Search Linux Wireless

Re: [PATCH] staging: rtl8712: prevent buffer overrun in recvbuf2recvframe

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

 



On 05/23/2015 12:24 PM, Haggai Eran wrote:
On 20 May 2015 at 22:20, Haggai Eran <haggai.eran@xxxxxxxxx> wrote:
On 20 May 2015 at 19:39, Larry Finger <Larry.Finger@xxxxxxxxxxxx> wrote:
On 05/20/2015 01:17 AM, Haggai Eran wrote:

On May 19, 2015 08:47, "Haggai Eran" <haggai.eran@xxxxxxxxx
<mailto:haggai.eran@xxxxxxxxx>> wrote:
  >
  > With an RTL8191SU USB adaptor, sometimes the hints for a fragmented
  > packet are set, but the packet length is too large. Truncate the packet
  > to prevent memory corruption.
  >
  > Signed-off-by: Haggai Eran <haggai.eran@xxxxxxxxx
<mailto:haggai.eran@xxxxxxxxx>>
  > ---
  >
  > Hi,
  >
  > I think this solves the issue for me. I'll test it more thoroughly
later. I
  > still don't know why a fragmented packet has such a large pkt_len value
though.
  >
  > Thanks,
  > Haggai
  >

I guess I was too quick with this patch. It prevents the kernel page
faults, but
with it I still see sometimes the connectivity disappear for a minute or
two.


Is anything logged when that happens?
No. I get once in a while the other corrupted entries I told you
about, but nothing special to these freezes

I'm still trying to see where that magic number of 1658 comes from, and how
that affects the RX buffer size.

I tried to look at the new driver (rtl8192su), but it doesn't seem to
handle this more-fragment bit at all.

When I unconditionally set alloc_sz to tmp_len as in the attached patch (I
remembered to refresh it this time), nothing bad has happened here yet. What
happens on your box?

The same freezes still occur.

I think the freezes I saw weren't related to the same issue. I was
running a debugging kernel, and I saw the same freezes also with a
different wifi adaptor. After switching to a non-debugging kernel, and
using your patch, the freezes stopped.

That is good news. Perhaps the debugging kernel is overflowing the stack. Did your debugging kernel have "Check for stack overflows" set in the "Memory Debugging" section of the configuration? I did not have that turned on until today, but it seems like a good idea.

Do you want to prepare the final version of the patch, or should I?

Larry

--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Host AP]     [ATH6KL]     [Linux Wireless Personal Area Network]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Linux Kernel]     [IDE]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite Hiking]     [MIPS Linux]     [ARM Linux]     [Linux RAID]

  Powered by Linux