diff options
| author | Petr Pavlu <petr.pavlu@suse.com> | 2026-03-13 14:48:02 +0100 |
|---|---|---|
| committer | Sami Tolvanen <samitolvanen@google.com> | 2026-03-18 21:43:18 +0000 |
| commit | deffe1edba626d474fef38007c03646ca5876a0e (patch) | |
| tree | 113de16495393340dc12e1891e4b5c181644ead1 /kernel | |
| parent | 4afc71bba8b7d7841681e7647ae02f5079aaf28f (diff) | |
module: Fix freeing of charp module parameters when CONFIG_SYSFS=n
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 <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/module/main.c | 4 | ||||
| -rw-r--r-- | kernel/params.c | 27 |
2 files changed, 20 insertions, 11 deletions
diff --git a/kernel/module/main.c b/kernel/module/main.c index c3ce106c70af..ef2e2130972f 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -1408,7 +1408,7 @@ 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); @@ -3519,7 +3519,7 @@ 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 7188a12dbe86..c6a354d54213 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -745,15 +745,6 @@ 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) { @@ -985,3 +976,21 @@ static int __init param_sysfs_builtin_init(void) late_initcall(param_sysfs_builtin_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 */ |