Re: [Qemu-devel] [PATCH] Limit memory r/w length to buffer size

[P J P]

  Hello,

+-- On Tue, 13 Oct 2015, P J P wrote --+
| Below is a proposed patch to fix this issue.
| 
| ===
| > From 88edb457a66f8ff96209a1603914171eade0658b Mon Sep 17 00:00:00 2001
| From: Prasad J Pandit <address@hidden>
| Date: Mon, 12 Oct 2015 22:56:41 +0530
| Subject: Limit memory r/w length to buffer size
| 
| GDB(1) stub communication protocol supports commands m/M to read
| and write 'len' bytes from/to the stub memory area.
| 
|    m addr,len        : read 'len' bytes from address 'addr'
|    M addr,len:<data> : write 'len' bytes of 'data' to 'addr'
| 
| Qemu stub uses automatic buffers of size 'MAX_PACKET_LENGTH=4096'
| to process these commands. Limit 'len' parameter value supplied
| by the host gdb(1) to the maximum buffer size to avoid any OOB
| buffer access.
| 
| Reported-by: Gerben van der Lubbe <address@hidden>
| Signed-off-by: Prasad J Pandit <address@hidden>
| ---
|  gdbstub.c | 2 ++
|  1 file changed, 2 insertions(+)

Could someone review it please?

Thank you.
--
Prasad J Pandit / Red Hat Product Security Team
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