linux-hardening - [PATCH] cpuidle: dt: refactor deprecated strncpy

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230913-strncpy-drivers-cpuidle-dt_idle_states-c-v1-1-d16a0dbe5658@google.com>
Date:   Wed, 13 Sep 2023 00:23:19 +0000
From:   Justin Stitt <justinstitt@...gle.com>
To:     "Rafael J. Wysocki" <rafael@...nel.org>,
        Daniel Lezcano <daniel.lezcano@...aro.org>
Cc:     linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-hardening@...r.kernel.org,
        Justin Stitt <justinstitt@...gle.com>
Subject: [PATCH] cpuidle: dt: refactor deprecated strncpy

`strncpy` is deprecated for use on NUL-terminated destination strings [1].

We should prefer more robust and less ambiguous string interfaces.

A suitable replacement is `strscpy` [2] due to the fact that it guarantees
NUL-termination on the destination buffer. With this, we can also drop
the now unnecessary `CPUIDLE_(NAME|DESC)_LEN - 1` pieces.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@...r.kernel.org
Signed-off-by: Justin Stitt <justinstitt@...gle.com>
---
Note: build-tested only
---
 drivers/cpuidle/dt_idle_states.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cpuidle/dt_idle_states.c b/drivers/cpuidle/dt_idle_states.c
index 12fec92a85fd..97feb7d8fb23 100644
--- a/drivers/cpuidle/dt_idle_states.c
+++ b/drivers/cpuidle/dt_idle_states.c
@@ -84,8 +84,8 @@ static int init_state_node(struct cpuidle_state *idle_state,
 	 *	replace with kstrdup and pointer assignment when name
 	 *	and desc become string pointers
 	 */
-	strncpy(idle_state->name, state_node->name, CPUIDLE_NAME_LEN - 1);
-	strncpy(idle_state->desc, desc, CPUIDLE_DESC_LEN - 1);
+	strscpy(idle_state->name, state_node->name, CPUIDLE_NAME_LEN);
+	strscpy(idle_state->desc, desc, CPUIDLE_DESC_LEN);
 	return 0;
 }
 

---
base-commit: 2dde18cd1d8fac735875f2e4987f11817cc0bc2c
change-id: 20230913-strncpy-drivers-cpuidle-dt_idle_states-c-c84ea03c1379

Best regards,
--
Justin Stitt <justinstitt@...gle.com>