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Date:   Fri, 3 Jan 2020 13:04:51 +0200
From:   Mika Westerberg <mika.westerberg@linux.intel.com>
To:     Paul Menzel <pmenzel@molgen.mpg.de>
Cc:     Greg KH <greg@kroah.com>, Mathias Nyman <mathias.nyman@intel.com>,
        linux-usb@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>
Subject: Re: BUG: KASAN: use-after-free in
 xhci_trb_virt_to_dma.part.24+0x1c/0x80
Message-ID: <20200103110451.GJ465886@lahna.fi.intel.com>
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On Thu, Jan 02, 2020 at 03:10:14PM +0100, Paul Menzel wrote:
> Mika, as you fixed the other leak, any idea, how to continue from the
> kmemleak log below?
> 
> ```
> unreferenced object 0xffff8c207a1e1408 (size 8):
>   comm "systemd-udevd", pid 183, jiffies 4294667978 (age 752.292s)
>   hex dump (first 8 bytes):
>     34 01 05 00 00 00 00 00                          4.......
>   backtrace:
>     [<00000000aea7b46d>] xhci_mem_init+0xcfa/0xec0 [xhci_hcd]

There are probably better ways for doing this but you can use objdump
for example:

  $ objdump -l --prefix-addresses -j .text --disassemble=xhci_mem_init drivers/usb/host/xhci-hcd.ko

then find the offset xhci_mem_init+0xcfa. It should show you the line
numbers as well if you have compiled your kernel with debug info. This
should be close to the line that allocated the memory that was leaked.