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-rw-r--r--arch/x86/kernel/entry_32.S100
1 files changed, 78 insertions, 22 deletions
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index c097e7d607c6..44a8e0dc6737 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -334,6 +334,10 @@ ENTRY(ret_from_fork)
END(ret_from_fork)
/*
+ * Interrupt exit functions should be protected against kprobes
+ */
+ .pushsection .kprobes.text, "ax"
+/*
* Return to user mode is not as complex as all this looks,
* but we want the default path for a system call return to
* go as quickly as possible which is why some of this is
@@ -383,6 +387,10 @@ need_resched:
END(resume_kernel)
#endif
CFI_ENDPROC
+/*
+ * End of kprobes section
+ */
+ .popsection
/* SYSENTER_RETURN points to after the "sysenter" instruction in
the vsyscall page. See vsyscall-sysentry.S, which defines the symbol. */
@@ -513,6 +521,10 @@ sysexit_audit:
PTGS_TO_GS_EX
ENDPROC(ia32_sysenter_target)
+/*
+ * syscall stub including irq exit should be protected against kprobes
+ */
+ .pushsection .kprobes.text, "ax"
# system call handler stub
ENTRY(system_call)
RING0_INT_FRAME # can't unwind into user space anyway
@@ -705,26 +717,69 @@ syscall_badsys:
jmp resume_userspace
END(syscall_badsys)
CFI_ENDPROC
+/*
+ * End of kprobes section
+ */
+ .popsection
/*
* System calls that need a pt_regs pointer.
*/
-#define PTREGSCALL(name) \
+#define PTREGSCALL0(name) \
ALIGN; \
ptregs_##name: \
leal 4(%esp),%eax; \
jmp sys_##name;
-PTREGSCALL(iopl)
-PTREGSCALL(fork)
-PTREGSCALL(clone)
-PTREGSCALL(vfork)
-PTREGSCALL(execve)
-PTREGSCALL(sigaltstack)
-PTREGSCALL(sigreturn)
-PTREGSCALL(rt_sigreturn)
-PTREGSCALL(vm86)
-PTREGSCALL(vm86old)
+#define PTREGSCALL1(name) \
+ ALIGN; \
+ptregs_##name: \
+ leal 4(%esp),%edx; \
+ movl (PT_EBX+4)(%esp),%eax; \
+ jmp sys_##name;
+
+#define PTREGSCALL2(name) \
+ ALIGN; \
+ptregs_##name: \
+ leal 4(%esp),%ecx; \
+ movl (PT_ECX+4)(%esp),%edx; \
+ movl (PT_EBX+4)(%esp),%eax; \
+ jmp sys_##name;
+
+#define PTREGSCALL3(name) \
+ ALIGN; \
+ptregs_##name: \
+ leal 4(%esp),%eax; \
+ pushl %eax; \
+ movl PT_EDX(%eax),%ecx; \
+ movl PT_ECX(%eax),%edx; \
+ movl PT_EBX(%eax),%eax; \
+ call sys_##name; \
+ addl $4,%esp; \
+ ret
+
+PTREGSCALL1(iopl)
+PTREGSCALL0(fork)
+PTREGSCALL0(vfork)
+PTREGSCALL3(execve)
+PTREGSCALL2(sigaltstack)
+PTREGSCALL0(sigreturn)
+PTREGSCALL0(rt_sigreturn)
+PTREGSCALL2(vm86)
+PTREGSCALL1(vm86old)
+
+/* Clone is an oddball. The 4th arg is in %edi */
+ ALIGN;
+ptregs_clone:
+ leal 4(%esp),%eax
+ pushl %eax
+ pushl PT_EDI(%eax)
+ movl PT_EDX(%eax),%ecx
+ movl PT_ECX(%eax),%edx
+ movl PT_EBX(%eax),%eax
+ call sys_clone
+ addl $8,%esp
+ ret
.macro FIXUP_ESPFIX_STACK
/*
@@ -814,6 +869,10 @@ common_interrupt:
ENDPROC(common_interrupt)
CFI_ENDPROC
+/*
+ * Irq entries should be protected against kprobes
+ */
+ .pushsection .kprobes.text, "ax"
#define BUILD_INTERRUPT3(name, nr, fn) \
ENTRY(name) \
RING0_INT_FRAME; \
@@ -980,16 +1039,16 @@ ENTRY(spurious_interrupt_bug)
jmp error_code
CFI_ENDPROC
END(spurious_interrupt_bug)
+/*
+ * End of kprobes section
+ */
+ .popsection
ENTRY(kernel_thread_helper)
pushl $0 # fake return address for unwinder
CFI_STARTPROC
- movl %edx,%eax
- push %edx
- CFI_ADJUST_CFA_OFFSET 4
- call *%ebx
- push %eax
- CFI_ADJUST_CFA_OFFSET 4
+ movl %edi,%eax
+ call *%esi
call do_exit
ud2 # padding for call trace
CFI_ENDPROC
@@ -1185,17 +1244,14 @@ END(ftrace_graph_caller)
.globl return_to_handler
return_to_handler:
- pushl $0
pushl %eax
- pushl %ecx
pushl %edx
movl %ebp, %eax
call ftrace_return_to_handler
- movl %eax, 0xc(%esp)
+ movl %eax, %ecx
popl %edx
- popl %ecx
popl %eax
- ret
+ jmp *%ecx
#endif
.section .rodata,"a"
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