On 8/24/26 3:47 AM, Hao Ge wrote:
> If codetag_load_module() fails, err is never set and load_module()
> returns 0 after the module has been torn down.
> 
> Fixes: 044d2aee6c57 ("alloc_tag: handle module codetag load errors as module 
> load failures")
> Reported-by: Sashiko <[email protected]>
> Cc: [email protected]
> Signed-off-by: Hao Ge <[email protected]>
> ---
>  kernel/module/main.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/module/main.c b/kernel/module/main.c
> index 46dd8d25a605..afb810f0154c 100644
> --- a/kernel/module/main.c
> +++ b/kernel/module/main.c
> @@ -3568,7 +3568,8 @@ static int load_module(struct load_info *info, const 
> char __user *uargs,
>                       goto sysfs_cleanup;
>       }
>  
> -     if (codetag_load_module(mod))
> +     err = codetag_load_module(mod);
> +     if (err)
>               goto sysfs_cleanup;
>  
>       /* Get rid of temporary copy. */

This looks ok to me but there appears another bug related to this code
that would be good to fix at the same time. If the module is
a livepatch, the preceding call to copy_module_elf() allocates
mod->klp_info. However, if codetag_load_module() fails, the code doesn't
free it.

I think we want something like this (not tested):

diff --git a/kernel/module/main.c b/kernel/module/main.c
index d0e1e0bd2ad0..c1b34dc1e89a 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -3581,8 +3581,9 @@ static int load_module(struct load_info *info, const char 
__user *uargs,
                        goto sysfs_cleanup;
        }
 
-       if (codetag_load_module(mod))
-               goto sysfs_cleanup;
+       err = codetag_load_module(mod);
+       if (err)
+               goto livepatch_cleanup;
 
        /* Get rid of temporary copy. */
        free_copy(info, flags);
@@ -3592,6 +3593,9 @@ static int load_module(struct load_info *info, const char 
__user *uargs,
 
        return do_init_module(mod);
 
+ livepatch_cleanup:
+       if (is_livepatch_module(mod))
+               free_module_elf(mod);
  sysfs_cleanup:
        mod_sysfs_teardown(mod);
  coming_cleanup:

-- 
Thanks,
Petr

Reply via email to