Le 27/06/2022 à 18:40, Aaron Tomlin a écrit :
> For diagnostic purposes, this patch, in addition to keeping a record/or
> track of the last known unloaded module, we now will include the
> module's taint flag(s) too e.g: " [last unloaded: fpga_mgr_mod(OE)]"
>
> Signed-off-by: Aaron Tomlin <atomlin@xxxxxxxxxx>
> ---
> kernel/module/main.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/module/main.c b/kernel/module/main.c
> index dcb83cf18d84..0ca6fd38b903 100644
> --- a/kernel/module/main.c
> +++ b/kernel/module/main.c
> @@ -524,7 +524,12 @@ static struct module_attribute modinfo_##field = { \
> MODINFO_ATTR(version);
> MODINFO_ATTR(srcversion);
>
> -static char last_unloaded_module[MODULE_NAME_LEN+1];
> +/*
> + * Maximum number of characters written by module_flags()
> + * without a module's state information.
> + */
> +#define LAST_UNLOADED_MODULE_NAME_LEN (MODULE_NAME_LEN + MODULE_FLAGS_BUF_SIZE - 2 + 1)
> +static char last_unloaded_module[LAST_UNLOADED_MODULE_NAME_LEN];
>
> #ifdef CONFIG_MODULE_UNLOAD
>
> @@ -694,6 +699,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
> {
> struct module *mod;
> char name[MODULE_NAME_LEN];
> + char buf[LAST_UNLOADED_MODULE_NAME_LEN];
> int ret, forced = 0;
>
> if (!capable(CAP_SYS_MODULE) || modules_disabled)
> @@ -753,8 +759,8 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
>
> async_synchronize_full();
>
> - /* Store the name of the last unloaded module for diagnostic purposes */
> strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
> + strcat(last_unloaded_module, module_flags(mod, buf, false));
You replace a bounded string copy by an unbounded strict contat.
Should you use strlcat() instead ?
>
> free_module(mod);
> /* someone could wait for the module in add_unformed_module() */
