From 361dd63ed5f1103ff21e22408a142a7d40804527 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Mon, 28 Nov 2022 15:42:39 +0100 Subject: [PATCH] lsm: Clarify documentation of vm_enough_memory hook include/linux/lsm_hooks.h reports the result of the LSM infrastructure to the callers, not what LSMs should return to the LSM infrastructure. Clarify that and add that if all LSMs return a positive value __vm_enough_memory() will be called with cap_sys_admin set. If at least one LSM returns 0 or negative, it will be called with cap_sys_admin cleared. Signed-off-by: Roberto Sassu Signed-off-by: Paul Moore --- include/linux/lsm_hooks.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 2831efebde69..c35e260efd8c 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -1398,7 +1398,11 @@ * Check permissions for allocating a new virtual mapping. * @mm contains the mm struct it is being added to. * @pages contains the number of pages. - * Return 0 if permission is granted. + * Return 0 if permission is granted by the LSM infrastructure to the + * caller. If all LSMs return a positive value, __vm_enough_memory() will + * be called with cap_sys_admin set. If at least one LSM returns 0 or + * negative, __vm_enough_memory() will be called with cap_sys_admin + * cleared. * * @ismaclabel: * Check if the extended attribute specified by @name