diff options
author | Mike Rapoport <rppt@linux.ibm.com> | 2023-06-12 17:11:07 -0700 |
---|---|---|
committer | Dave Hansen <dave.hansen@linux.intel.com> | 2023-08-02 15:01:51 -0700 |
commit | 680ed2f15e70d079c8148589a3ce9426fc0ff914 (patch) | |
tree | c22c5326d8e7770ad97377f44714a005333f5147 /Documentation/arch/x86 | |
parent | 2fab02b25ae7cf5f714ab456b03d9a3fe5ae98c9 (diff) |
x86/shstk: Add ARCH_SHSTK_UNLOCK
Userspace loaders may lock features before a CRIU restore operation has
the chance to set them to whatever state is required by the process
being restored. Allow a way for CRIU to unlock features. Add it as an
arch_prctl() like the other shadow stack operations, but restrict it being
called by the ptrace arch_pctl() interface.
[Merged into recent API changes, added commit log and docs]
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-42-rick.p.edgecombe%40intel.com
Diffstat (limited to 'Documentation/arch/x86')
-rw-r--r-- | Documentation/arch/x86/shstk.rst | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/arch/x86/shstk.rst b/Documentation/arch/x86/shstk.rst index f09afa504ec0..f3553cc8c758 100644 --- a/Documentation/arch/x86/shstk.rst +++ b/Documentation/arch/x86/shstk.rst @@ -75,6 +75,10 @@ arch_prctl(ARCH_SHSTK_LOCK, unsigned long features) are ignored. The mask is ORed with the existing value. So any feature bits set here cannot be enabled or disabled afterwards. +arch_prctl(ARCH_SHSTK_UNLOCK, unsigned long features) + Unlock features. 'features' is a mask of all features to unlock. All + bits set are processed, unset bits are ignored. Only works via ptrace. + The return values are as follows. On success, return 0. On error, errno can be:: |