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

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

[Prashanth Nageshappa]

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>
---

 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;

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

[Masami Hiramatsu]

(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;
> 


-- 
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com

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

[Prashanth Nageshappa]

Can you please pick up this patch?

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;
>>
> 
> 

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

[Arnaldo Carvalho de Melo]

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;
> >>
> > 
> > 
> 

[tip:perf/urgent] perf probe: Ensure offset provided is not greater than function length

[tip-bot for Prashanth Nageshappa]

Commit-ID:  26b7952494772f0e695271fbd6cf83a852f60f25
Gitweb:     http://git.kernel.org/tip/26b7952494772f0e695271fbd6cf83a852f60f25
Author:     Prashanth Nageshappa <prashanth@linux.vnet.ibm.com>
AuthorDate: Fri, 24 Feb 2012 13:11:39 +0530
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 29 Feb 2012 18:29:45 -0300

perf probe: Ensure offset provided is not greater than function length

The perf probe command 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.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/4F473F33.4060409@linux.vnet.ibm.com
Signed-off-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 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..74bd2e6 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;