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-rw-r--r--arch/x86/entry/calling.h4
-rw-r--r--arch/x86/entry/entry.S17
-rw-r--r--arch/x86/entry/entry_64.S20
-rw-r--r--arch/x86/entry/syscalls/syscall_32.tbl2
-rw-r--r--arch/x86/entry/syscalls/syscall_64.tbl2
-rw-r--r--arch/x86/entry/vdso/Makefile3
-rw-r--r--arch/x86/entry/vdso/vma.c40
-rw-r--r--arch/x86/entry/vsyscall/vsyscall_64.c2
8 files changed, 49 insertions, 41 deletions
diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h
index d83236b96f22..94519688b007 100644
--- a/arch/x86/entry/calling.h
+++ b/arch/x86/entry/calling.h
@@ -369,7 +369,7 @@ For 32-bit we have the following conventions - kernel is built with
.endm
.macro STACKLEAK_ERASE_NOCLOBBER
-#ifdef CONFIG_GCC_PLUGIN_STACKLEAK
+#ifdef CONFIG_KSTACK_ERASE
PUSH_AND_CLEAR_REGS
call stackleak_erase
POP_REGS
@@ -388,7 +388,7 @@ For 32-bit we have the following conventions - kernel is built with
#endif /* !CONFIG_X86_64 */
.macro STACKLEAK_ERASE
-#ifdef CONFIG_GCC_PLUGIN_STACKLEAK
+#ifdef CONFIG_KSTACK_ERASE
call stackleak_erase
#endif
.endm
diff --git a/arch/x86/entry/entry.S b/arch/x86/entry/entry.S
index d3caa31240ed..8e9a0cc20a4a 100644
--- a/arch/x86/entry/entry.S
+++ b/arch/x86/entry/entry.S
@@ -17,38 +17,39 @@
.pushsection .noinstr.text, "ax"
-SYM_FUNC_START(entry_ibpb)
+/* Clobbers AX, CX, DX */
+SYM_FUNC_START(write_ibpb)
ANNOTATE_NOENDBR
movl $MSR_IA32_PRED_CMD, %ecx
- movl $PRED_CMD_IBPB, %eax
+ movl _ASM_RIP(x86_pred_cmd), %eax
xorl %edx, %edx
wrmsr
/* Make sure IBPB clears return stack preductions too. */
FILL_RETURN_BUFFER %rax, RSB_CLEAR_LOOPS, X86_BUG_IBPB_NO_RET
RET
-SYM_FUNC_END(entry_ibpb)
+SYM_FUNC_END(write_ibpb)
/* For KVM */
-EXPORT_SYMBOL_GPL(entry_ibpb);
+EXPORT_SYMBOL_GPL(write_ibpb);
.popsection
/*
* Define the VERW operand that is disguised as entry code so that
- * it can be referenced with KPTI enabled. This ensure VERW can be
+ * it can be referenced with KPTI enabled. This ensures VERW can be
* used late in exit-to-user path after page tables are switched.
*/
.pushsection .entry.text, "ax"
.align L1_CACHE_BYTES, 0xcc
-SYM_CODE_START_NOALIGN(mds_verw_sel)
+SYM_CODE_START_NOALIGN(x86_verw_sel)
UNWIND_HINT_UNDEFINED
ANNOTATE_NOENDBR
.word __KERNEL_DS
.align L1_CACHE_BYTES, 0xcc
-SYM_CODE_END(mds_verw_sel);
+SYM_CODE_END(x86_verw_sel);
/* For KVM */
-EXPORT_SYMBOL_GPL(mds_verw_sel);
+EXPORT_SYMBOL_GPL(x86_verw_sel);
.popsection
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index f40bdf97d390..ed04a968cc7d 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1525,7 +1525,9 @@ SYM_CODE_END(rewind_stack_and_make_dead)
* ORC to unwind properly.
*
* The alignment is for performance and not for safety, and may be safely
- * refactored in the future if needed.
+ * refactored in the future if needed. The .skips are for safety, to ensure
+ * that all RETs are in the second half of a cacheline to mitigate Indirect
+ * Target Selection, rather than taking the slowpath via its_return_thunk.
*/
SYM_FUNC_START(clear_bhb_loop)
ANNOTATE_NOENDBR
@@ -1536,10 +1538,22 @@ SYM_FUNC_START(clear_bhb_loop)
call 1f
jmp 5f
.align 64, 0xcc
+ /*
+ * Shift instructions so that the RET is in the upper half of the
+ * cacheline and don't take the slowpath to its_return_thunk.
+ */
+ .skip 32 - (.Lret1 - 1f), 0xcc
ANNOTATE_INTRA_FUNCTION_CALL
1: call 2f
- RET
+.Lret1: RET
.align 64, 0xcc
+ /*
+ * As above shift instructions for RET at .Lret2 as well.
+ *
+ * This should be ideally be: .skip 32 - (.Lret2 - 2f), 0xcc
+ * but some Clang versions (e.g. 18) don't like this.
+ */
+ .skip 32 - 18, 0xcc
2: movl $5, %eax
3: jmp 4f
nop
@@ -1547,7 +1561,7 @@ SYM_FUNC_START(clear_bhb_loop)
jnz 3b
sub $1, %ecx
jnz 1b
- RET
+.Lret2: RET
5: lfence
pop %rbp
RET
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index ac007ea00979..4877e16da69a 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -473,3 +473,5 @@
465 i386 listxattrat sys_listxattrat
466 i386 removexattrat sys_removexattrat
467 i386 open_tree_attr sys_open_tree_attr
+468 i386 file_getattr sys_file_getattr
+469 i386 file_setattr sys_file_setattr
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index cfb5ca41e30d..92cf0fe2291e 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -391,6 +391,8 @@
465 common listxattrat sys_listxattrat
466 common removexattrat sys_removexattrat
467 common open_tree_attr sys_open_tree_attr
+468 common file_getattr sys_file_getattr
+469 common file_setattr sys_file_setattr
#
# Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index 54d3e9774d62..f247f5f5cb44 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -62,7 +62,7 @@ ifneq ($(RETPOLINE_VDSO_CFLAGS),)
endif
endif
-$(vobjs): KBUILD_CFLAGS := $(filter-out $(PADDING_CFLAGS) $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL)
+$(vobjs): KBUILD_CFLAGS := $(filter-out $(PADDING_CFLAGS) $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) $(RANDSTRUCT_CFLAGS) $(KSTACK_ERASE_CFLAGS) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL)
$(vobjs): KBUILD_AFLAGS += -DBUILD_VDSO
#
@@ -123,6 +123,7 @@ KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32))
KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32))
KBUILD_CFLAGS_32 := $(filter-out $(RANDSTRUCT_CFLAGS),$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 := $(filter-out $(KSTACK_ERASE_CFLAGS),$(KBUILD_CFLAGS_32))
KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32))
KBUILD_CFLAGS_32 := $(filter-out $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS_32))
KBUILD_CFLAGS_32 := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS_32))
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 9518bf1ddf35..afe105b2f907 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -65,7 +65,6 @@ static vm_fault_t vdso_fault(const struct vm_special_mapping *sm,
static void vdso_fix_landing(const struct vdso_image *image,
struct vm_area_struct *new_vma)
{
-#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
if (in_ia32_syscall() && image == &vdso_image_32) {
struct pt_regs *regs = current_pt_regs();
unsigned long vdso_land = image->sym_int80_landing_pad;
@@ -76,7 +75,6 @@ static void vdso_fix_landing(const struct vdso_image *image,
if (regs->ip == old_land_addr)
regs->ip = new_vma->vm_start + vdso_land;
}
-#endif
}
static int vdso_mremap(const struct vm_special_mapping *sm,
@@ -162,7 +160,8 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
text_start,
image->size,
VM_READ|VM_EXEC|
- VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
+ VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
+ VM_SEALED_SYSMAP,
&vdso_mapping);
if (IS_ERR(vma)) {
@@ -181,7 +180,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
VDSO_VCLOCK_PAGES_START(addr),
VDSO_NR_VCLOCK_PAGES * PAGE_SIZE,
VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
- VM_PFNMAP,
+ VM_PFNMAP|VM_SEALED_SYSMAP,
&vvar_vclock_mapping);
if (IS_ERR(vma)) {
@@ -226,7 +225,6 @@ int map_vdso_once(const struct vdso_image *image, unsigned long addr)
return map_vdso(image, addr);
}
-#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
static int load_vdso32(void)
{
if (vdso32_enabled != 1) /* Other values all mean "disabled" */
@@ -234,45 +232,38 @@ static int load_vdso32(void)
return map_vdso(&vdso_image_32, 0);
}
-#endif
-#ifdef CONFIG_X86_64
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
{
- if (!vdso64_enabled)
- return 0;
+ if (IS_ENABLED(CONFIG_X86_64)) {
+ if (!vdso64_enabled)
+ return 0;
+
+ return map_vdso(&vdso_image_64, 0);
+ }
- return map_vdso(&vdso_image_64, 0);
+ return load_vdso32();
}
#ifdef CONFIG_COMPAT
int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
int uses_interp, bool x32)
{
-#ifdef CONFIG_X86_X32_ABI
- if (x32) {
+ if (IS_ENABLED(CONFIG_X86_X32_ABI) && x32) {
if (!vdso64_enabled)
return 0;
return map_vdso(&vdso_image_x32, 0);
}
-#endif
-#ifdef CONFIG_IA32_EMULATION
- return load_vdso32();
-#else
+
+ if (IS_ENABLED(CONFIG_IA32_EMULATION))
+ return load_vdso32();
+
return 0;
-#endif
-}
-#endif
-#else
-int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
-{
- return load_vdso32();
}
#endif
bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs)
{
-#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
const struct vdso_image *image = current->mm->context.vdso_image;
unsigned long vdso = (unsigned long) current->mm->context.vdso;
@@ -281,7 +272,6 @@ bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs)
regs->ip == vdso + image->sym_vdso32_rt_sigreturn_landing_pad)
return true;
}
-#endif
return false;
}
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c
index 2fb7d53cf333..c9103a6fa06e 100644
--- a/arch/x86/entry/vsyscall/vsyscall_64.c
+++ b/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -341,9 +341,7 @@ void __init set_vsyscall_pgtable_user_bits(pgd_t *root)
pgd = pgd_offset_pgd(root, VSYSCALL_ADDR);
set_pgd(pgd, __pgd(pgd_val(*pgd) | _PAGE_USER));
p4d = p4d_offset(pgd, VSYSCALL_ADDR);
-#if CONFIG_PGTABLE_LEVELS >= 5
set_p4d(p4d, __p4d(p4d_val(*p4d) | _PAGE_USER));
-#endif
pud = pud_offset(p4d, VSYSCALL_ADDR);
set_pud(pud, __pud(pud_val(*pud) | _PAGE_USER));
pmd = pmd_offset(pud, VSYSCALL_ADDR);
generated by cgit (git 2.34.1) at 2025-08-06 00:43:20 +0000