diff mbox

perf tools: Fix potential array out of bounce accessing

Message ID 1441078184-105038-1-git-send-email-wangnan0@huawei.com
State Superseded
Headers show

Commit Message

Wang Nan Sept. 1, 2015, 3:29 a.m. UTC
There is a problem in dwarf-regs.c of sh, sparc and x86 that it is
possible to make an out-of-bound array accessing when searching
register names. This patch fixes it by replacing '<=' to '<', so when
register (number == XXX_MAX_REGS), get_arch_regstr() returns NULL.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/arch/sh/util/dwarf-regs.c    | 2 +-
 tools/perf/arch/sparc/util/dwarf-regs.c | 2 +-
 tools/perf/arch/x86/util/dwarf-regs.c   | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

Comments

Matt Fleming Sept. 1, 2015, 8:44 a.m. UTC | #1
On Tue, 01 Sep, at 03:29:44AM, Wang Nan wrote:
> There is a problem in dwarf-regs.c of sh, sparc and x86 that it is
> possible to make an out-of-bound array accessing when searching
> register names. This patch fixes it by replacing '<=' to '<', so when
> register (number == XXX_MAX_REGS), get_arch_regstr() returns NULL.
> 
> Signed-off-by: Wang Nan <wangnan0@huawei.com>
> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
> Cc: David S. Miller <davem@davemloft.net>
> Cc: Matt Fleming <matt@console-pimps.org>
> Cc: Jiri Olsa <jolsa@kernel.org>
> ---
>  tools/perf/arch/sh/util/dwarf-regs.c    | 2 +-
>  tools/perf/arch/sparc/util/dwarf-regs.c | 2 +-
>  tools/perf/arch/x86/util/dwarf-regs.c   | 2 +-
>  3 files changed, 3 insertions(+), 3 deletions(-)

Hmm, I wonder how that bug was introduced. I guess copy and paste is
probably to blame. Good catch.

Reviewed-by: Matt Fleming <matt.fleming@intel.com>
Jiri Olsa Sept. 1, 2015, 10 a.m. UTC | #2
On Tue, Sep 01, 2015 at 03:29:44AM +0000, Wang Nan wrote:
> There is a problem in dwarf-regs.c of sh, sparc and x86 that it is
> possible to make an out-of-bound array accessing when searching
> register names. This patch fixes it by replacing '<=' to '<', so when
> register (number == XXX_MAX_REGS), get_arch_regstr() returns NULL.
> 

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/
Masami Hiramatsu Sept. 1, 2015, 11:14 a.m. UTC | #3
> From: Wang Nan [mailto:wangnan0@huawei.com]

> 

> There is a problem in dwarf-regs.c of sh, sparc and x86 that it is

> possible to make an out-of-bound array accessing when searching

> register names. This patch fixes it by replacing '<=' to '<', so when

> register (number == XXX_MAX_REGS), get_arch_regstr() returns NULL.


Oops, right!

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>


Thank you!

> 

> Signed-off-by: Wang Nan <wangnan0@huawei.com>

> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>

> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

> Cc: David S. Miller <davem@davemloft.net>

> Cc: Matt Fleming <matt@console-pimps.org>

> Cc: Jiri Olsa <jolsa@kernel.org>

> ---

>  tools/perf/arch/sh/util/dwarf-regs.c    | 2 +-

>  tools/perf/arch/sparc/util/dwarf-regs.c | 2 +-

>  tools/perf/arch/x86/util/dwarf-regs.c   | 2 +-

>  3 files changed, 3 insertions(+), 3 deletions(-)

> 

> diff --git a/tools/perf/arch/sh/util/dwarf-regs.c b/tools/perf/arch/sh/util/dwarf-regs.c

> index 0d0897f..f8dfa89 100644

> --- a/tools/perf/arch/sh/util/dwarf-regs.c

> +++ b/tools/perf/arch/sh/util/dwarf-regs.c

> @@ -51,5 +51,5 @@ const char *sh_regs_table[SH_MAX_REGS] = {

>  /* Return architecture dependent register string (for kprobe-tracer) */

>  const char *get_arch_regstr(unsigned int n)

>  {

> -	return (n <= SH_MAX_REGS) ? sh_regs_table[n] : NULL;

> +	return (n < SH_MAX_REGS) ? sh_regs_table[n] : NULL;

>  }

> diff --git a/tools/perf/arch/sparc/util/dwarf-regs.c b/tools/perf/arch/sparc/util/dwarf-regs.c

> index 92eda41..b704fdb 100644

> --- a/tools/perf/arch/sparc/util/dwarf-regs.c

> +++ b/tools/perf/arch/sparc/util/dwarf-regs.c

> @@ -39,5 +39,5 @@ const char *sparc_regs_table[SPARC_MAX_REGS] = {

>   */

>  const char *get_arch_regstr(unsigned int n)

>  {

> -	return (n <= SPARC_MAX_REGS) ? sparc_regs_table[n] : NULL;

> +	return (n < SPARC_MAX_REGS) ? sparc_regs_table[n] : NULL;

>  }

> diff --git a/tools/perf/arch/x86/util/dwarf-regs.c b/tools/perf/arch/x86/util/dwarf-regs.c

> index be22dd4..a08de0a 100644

> --- a/tools/perf/arch/x86/util/dwarf-regs.c

> +++ b/tools/perf/arch/x86/util/dwarf-regs.c

> @@ -71,5 +71,5 @@ const char *x86_64_regs_table[X86_64_MAX_REGS] = {

>  /* Return architecture dependent register string (for kprobe-tracer) */

>  const char *get_arch_regstr(unsigned int n)

>  {

> -	return (n <= ARCH_MAX_REGS) ? arch_regs_table[n] : NULL;

> +	return (n < ARCH_MAX_REGS) ? arch_regs_table[n] : NULL;

>  }

> --

> 1.8.3.4
diff mbox

Patch

diff --git a/tools/perf/arch/sh/util/dwarf-regs.c b/tools/perf/arch/sh/util/dwarf-regs.c
index 0d0897f..f8dfa89 100644
--- a/tools/perf/arch/sh/util/dwarf-regs.c
+++ b/tools/perf/arch/sh/util/dwarf-regs.c
@@ -51,5 +51,5 @@  const char *sh_regs_table[SH_MAX_REGS] = {
 /* Return architecture dependent register string (for kprobe-tracer) */
 const char *get_arch_regstr(unsigned int n)
 {
-	return (n <= SH_MAX_REGS) ? sh_regs_table[n] : NULL;
+	return (n < SH_MAX_REGS) ? sh_regs_table[n] : NULL;
 }
diff --git a/tools/perf/arch/sparc/util/dwarf-regs.c b/tools/perf/arch/sparc/util/dwarf-regs.c
index 92eda41..b704fdb 100644
--- a/tools/perf/arch/sparc/util/dwarf-regs.c
+++ b/tools/perf/arch/sparc/util/dwarf-regs.c
@@ -39,5 +39,5 @@  const char *sparc_regs_table[SPARC_MAX_REGS] = {
  */
 const char *get_arch_regstr(unsigned int n)
 {
-	return (n <= SPARC_MAX_REGS) ? sparc_regs_table[n] : NULL;
+	return (n < SPARC_MAX_REGS) ? sparc_regs_table[n] : NULL;
 }
diff --git a/tools/perf/arch/x86/util/dwarf-regs.c b/tools/perf/arch/x86/util/dwarf-regs.c
index be22dd4..a08de0a 100644
--- a/tools/perf/arch/x86/util/dwarf-regs.c
+++ b/tools/perf/arch/x86/util/dwarf-regs.c
@@ -71,5 +71,5 @@  const char *x86_64_regs_table[X86_64_MAX_REGS] = {
 /* Return architecture dependent register string (for kprobe-tracer) */
 const char *get_arch_regstr(unsigned int n)
 {
-	return (n <= ARCH_MAX_REGS) ? arch_regs_table[n] : NULL;
+	return (n < ARCH_MAX_REGS) ? arch_regs_table[n] : NULL;
 }