On Wed, 20 Sep 2017 18:23:56 -0700
Julien Fortin <jul...@cumulusnetworks.com> wrote:
> From: Julien Fortin <jul...@cumulusnetworks.com>
>
> The ip monitor didn't call `new_json_obj` (even for in non json context),
> so the static FILE* _fp variable wasn't initialized, thus raising a
> SIGSEGV in ipaddress.c. This patch should fix this issue for good, new
> paths won't have to call `new_json_obj`.
>
> $ ip -t mon label link
> fmt=fmt@entry=0x45460d "%d: ", value=<optimized out>) at
> ip_print.c:132
> #3 0x000000000040ccd2 in print_int (value=<optimized out>,
> fmt=0x45460d "%d: ", key=0x4545fc "ifindex", t=PRINT_ANY) at ip_common.h:189
> #4 print_linkinfo (who=<optimized out>, n=0x7fffffffa380,
> arg=0x7ffff77a82a0 <_IO_2_1_stdout_>) at ipaddress.c:1107
> #5 0x0000000000422e13 in accept_msg (who=0x7fffffff8320,
> ctrl=0x7fffffff8310, n=0x7fffffffa380, arg=0x7ffff77a82a0 <_IO_2_1_stdout_>)
> at ipmonitor.c:89
> #6 0x000000000044c58f in rtnl_listen (rtnl=0x672160 <rth>,
> handler=handler@entry=0x422c70 <accept_msg>, jarg=0x7ffff77a82a0
> <_IO_2_1_stdout_>)
> at libnetlink.c:761
> #7 0x00000000004233db in do_ipmonitor (argc=<optimized out>,
> argv=0x7fffffffe5a0) at ipmonitor.c:310
> #8 0x0000000000408f74 in do_cmd (argv0=0x7fffffffe7f5 "mon",
> argc=3, argv=0x7fffffffe588) at ip.c:116
> #9 0x0000000000408a94 in main (argc=4, argv=0x7fffffffe580) at
> ip.c:311
>
> Traceback can be seen when running the following command in a new terminal.
> $ ip link add dev br0 type bridge
>
> Fixes: 6377572f ("ip: ip_print: add new API to print JSON or regular format
> output")
> Reported-by: David Ahern <d...@cumulusnetworks.com>
> Reviewed-by: David Ahern <d...@cumulusnetworks.com>
> Signed-off-by: Julien Fortin <jul...@cumulusnetworks.com>
This is getting way more complex than it needs to be.
new_json_obj is always called with fp == stdout.
There is no reason to have the _fp at all!
Please rework new_json_obj to take only one argument.
