Re: [PATCH v2] cpupower: Fix cpuidle_set to accept only numeric values for idle-set operation.

From: Shuah Khan
Date: Mon Apr 10 2023 - 18:52:15 EST


On 4/10/23 06:10, Korrapati Likhitha wrote:
From: Likhitha Korrapati <likhitha@xxxxxxxxxxxxx>

For both the d and e options in 'cpupower idle_set' command, an
atoi() conversion is done without checking if the input argument
is all numeric. So, an atoi conversion is done on any character
provided as input and the CPU idle_set operation continues with
that integer value, which may not be what is intended or entirely
correct.

The output of cpuidle-set before patch is as follows:

[root@xxx cpupower]# cpupower idle-set -e 1$
Idlestate 1 enabled on CPU 0
[snip]
Idlestate 1 enabled on CPU 47

[root@xxx cpupower]# cpupower idle-set -e 11
Idlestate 11 not available on CPU 0
[snip]
Idlestate 11 not available on CPU 47

[root@xxx cpupower]# cpupower idle-set -d 12
Idlestate 12 not available on CPU 0
[snip]
Idlestate 12 not available on CPU 47

[root@xxx cpupower]# cpupower idle-set -d qw
Idlestate 0 disabled on CPU 0
[snip]
Idlestate 0 disabled on CPU 47

This patch adds a check for both d and e options in cpuidle-set.c
to see that the idle_set value is all numeric before doing a
string-to-int conversion.

The output of cpuidle-set after the patch is as below:

[root@xxx cpupower]# ./cpupower idle-set -e 1$
Bad idle_set value: 1$. Integer expected

[root@xxx cpupower]# ./cpupower idle-set -e 11
Idlestate 11 not available on CPU 0
[snip]
Idlestate 11 not available on CPU 47

[root@xxx cpupower]# ./cpupower idle-set -d 12
Idlestate 12 not available on CPU 0
[snip]
Idlestate 12 not available on CPU 47

[root@xxx cpupower]# ./cpupower idle-set -d qw
Bad idle_set value: qw. Integer expected

Signed-off-by: Likhitha Korrapati <likhitha@xxxxxxxxxxxxx>
Signed-off-by: Brahadambal Srinivasan <latha@xxxxxxxxxxxxxxxxxx>
Reported-by: Pavithra Prakash <pavrampu@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Rick Lindsley <ricklind@xxxxxxxxxxxxxxxxxx>
---

** changes since v1 [1] **

- Addressed reviewed comments from v1.
- Slightly reworded the commit for clarity.

[1] https://lore.kernel.org/all/20210105122452.8687-1-latha@xxxxxxxxxxxxxxxxxx/

tools/power/cpupower/utils/cpuidle-set.c | 25 ++++++++++++++++----
tools/power/cpupower/utils/helpers/helpers.h | 8 +++++++
tools/power/cpupower/utils/helpers/misc.c | 17 +++++++++++++
3 files changed, 45 insertions(+), 5 deletions(-)

diff --git a/tools/power/cpupower/utils/cpuidle-set.c b/tools/power/cpupower/utils/cpuidle-set.c
index 46158928f9ad..1bfe16d27c2d 100644
--- a/tools/power/cpupower/utils/cpuidle-set.c
+++ b/tools/power/cpupower/utils/cpuidle-set.c
@@ -47,7 +47,12 @@ int cmd_idle_set(int argc, char **argv)
break;
}
param = ret;
- idlestate = atoi(optarg);
+ if (is_stringnumeric(optarg))
+ idlestate = atoi(optarg);
+ else {
+ printf(_("Bad idle_set value: %s. Integer expected\n"), optarg);
+ exit(EXIT_FAILURE);
+ }

Why can't we do this once instead of duplicating the code under
'd' and 'e'

Also have you tried using isdigit(idlestate) - works just fine
for me.

diff --git a/tools/power/cpupower/utils/cpuidle-set.c b/tools/power/cpupower/utils/cpuidle-set.c
index 46158928f9ad..01b344efc1b1 100644
--- a/tools/power/cpupower/utils/cpuidle-set.c
+++ b/tools/power/cpupower/utils/cpuidle-set.c
@@ -95,6 +95,11 @@ int cmd_idle_set(int argc, char **argv)
exit(EXIT_FAILURE);
}
+ if(!isdigit(idlestate)) {
+ printf("invalid idlestate specified\n");
+ exit(EXIT_FAILURE);
+ }
+
get_cpustate();
/* Default is: set all CPUs */

thanks,
-- Shuah