From: syzbot <syzbot+6884a790570df1022b2d@syzkaller.appspotmail.com>
To: arnd@arndb.de, gregkh@linuxfoundation.org, jrdr.linux@gmail.com,
keescook@chromium.org, kstewart@linuxfoundation.org,
linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org,
mawilcox@microsoft.com, syzkaller-bugs@googlegroups.com,
tglx@linutronix.de, viro@zeniv.linux.org.uk, zaitcev@redhat.com
Subject: possible deadlock in __might_fault (3)
Date: Thu, 30 Aug 2018 11:31:03 -0700 [thread overview]
Message-ID: <00000000000008e7340574ab473a@google.com> (raw)
Hello,
syzbot found the following crash on:
HEAD commit: 58c3f14f86c9 Merge tag 'riscv-for-linus-4.19-rc2' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13795092400000
kernel config: https://syzkaller.appspot.com/x/.config?x=531a917630d2a492
dashboard link: https://syzkaller.appspot.com/bug?extid=6884a790570df1022b2d
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
userspace arch: i386
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+6884a790570df1022b2d@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
4.19.0-rc1+ #118 Not tainted
------------------------------------------------------
syz-executor7/25985 is trying to acquire lock:
00000000bd99782f (&mm->mmap_sem){++++}, at: __might_fault+0xfb/0x1e0
mm/memory.c:4577
but task is already holding lock:
00000000a8e804bc (&rp->fetch_lock){+.+.}, at: mon_bin_fetch+0x37/0x340
drivers/usb/mon/mon_bin.c:909
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&rp->fetch_lock){+.+.}:
__mutex_lock_common kernel/locking/mutex.c:925 [inline]
__mutex_lock+0x171/0x1700 kernel/locking/mutex.c:1073
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088
mon_bin_vma_fault+0xdc/0x4a0 drivers/usb/mon/mon_bin.c:1237
__do_fault+0xee/0x450 mm/memory.c:3240
do_read_fault mm/memory.c:3652 [inline]
do_fault mm/memory.c:3752 [inline]
handle_pte_fault mm/memory.c:3983 [inline]
__handle_mm_fault+0x2b4a/0x4350 mm/memory.c:4107
handle_mm_fault+0x53e/0xc80 mm/memory.c:4144
faultin_page mm/gup.c:518 [inline]
__get_user_pages+0x823/0x1b50 mm/gup.c:718
populate_vma_page_range+0x2db/0x3d0 mm/gup.c:1222
__mm_populate+0x286/0x4d0 mm/gup.c:1270
mm_populate include/linux/mm.h:2307 [inline]
vm_mmap_pgoff+0x27f/0x2c0 mm/util.c:362
ksys_mmap_pgoff+0x4da/0x660 mm/mmap.c:1585
__do_sys_mmap_pgoff mm/mmap.c:1596 [inline]
__se_sys_mmap_pgoff mm/mmap.c:1592 [inline]
__ia32_sys_mmap_pgoff+0xdd/0x1a0 mm/mmap.c:1592
do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397
entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
-> #0 (&mm->mmap_sem){++++}:
lock_acquire+0x1e4/0x4f0 kernel/locking/lockdep.c:3901
__might_fault+0x155/0x1e0 mm/memory.c:4578
mon_bin_fetch+0x26f/0x340 drivers/usb/mon/mon_bin.c:928
mon_bin_compat_ioctl+0x232/0x560 drivers/usb/mon/mon_bin.c:1170
__do_compat_sys_ioctl fs/compat_ioctl.c:1419 [inline]
__se_compat_sys_ioctl fs/compat_ioctl.c:1365 [inline]
__ia32_compat_sys_ioctl+0x221/0x640 fs/compat_ioctl.c:1365
do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397
entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
other info that might help us debug this:
Possible unsafe locking scenario:
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending
cookies. Check SNMP counters.
CPU0 CPU1
---- ----
lock(&rp->fetch_lock);
lock(&mm->mmap_sem);
lock(&rp->fetch_lock);
lock(&mm->mmap_sem);
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending
cookies. Check SNMP counters.
*** DEADLOCK ***
1 lock held by syz-executor7/25985:
#0: 00000000a8e804bc (&rp->fetch_lock){+.+.}, at: mon_bin_fetch+0x37/0x340
drivers/usb/mon/mon_bin.c:909
stack backtrace:
CPU: 1 PID: 25985 Comm: syz-executor7 Not tainted 4.19.0-rc1+ #118
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
print_circular_bug.isra.34.cold.55+0x1bd/0x27d
kernel/locking/lockdep.c:1222
check_prev_add kernel/locking/lockdep.c:1862 [inline]
check_prevs_add kernel/locking/lockdep.c:1975 [inline]
validate_chain kernel/locking/lockdep.c:2416 [inline]
__lock_acquire+0x3449/0x5020 kernel/locking/lockdep.c:3412
lock_acquire+0x1e4/0x4f0 kernel/locking/lockdep.c:3901
__might_fault+0x155/0x1e0 mm/memory.c:4578
mon_bin_fetch+0x26f/0x340 drivers/usb/mon/mon_bin.c:928
mon_bin_compat_ioctl+0x232/0x560 drivers/usb/mon/mon_bin.c:1170
__do_compat_sys_ioctl fs/compat_ioctl.c:1419 [inline]
__se_compat_sys_ioctl fs/compat_ioctl.c:1365 [inline]
__ia32_compat_sys_ioctl+0x221/0x640 fs/compat_ioctl.c:1365
do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397
entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f2aca9
Code: 55 08 8b 88 64 cd ff ff 8b 98 68 cd ff ff 89 c8 85 d2 74 02 89 0a 5b
5d c3 8b 04 24 c3 8b 1c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90
90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f5f260cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000c00c9207
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending
cookies. Check SNMP counters.
RDX: 0000000020000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge0 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge0 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge0 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge0 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge0 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge0 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge0 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
device bridge0 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with
syzbot.
next reply other threads:[~2018-08-30 18:31 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-30 18:31 syzbot [this message]
2018-09-01 7:49 ` possible deadlock in __might_fault (3) syzbot
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=00000000000008e7340574ab473a@google.com \
--to=syzbot+6884a790570df1022b2d@syzkaller.appspotmail.com \
--cc=arnd@arndb.de \
--cc=gregkh@linuxfoundation.org \
--cc=jrdr.linux@gmail.com \
--cc=keescook@chromium.org \
--cc=kstewart@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=mawilcox@microsoft.com \
--cc=syzkaller-bugs@googlegroups.com \
--cc=tglx@linutronix.de \
--cc=viro@zeniv.linux.org.uk \
--cc=zaitcev@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox