From 3a6455d56bd7c4cfb1ea35ddae052943065e338e Mon Sep 17 00:00:00 2001 From: "Lorenzo Stoakes (Oracle)" Date: Fri, 20 Mar 2026 19:38:34 +0000 Subject: mm: convert do_brk_flags() to use vma_flags_t In order to be able to do this, we need to change VM_DATA_DEFAULT_FLAGS and friends and update the architecture-specific definitions also. We then have to update some KSM logic to handle VMA flags, and introduce VMA_STACK_FLAGS to define the vma_flags_t equivalent of VM_STACK_FLAGS. We also introduce two helper functions for use during the time we are converting legacy flags to vma_flags_t values - vma_flags_to_legacy() and legacy_to_vma_flags(). This enables us to iteratively make changes to break these changes up into separate parts. We use these explicitly here to keep VM_STACK_FLAGS around for certain users which need to maintain the legacy vm_flags_t values for the time being. We are no longer able to rely on the simple VM_xxx being set to zero if the feature is not enabled, so in the case of VM_DROPPABLE we introduce VMA_DROPPABLE as the vma_flags_t equivalent, which is set to EMPTY_VMA_FLAGS if the droppable flag is not available. While we're here, we make the description of do_brk_flags() into a kdoc comment, as it almost was already. We use vma_flags_to_legacy() to not need to update the vm_get_page_prot() logic as this time. Note that in create_init_stack_vma() we have to replace the BUILD_BUG_ON() with a VM_WARN_ON_ONCE() as the tested values are no longer build time available. We also update mprotect_fixup() to use VMA flags where possible, though we have to live with a little duplication between vm_flags_t and vma_flags_t values for the time being until further conversions are made. While we're here, update VM_SPECIAL to be defined in terms of VMA_SPECIAL_FLAGS now we have vma_flags_to_legacy(). Finally, we update the VMA tests to reflect these changes. Link: https://lkml.kernel.org/r/d02e3e45d9a33d7904b149f5604904089fd640ae.1774034900.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) Acked-by: Paul Moore [SELinux] Acked-by: Vlastimil Babka (SUSE) Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Al Viro Cc: Anton Ivanov Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chengming Zhou Cc: Christian Borntraeger Cc: Christian Brauner Cc: David Hildenbrand Cc: Dinh Nguyen Cc: Heiko Carstens Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Jan Kara Cc: Jann Horn Cc: Johannes Berg Cc: Kees Cook Cc: Liam Howlett Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Michal Hocko Cc: Mike Rapoport Cc: Nicholas Piggin Cc: Ondrej Mosnacek Cc: Palmer Dabbelt Cc: Pedro Falcato Cc: Richard Weinberger Cc: Russell King Cc: Stephen Smalley Cc: Suren Baghdasaryan Cc: Sven Schnelle Cc: Thomas Bogendoerfer Cc: Vasily Gorbik Cc: Vineet Gupta Cc: WANG Xuerui Cc: Will Deacon Cc: xu xin Signed-off-by: Andrew Morton --- security/selinux/hooks.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'security') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index d8224ea113d1..903303e084c2 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -7713,6 +7713,8 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = { static __init int selinux_init(void) { + vma_flags_t data_default_flags = VMA_DATA_DEFAULT_FLAGS; + pr_info("SELinux: Initializing.\n"); memset(&selinux_state, 0, sizeof(selinux_state)); @@ -7729,7 +7731,7 @@ static __init int selinux_init(void) AUDIT_CFG_LSM_SECCTX_SUBJECT | AUDIT_CFG_LSM_SECCTX_OBJECT); - default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); + default_noexec = !vma_flags_test(&data_default_flags, VMA_EXEC_BIT); if (!default_noexec) pr_notice("SELinux: virtual memory is executable by default\n"); -- cgit v1.2.3