Re: [PATCH v2] librte_cmdline: FreeBSD Fix oveflow when size of command result structure is greater than BUFSIZ

[Olivier MATZ <olivier.matz-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>]

Hi Alan,
On 11/10/2014 10:19 AM, Alan Carew wrote:
> When using test-pmd with flow director in FreeBSD, the application will
> segfault/Bus error while parsing the command-line. This is due to how
> each commands result structure is represented during parsing, where the offsets
> for each tokens value is stored in a character array(char result_buf[BUFSIZ])
> in cmdline_parse()(./lib/librte_cmdline/cmdline_parse.c).
> 
> The overflow occurs where BUFSIZ is less than the size of a commands result
> structure, in this case "struct cmd_pkt_filter_result"
> (app/test-pmd/cmdline.c) is 1088 bytes and BUFSIZ on FreeBSD is 1024 bytes as
> opposed to 8192 bytes on Linux.
> 
> The problem can be reproduced by running test-pmd on FreeBSD:
> ./testpmd -c 0x3 -n 4 -- -i --portmask=0x3 --pkt-filter-mode=perfect
> And adding a filter:
> add_perfect_filter 0 udp src 192.168.0.0 1024 dst 192.168.0.0 1024 flexbytes
> 0x800 vlan 0 queue 0 soft 0x17
> 
> This patch removes the OS dependency on BUFSIZ and defines and uses a
> library #define CMDLINE_PARSE_RESULT_BUFSIZE 8192
> 
> Added boundary checking to ensure this buffer size cannot overflow, with
> an error message being produced.
> 
> Suggested-by: Olivier MATZ <olivier.matz-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>
> http://git.droids-corp.org/?p=libcmdline.git;a=commitdiff;h=b1d5b169352e57df3fc14c51ffad4b83f3e5613f
> 
> Signed-off-by: Alan Carew <alan.carew-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>

I think some checks are missing compared to the original patch. The
cmdline_parse_xxx() functions should be modified too. Please see a
v3 in my next email.

Regards,
Olivier