Re: WARNING in ion_buffer_destroy

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 01/09/2018 02:58 PM, syzbot wrote:
Hello,

syzkaller hit the following crash on 06d41862286aa7bc634a1dd9e6e7e96f925ef30a
git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers


IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+cd8bcd40cb049efa2770@xxxxxxxxxxxxxxxxxxxxxxxxx
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.

audit: type=1400 audit(1515538424.230:7): avc:  denied  { map } for  pid=3499 comm="syzkaller239906" path="/root/syzkaller239906633" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
WARNING: CPU: 0 PID: 1467 at drivers/staging/android/ion/ion.c:122 ion_buffer_destroy+0xd4/0x190 drivers/staging/android/ion/ion.c:122
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 1467 Comm: ion_system_heap Not tainted 4.15.0-rc7-next-20180109+ #92
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+0x194/0x257 lib/dump_stack.c:53
  panic+0x1e4/0x41c kernel/panic.c:183
  __warn+0x1dc/0x200 kernel/panic.c:547
  report_bug+0x211/0x2d0 lib/bug.c:184
  fixup_bug.part.11+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+0x22/0x40 arch/x86/entry/entry_64.S:1079
RIP: 0010:ion_buffer_destroy+0xd4/0x190 drivers/staging/android/ion/ion.c:122
RSP: 0018:ffff8801d3a9fd28 EFLAGS: 00010293
RAX: ffff8801d39ee700 RBX: ffff8801c00e57c0 RCX: ffffffff8415d2a4
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801d5ada5b8
RBP: ffff8801d3a9fd50 R08: 0000000000000000 R09: 1ffff1003a753f8a
R10: ffff8801d3a9fc18 R11: 0000000000000000 R12: ffffffff86e4c980
R13: ffff8801d5ada580 R14: ffff8801c00e57e0 R15: 0000000000000001
  ion_heap_deferred_free+0x290/0x650 drivers/staging/android/ion/ion_heap.c:236
  kthread+0x33c/0x400 kernel/kthread.c:238
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524
Dumping ftrace buffer:
    (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

This is catching that a buffer was freed with an existing kernel
map still present. The problem is this can easily be triggered from
userspace by calling DMA_BUF_SYNC_START without calling
DMA_BUF_SYNC_END. It's clearly not appropriate for userspace to
be able to trigger a warning so I'll see about switching this to
a pr_warn_once.

Thanks,
Laura

_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel




[Index of Archives]     [Linux Driver Backports]     [DMA Engine]     [Linux GPIO]     [Linux SPI]     [Video for Linux]     [Linux USB Devel]     [Linux Coverity]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]
  Powered by Linux