[PATCH v6 01/33] mm: Introduce ARCH_HAS_USER_SHADOW_STACK
From: Deepak Gupta <hidden>
Date: 2024-10-08 22:37:50
Also in:
linux-arch, linux-devicetree, linux-fsdevel, linux-kselftest, linux-mm, linux-riscv, lkml
Subsystem:
filesystems (vfs and infrastructure), memory management, memory management - core, memory mapping, proc filesystem, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Alexander Viro, Christian Brauner, Andrew Morton, David Hildenbrand, Liam R. Howlett, Lorenzo Stoakes, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Mark Brown <broonie@kernel.org> Since multiple architectures have support for shadow stacks and we need to select support for this feature in several places in the generic code provide a generic config option that the architectures can select. Suggested-by: David Hildenbrand <redacted> Acked-by: David Hildenbrand <redacted> Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Reviewed-by: Deepak Gupta <redacted> Reviewed-by: Carlos Bilbao <redacted> --- arch/x86/Kconfig | 1 + fs/proc/task_mmu.c | 2 +- include/linux/mm.h | 2 +- mm/Kconfig | 6 ++++++ 4 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2852fcd82cbd..8ccae77d40f7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig@@ -1954,6 +1954,7 @@ config X86_USER_SHADOW_STACK depends on AS_WRUSS depends on X86_64 select ARCH_USES_HIGH_VMA_FLAGS + select ARCH_HAS_USER_SHADOW_STACK select X86_CET help Shadow stack protection is a hardware feature that detects function
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 72f14fd59c2d..23f875e78eae 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c@@ -971,7 +971,7 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR [ilog2(VM_UFFD_MINOR)] = "ui", #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ -#ifdef CONFIG_X86_USER_SHADOW_STACK +#ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK [ilog2(VM_SHADOW_STACK)] = "ss", #endif #if defined(CONFIG_64BIT) || defined(CONFIG_PPC32)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index ecf63d2b0582..57533b9cae95 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h@@ -354,7 +354,7 @@ extern unsigned int kobjsize(const void *objp); #endif #endif /* CONFIG_ARCH_HAS_PKEYS */ -#ifdef CONFIG_X86_USER_SHADOW_STACK +#ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK /* * VM_SHADOW_STACK should not be set with VM_SHARED because of lack of * support core mm.
diff --git a/mm/Kconfig b/mm/Kconfig
index 4c9f5ea13271..4b2a1ef9a161 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig@@ -1296,6 +1296,12 @@ config NUMA_EMU into virtual nodes when booted with "numa=fake=N", where N is the number of nodes. This is only useful for debugging. +config ARCH_HAS_USER_SHADOW_STACK + bool + help + The architecture has hardware support for userspace shadow call + stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss). + source "mm/damon/Kconfig" endmenu
--
2.45.0