Commit 0562b572 authored by Pasha Tatashin's avatar Pasha Tatashin Committed by Andrew Morton
Browse files

liveupdate: fix return value on session allocation failure 

When session allocation fails during deserialization, the global 'err'
variable was not updated before returning.  This caused subsequent calls
to luo_session_deserialize() to incorrectly report success.

Ensure 'err' is set to the error code from PTR_ERR(session).  This ensures
that an error is correctly returned to userspace when it attempts to open
/dev/liveupdate in the new kernel if deserialization failed.

Link: https://lore.kernel.org/20260415193738.515491-1-pasha.tatashin@soleen.com


Signed-off-by: default avatarPasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: default avatarPratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 60265506

kernel/liveupdate/luo_session.c

+10 −5
Original line number Diff line number Diff line
@@ -514,11 +514,12 @@ int luo_session_deserialize(void) 
{

	struct luo_session_header *sh = &luo_session_global.incoming;

	static bool is_deserialized;

	static int err;

	static int saved_err;

	int err;



	/* If has been deserialized, always return the same error code */

	if (is_deserialized)

		return err;

		return saved_err;



	is_deserialized = true;

	if (!sh->active)
@@ -547,7 +548,8 @@ int luo_session_deserialize(void) 
			pr_warn("Failed to allocate session [%.*s] during deserialization %pe\n",

				(int)sizeof(sh->ser[i].name),

				sh->ser[i].name, session);

			return PTR_ERR(session);

			err = PTR_ERR(session);

			goto save_err;

		}



		err = luo_session_insert(sh, session);
@@ -555,7 +557,7 @@ int luo_session_deserialize(void) 
			pr_warn("Failed to insert session [%s] %pe\n",

				session->name, ERR_PTR(err));

			luo_session_free(session);

			return err;

			goto save_err;

		}



		scoped_guard(mutex, &session->mutex) {
@@ -565,7 +567,7 @@ int luo_session_deserialize(void) 
		if (err) {

			pr_warn("Failed to deserialize files for session [%s] %pe\n",

				session->name, ERR_PTR(err));

			return err;

			goto save_err;

		}

	}
@@ -574,6 +576,9 @@ int luo_session_deserialize(void) 
	sh->ser = NULL;



	return 0;

save_err:

	saved_err = err;

	return err;

}



int luo_session_serialize(void)