Re: [PATCH] perf - ensure offset provided during probe addition is not greater than function length

[Arnaldo Carvalho de Melo <acme@infradead.org>]

Em Fri, Feb 24, 2012 at 05:03:03PM +0530, Prashanth Nageshappa escreveu:
> Can you please pick up this patch?

I'll do it, thanks,

- Arnaldo
 
> On 02/24/2012 04:02 PM, Masami Hiramatsu wrote:
> 
> > (2012/02/24 16:41), Prashanth Nageshappa wrote:
> >> perf probe allows kprobe to be inserted at any offset from a function
> >> start, which results in adding kprobes to unintended location.
> >> (example: perf probe do_fork+10000 is allowed even though size of
> >> do_fork is ~904)
> >>
> >> This patch will ensure probe addition fails when the offset specified
> >> is greater than size of the function.
> >>
> >>
> >> Signed-off-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com>
> > 
> > This seems good to me.
> > 
> > Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
> > 
> > Thank you,
> > 
> >> ---
> >>
> >>  tools/perf/util/probe-finder.c |   12 +++++++++++-
> >>  1 files changed, 11 insertions(+), 1 deletions(-)
> >>
> >> diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
> >> index 5d73262..d298f94 100644
> >> --- a/tools/perf/util/probe-finder.c
> >> +++ b/tools/perf/util/probe-finder.c
> >> @@ -672,7 +672,7 @@ static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
> >>  static int convert_to_trace_point(Dwarf_Die *sp_die, Dwarf_Addr paddr,
> >>  				  bool retprobe, struct probe_trace_point *tp)
> >>  {
> >> -	Dwarf_Addr eaddr;
> >> +	Dwarf_Addr eaddr, highaddr;
> >>  	const char *name;
> >>
> >>  	/* Copy the name of probe point */
> >> @@ -683,6 +683,16 @@ static int convert_to_trace_point(Dwarf_Die *sp_die, Dwarf_Addr paddr,
> >>  				   dwarf_diename(sp_die));
> >>  			return -ENOENT;
> >>  		}
> >> +		if (dwarf_highpc(sp_die, &highaddr) != 0) {
> >> +			pr_warning("Failed to get end address of %s\n",
> >> +				   dwarf_diename(sp_die));
> >> +			return -ENOENT;
> >> +		}
> >> +		if (paddr > highaddr) {
> >> +			pr_warning("Offset specified is greater than size of %s\n",
> >> +				   dwarf_diename(sp_die));
> >> +			return -EINVAL;
> >> +		}
> >>  		tp->symbol = strdup(name);
> >>  		if (tp->symbol == NULL)
> >>  			return -ENOMEM;
> >>
> > 
> > 
>