From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 10EFE332EA7; Sat, 30 May 2026 17:58:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780163921; cv=none; b=enilvbwfuaKNxVU84IYTUTaSFRFF7LfvlFPdithDUGffxn8iQ/wi4plDPHxLgXnFFsxXYyAE5togBpmM8IR1fNuVWN4RPmn6deX/66aevFjgAJJLE3u1u1AZATk7iFDXUfLV3iZiNh1vLMxAnX6F4rQCMNtoxOesUH1rRQYR+F0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780163921; c=relaxed/simple; bh=lmVEf9p58E3zLk3G607EQGjPLRyp4PK18cQZwQZgJq4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=noXLoi3eY3560Ir5xnYnFxIT2muL4vD73jhkQLVyg3cLTFrIJlnr5itxC2Z5+xxdOv86k7GcK32oQHMgASWExDNgH+vVE1STIvyRWV5xX7zOv9T7u+LpSNOvC6K1hq8rkeKnqb0Oogh9cm5KyjvxSy+Y+f7T4wOLf0y/rIVzvX4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=dlw43Ckr; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="dlw43Ckr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5568B1F00893; Sat, 30 May 2026 17:58:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780163920; bh=ZJujABl5rm7BGQD5tX97CLQQSywD9D99/PnMk5Yqdeo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=dlw43CkrdCInT2xHa7+w6LDHvKIEmVZTmXEDAJYaj9ExHlnq0jAPp9jjQjnfwE0ku eNHSlZEh3hmGiukRkA0GmujFGjGtEuJ7iW1u5fDEGYDUr2JtY3sGUKvKsPoRW/WWCS t18pmHJ+ku2Z3W8KmPQF4zkZVg92pLdny0Q6cdks= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Petr Pavlu , Sami Tolvanen , Sasha Levin Subject: [PATCH 5.15 402/776] module: Fix freeing of charp module parameters when CONFIG_SYSFS=n Date: Sat, 30 May 2026 18:01:56 +0200 Message-ID: <20260530160250.895366720@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160240.228940103@linuxfoundation.org> References: <20260530160240.228940103@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Petr Pavlu [ Upstream commit deffe1edba626d474fef38007c03646ca5876a0e ] When setting a charp module parameter, the param_set_charp() function allocates memory to store a copy of the input value. Later, when the module is potentially unloaded, the destroy_params() function is called to free this allocated memory. However, destroy_params() is available only when CONFIG_SYSFS=y, otherwise only a dummy variant is present. In the unlikely case that the kernel is configured with CONFIG_MODULES=y and CONFIG_SYSFS=n, this results in a memory leak of charp values when a module is unloaded. Fix this issue by making destroy_params() always available when CONFIG_MODULES=y. Rename the function to module_destroy_params() to clarify that it is intended for use by the module loader. Fixes: e180a6b7759a ("param: fix charp parameters set via sysfs") Signed-off-by: Petr Pavlu Signed-off-by: Sami Tolvanen Signed-off-by: Sasha Levin --- include/linux/moduleparam.h | 11 +++-------- kernel/module.c | 4 ++-- kernel/params.c | 27 ++++++++++++++++++--------- 3 files changed, 23 insertions(+), 19 deletions(-) diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index 061e19c94a6bc..f73ca4d62683b 100644 --- a/include/linux/moduleparam.h +++ b/include/linux/moduleparam.h @@ -392,14 +392,9 @@ extern char *parse_args(const char *name, const char *doing, void *arg)); /* Called by module remove. */ -#ifdef CONFIG_SYSFS -extern void destroy_params(const struct kernel_param *params, unsigned num); -#else -static inline void destroy_params(const struct kernel_param *params, - unsigned num) -{ -} -#endif /* !CONFIG_SYSFS */ +#ifdef CONFIG_MODULES +void module_destroy_params(const struct kernel_param *params, unsigned int num); +#endif /* All the helper functions */ /* The macros to do compile-time type checking stolen from Jakub diff --git a/kernel/module.c b/kernel/module.c index 07fa34461fa2f..b6409b0032b85 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2179,7 +2179,7 @@ static void free_module(struct module *mod) module_unload_free(mod); /* Free any allocated parameters. */ - destroy_params(mod->kp, mod->num_kp); + module_destroy_params(mod->kp, mod->num_kp); if (is_livepatch_module(mod)) free_module_elf(mod); @@ -4166,7 +4166,7 @@ static int load_module(struct load_info *info, const char __user *uargs, mod_sysfs_teardown(mod); coming_cleanup: mod->state = MODULE_STATE_GOING; - destroy_params(mod->kp, mod->num_kp); + module_destroy_params(mod->kp, mod->num_kp); blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_GOING, mod); klp_module_going(mod); diff --git a/kernel/params.c b/kernel/params.c index 9a76f556b898a..1233673b42ecc 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -743,15 +743,6 @@ void module_param_sysfs_remove(struct module *mod) } #endif -void destroy_params(const struct kernel_param *params, unsigned num) -{ - unsigned int i; - - for (i = 0; i < num; i++) - if (params[i].ops->free) - params[i].ops->free(params[i].arg); -} - struct module_kobject * __init_or_module lookup_or_create_module_kobject(const char *name) { @@ -971,3 +962,21 @@ static int __init param_sysfs_init(void) subsys_initcall(param_sysfs_init); #endif /* CONFIG_SYSFS */ + +#ifdef CONFIG_MODULES + +/* + * module_destroy_params - free all parameters for one module + * @params: module parameters (array) + * @num: number of module parameters + */ +void module_destroy_params(const struct kernel_param *params, unsigned int num) +{ + unsigned int i; + + for (i = 0; i < num; i++) + if (params[i].ops->free) + params[i].ops->free(params[i].arg); +} + +#endif /* CONFIG_MODULES */ -- 2.53.0