/11I1Mm2tpRNfR1dL 8SZiF9O6+xYZVoLHcFW4dGwO93U5o3sZkCkXlz+by0Q2+ANxtEAzdqm/DRLd6m4MnyQ7 BnlZtJ3sMLxfXNUWPK0ambDUg8lPgqFM1Qb3l1RehwF2b6AmmAnFxOuPyUv1EMJjiouC uaJsSrThzMCuwwPFPa4PpRBzDpjU9AHvq26cgnTysZxHu+Ho2m54y0kUycVvLu3APSPW 1sYQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of 3zpo_wgkbai8bhi3t44xat881w.z77z4xdbxav76cx6c.v75@m3kw2wvrgufz5godrsrytgd7.apphosting.bounces.google.com designates 209.85.220.69 as permitted sender) smtp.mailfrom=3zPO_WgkbAI8BHI3t44xAt881w.z77z4xDBxAv76Cx6C.v75@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=appspotmail.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of 3zpo_wgkbai8bhi3t44xat881w.z77z4xdbxav76cx6c.v75@m3kw2wvrgufz5godrsrytgd7.apphosting.bounces.google.com designates 209.85.220.69 as permitted sender) smtp.mailfrom=3zPO_WgkbAI8BHI3t44xAt881w.z77z4xDBxAv76Cx6C.v75@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=appspotmail.com X-Google-Smtp-Source: AIpwx4+BASpFC9wKzv/sC3ODPZ0QCamqHULZ5Uxb8OVgSmnqCFEo8I6NMcwo78R/fCJ3Q8xyoYa1OQHdqRSSmEj70hNpz+PXOPgR MIME-Version: 1.0 Date: Sat, 31 Mar 2018 13:47:08 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <94eb2c054604d4ac000568bb758c@google.com> Subject: WARNING: refcount bug in put_pid_ns From: syzbot To: gregkh@linuxfoundation.org, kstewart@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, pombredanne@nexb.com, syzkaller-bugs@googlegroups.com, tglx@linutronix.de Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1596487607739609259?= X-GMAIL-MSGID: =?utf-8?q?1596487608917142866?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hello, syzbot hit the following crash on upstream commit 9dd2326890d89a5179967c947dab2bab34d7ddee (Fri Mar 30 17:29:47 2018 +0000) Merge tag 'ceph-for-4.16-rc8' of git://github.com/ceph/ceph-client syzbot dashboard link: https://syzkaller.appspot.com/bug?extid=66a731f39da94bb14930 So far this crash happened 6 times on upstream. syzkaller reproducer: https://syzkaller.appspot.com/x/repro.syz?id=6405492943355904 Raw console output: https://syzkaller.appspot.com/x/log.txt?id=5483914026024960 Kernel config: https://syzkaller.appspot.com/x/.config?id=-2760467897697295172 compiler: gcc (GCC) 7.1.1 20170620 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+66a731f39da94bb14930@syzkaller.appspotmail.com It will help syzbot understand when the bug is fixed. See footer for details. If you forward the report, please keep this part and the footer. __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 4478 at lib/refcount.c:187 refcount_sub_and_test+0x167/0x1b0 lib/refcount.c:187 should_failslab+0xec/0x120 mm/failslab.c:32 Kernel panic - not syncing: panic_on_warn set ... slab_pre_alloc_hook mm/slab.h:422 [inline] slab_alloc mm/slab.c:3366 [inline] kmem_cache_alloc+0x47/0x760 mm/slab.c:3540 kmem_cache_zalloc include/linux/slab.h:691 [inline] fill_pool lib/debugobjects.c:110 [inline] __debug_object_init+0xa99/0x1040 lib/debugobjects.c:339 debug_object_init+0x17/0x20 lib/debugobjects.c:391 __init_work+0x2b/0x60 kernel/workqueue.c:506 __memcg_schedule_kmem_cache_create mm/memcontrol.c:2203 [inline] memcg_schedule_kmem_cache_create mm/memcontrol.c:2223 [inline] memcg_kmem_get_cache+0x571/0x890 mm/memcontrol.c:2285 slab_pre_alloc_hook mm/slab.h:427 [inline] slab_alloc mm/slab.c:3366 [inline] kmem_cache_alloc+0x186/0x760 mm/slab.c:3540 proc_alloc_inode+0x1b/0x190 fs/proc/inode.c:63 alloc_inode+0x65/0x180 fs/inode.c:209 new_inode_pseudo+0x69/0x190 fs/inode.c:890 proc_get_inode+0x20/0x620 fs/proc/inode.c:436 proc_fill_super+0x1dd/0x300 fs/proc/inode.c:502 mount_ns+0xc4/0x190 fs/super.c:1036 proc_mount+0x7a/0x90 fs/proc/root.c:101 mount_fs+0x66/0x2d0 fs/super.c:1222 vfs_kern_mount.part.26+0xc6/0x4a0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:3292 [inline] kern_mount_data+0x50/0xb0 fs/namespace.c:3292 pid_ns_prepare_proc+0x1e/0x80 fs/proc/root.c:222 alloc_pid+0x87e/0xa00 kernel/pid.c:208 copy_process.part.38+0x2516/0x4bd0 kernel/fork.c:1807 copy_process kernel/fork.c:1606 [inline] _do_fork+0x1f7/0xf70 kernel/fork.c:2087 SYSC_clone kernel/fork.c:2194 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2188 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x454e79 RSP: 002b:00007fe845e3ec68 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fe845e3f6d4 RCX: 0000000000454e79 RDX: 00000000200008c0 RSI: 0000000020000800 RDI: 000000002000c100 RBP: 000000000072bea0 R08: 0000000020000940 R09: 0000000000000000 R10: 0000000020000900 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000051 R14: 00000000006f2838 R15: 0000000000000028 CPU: 0 PID: 4478 Comm: syz-executor1 Not tainted 4.16.0-rc7+ #372 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 panic+0x1e4/0x41c kernel/panic.c:183 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 __warn+0x1dc/0x200 kernel/panic.c:547 report_bug+0x1f4/0x2b0 lib/bug.c:186 fixup_bug.part.10+0x37/0x80 arch/x86/kernel/traps.c:178 fixup_bug arch/x86/kernel/traps.c:247 [inline] do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:986 RIP: 0010:refcount_sub_and_test+0x167/0x1b0 lib/refcount.c:187 RSP: 0018:ffff8801ad017318 EFLAGS: 00010282 RAX: dffffc0000000008 RBX: 0000000000000000 RCX: ffffffff815b193e RDX: 0000000000000000 RSI: 1ffff10035a02e13 RDI: 1ffff10035a02de8 RBP: ffff8801ad0173a8 R08: 0000000000000000 R09: 0000000000000000 R10: ffff8801ad0172d0 R11: 0000000000000000 R12: 1ffff10035a02e64 R13: 00000000ffffffff R14: 0000000000000001 R15: ffff8801ad2b0630 refcount_dec_and_test+0x1a/0x20 lib/refcount.c:212 kref_put include/linux/kref.h:69 [inline] put_pid_ns+0x9d/0xc0 kernel/pid_namespace.c:192 free_nsproxy+0xfa/0x1f0 kernel/nsproxy.c:182 switch_task_namespaces+0x9d/0xc0 kernel/nsproxy.c:229 exit_task_namespaces+0x17/0x20 kernel/nsproxy.c:234 copy_process.part.38+0x3aba/0x4bd0 kernel/fork.c:1988 copy_process kernel/fork.c:1606 [inline] _do_fork+0x1f7/0xf70 kernel/fork.c:2087 SYSC_clone kernel/fork.c:2194 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2188 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x454e79 RSP: 002b:00007f64a187cc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f64a187d6d4 RCX: 0000000000454e79 RDX: 00000000200008c0 RSI: 0000000020000800 RDI: 000000002000c100 RBP: 000000000072bea0 R08: 0000000020000940 R09: 0000000000000000 R10: 0000000020000900 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000051 R14: 00000000006f2838 R15: 0000000000000028 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds.. --- This bug is generated by a dumb bot. 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