> On 9 Sep 2025, at 12:25 PM, Srish Srinivasan <[email protected]> wrote: > > Many modules call grub_unregister_{command(), extcmd()} from > GRUB_MOD_FINI() without checking for a failure in registration. > This could lead to a NULL pointer dereference in unregistration. > > Perform explicit NULL check in both the unregister helpers. > > Signed-off-by: Srish Srinivasan <[email protected]>
Reviewed-by: Sudhakar Kuppusamy <[email protected]> > --- > grub-core/commands/extcmd.c | 3 +++ > grub-core/kern/command.c | 3 +++ > 2 files changed, 6 insertions(+) > > diff --git a/grub-core/commands/extcmd.c b/grub-core/commands/extcmd.c > index c236be13a..7f8cb3f67 100644 > --- a/grub-core/commands/extcmd.c > +++ b/grub-core/commands/extcmd.c > @@ -139,6 +139,9 @@ grub_register_extcmd_lockdown (const char *name, > grub_extcmd_func_t func, > void > grub_unregister_extcmd (grub_extcmd_t ext) > { > + if (ext == NULL) > + return; > + > grub_unregister_command (ext->cmd); > grub_free (ext); > } > diff --git a/grub-core/kern/command.c b/grub-core/kern/command.c > index 5812e131c..a1b4c81a9 100644 > --- a/grub-core/kern/command.c > +++ b/grub-core/kern/command.c > @@ -104,6 +104,9 @@ grub_register_command_lockdown (const char *name, > void > grub_unregister_command (grub_command_t cmd) > { > + if (cmd == NULL) > + return; > + > if ((cmd->prio & GRUB_COMMAND_FLAG_ACTIVE) && (cmd->next)) > cmd->next->prio |= GRUB_COMMAND_FLAG_ACTIVE; > grub_list_remove (GRUB_AS_LIST (cmd)); > -- > 2.51.0 > _______________________________________________ Grub-devel mailing list [email protected] https://lists.gnu.org/mailman/listinfo/grub-devel
