2023-10-06 15:30:24

by Ian Rogers

[permalink] [raw]
Subject: Re: [PATCH v1] perf parse-events: Avoid erange from hex numbers

On Thu, Sep 7, 2023 at 2:05 PM Ian Rogers <[email protected]> wrote:
>
> We specify that a "num_hex" comprises 1 or more digits, however, that
> allows strtoull to fail with ERANGE. Limit the number of hex digits to
> being between 1 and 16.
>
> Before:
> ```
> $ perf stat -e 'cpu/rE7574c47490475745/' true
> perf: util/parse-events.c:215: fix_raw: Assertion `errno == 0' failed.
> Aborted (core dumped)
> ```
>
> After:
> ```
> $ perf stat -e 'cpu/rE7574c47490475745/' true
> event syntax error: 'cpu/rE7574c47490475745/'
> \___ Bad event or PMU
>
> Unable to find PMU or event on a PMU of 'cpu'
>
> Initial error:
> event syntax error: 'cpu/rE7574c47490475745/'
> \___ unknown term 'rE7574c47490475745' for pmu 'cpu'
>
> valid terms: event,pc,edge,offcore_rsp,ldlat,inv,umask,frontend,cmask,config,config1,config2,config3,name,period,percore,metric-id
> Run 'perf list' for a list of valid events
>
> Usage: perf stat [<options>] [<command>]
>
> -e, --event <event> event selector. use 'perf list' to list available events
> ```
>
> Issue found through fuzz testing.
>
> Signed-off-by: Ian Rogers <[email protected]>

Hi, would be nice to land this.

Thanks!
Ian

> ---
> tools/perf/util/parse-events.l | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
> index 4ef4b6f171a0..f7df52b22c39 100644
> --- a/tools/perf/util/parse-events.l
> +++ b/tools/perf/util/parse-events.l
> @@ -156,8 +156,8 @@ event_pmu [^,{}/]+[/][^/]*[/][^,{}/]*
> event [^,{}/]+
>
> num_dec [0-9]+
> -num_hex 0x[a-fA-F0-9]+
> -num_raw_hex [a-fA-F0-9]+
> +num_hex 0x[a-fA-F0-9]{1,16}
> +num_raw_hex [a-fA-F0-9]{1,16}
> name [a-zA-Z_*?\[\]][a-zA-Z0-9_*?.\[\]!\-]*
> name_tag [\'][a-zA-Z_*?\[\]][a-zA-Z0-9_*?\-,\.\[\]:=]*[\']
> name_minus [a-zA-Z_*?][a-zA-Z0-9\-_*?.:]*
> --
> 2.42.0.283.g2d96d420d3-goog
>


2023-10-06 19:08:00

by Namhyung Kim

[permalink] [raw]
Subject: Re: [PATCH v1] perf parse-events: Avoid erange from hex numbers

Hi Ian,

On Fri, Oct 6, 2023 at 8:30 AM Ian Rogers <[email protected]> wrote:
>
> On Thu, Sep 7, 2023 at 2:05 PM Ian Rogers <[email protected]> wrote:
> >
> > We specify that a "num_hex" comprises 1 or more digits, however, that
> > allows strtoull to fail with ERANGE. Limit the number of hex digits to
> > being between 1 and 16.
> >
> > Before:
> > ```
> > $ perf stat -e 'cpu/rE7574c47490475745/' true
> > perf: util/parse-events.c:215: fix_raw: Assertion `errno == 0' failed.
> > Aborted (core dumped)
> > ```
> >
> > After:
> > ```
> > $ perf stat -e 'cpu/rE7574c47490475745/' true
> > event syntax error: 'cpu/rE7574c47490475745/'
> > \___ Bad event or PMU
> >
> > Unable to find PMU or event on a PMU of 'cpu'
> >
> > Initial error:
> > event syntax error: 'cpu/rE7574c47490475745/'
> > \___ unknown term 'rE7574c47490475745' for pmu 'cpu'
> >
> > valid terms: event,pc,edge,offcore_rsp,ldlat,inv,umask,frontend,cmask,config,config1,config2,config3,name,period,percore,metric-id
> > Run 'perf list' for a list of valid events
> >
> > Usage: perf stat [<options>] [<command>]
> >
> > -e, --event <event> event selector. use 'perf list' to list available events
> > ```
> >
> > Issue found through fuzz testing.
> >
> > Signed-off-by: Ian Rogers <[email protected]>

Acked-by: Namhyung Kim <[email protected]>

Thanks,
Namhyung

2023-10-12 17:21:27

by Namhyung Kim

[permalink] [raw]
Subject: Re: [PATCH v1] perf parse-events: Avoid erange from hex numbers

On Fri, Oct 6, 2023 at 12:05 PM Namhyung Kim <[email protected]> wrote:
>
> Hi Ian,
>
> On Fri, Oct 6, 2023 at 8:30 AM Ian Rogers <[email protected]> wrote:
> >
> > On Thu, Sep 7, 2023 at 2:05 PM Ian Rogers <[email protected]> wrote:
> > >
> > > We specify that a "num_hex" comprises 1 or more digits, however, that
> > > allows strtoull to fail with ERANGE. Limit the number of hex digits to
> > > being between 1 and 16.
> > >
> > > Before:
> > > ```
> > > $ perf stat -e 'cpu/rE7574c47490475745/' true
> > > perf: util/parse-events.c:215: fix_raw: Assertion `errno == 0' failed.
> > > Aborted (core dumped)
> > > ```
> > >
> > > After:
> > > ```
> > > $ perf stat -e 'cpu/rE7574c47490475745/' true
> > > event syntax error: 'cpu/rE7574c47490475745/'
> > > \___ Bad event or PMU
> > >
> > > Unable to find PMU or event on a PMU of 'cpu'
> > >
> > > Initial error:
> > > event syntax error: 'cpu/rE7574c47490475745/'
> > > \___ unknown term 'rE7574c47490475745' for pmu 'cpu'
> > >
> > > valid terms: event,pc,edge,offcore_rsp,ldlat,inv,umask,frontend,cmask,config,config1,config2,config3,name,period,percore,metric-id
> > > Run 'perf list' for a list of valid events
> > >
> > > Usage: perf stat [<options>] [<command>]
> > >
> > > -e, --event <event> event selector. use 'perf list' to list available events
> > > ```
> > >
> > > Issue found through fuzz testing.
> > >
> > > Signed-off-by: Ian Rogers <[email protected]>
>
> Acked-by: Namhyung Kim <[email protected]>

Applied to perf-tools-next, thanks!