kprobes/x86: Fix to add __kprobes to in-kernel fault handing functions

Add __kprobes to the functions which handle in-kernel fixable page
faults. Since kprobes can cause those in-kernel page faults by accessing
kprobe data structures, probing those fault functions will cause
fault-int3-loop (do_page_fault has already been marked as __kprobes).

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20090827172311.8246.92725.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index bfae139..c322e59 100644 (file)
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -38,7 +38,8 @@ enum x86_pf_error_code {
  * Returns 0 if mmiotrace is disabled, or if the fault is not
  * handled by mmiotrace:
  */
  * Returns 0 if mmiotrace is disabled, or if the fault is not
  * handled by mmiotrace:
  */

-static inline int kmmio_fault(struct pt_regs *regs, unsigned long addr)
+static inline int __kprobes
+kmmio_fault(struct pt_regs *regs, unsigned long addr)

 {
        if (unlikely(is_kmmio_active()))
                if (kmmio_handler(regs, addr) == 1)
 {
        if (unlikely(is_kmmio_active()))
                if (kmmio_handler(regs, addr) == 1)


@@ -46,7 +47,7 @@ static inline int kmmio_fault(struct pt_regs *regs, unsigned long addr)
        return 0;
 }
 
        return 0;
 }
 

-static inline int notify_page_fault(struct pt_regs *regs)
+static inline int __kprobes notify_page_fault(struct pt_regs *regs)

 {
        int ret = 0;
 
 {
        int ret = 0;
 


@@ -239,7 +240,7 @@ void vmalloc_sync_all(void)
  *
  *   Handle a fault on the vmalloc or module mapping area
  */
  *
  *   Handle a fault on the vmalloc or module mapping area
  */

-static noinline int vmalloc_fault(unsigned long address)
+static noinline __kprobes int vmalloc_fault(unsigned long address)

 {
        unsigned long pgd_paddr;
        pmd_t *pmd_k;
 {
        unsigned long pgd_paddr;
        pmd_t *pmd_k;


@@ -361,7 +362,7 @@ void vmalloc_sync_all(void)
  *
  * This assumes no large pages in there.
  */
  *
  * This assumes no large pages in there.
  */

-static noinline int vmalloc_fault(unsigned long address)
+static noinline __kprobes int vmalloc_fault(unsigned long address)

 {
        pgd_t *pgd, *pgd_ref;
        pud_t *pud, *pud_ref;
 {
        pgd_t *pgd, *pgd_ref;
        pud_t *pud, *pud_ref;


@@ -858,7 +859,7 @@ static int spurious_fault_check(unsigned long error_code, pte_t *pte)
  * There are no security implications to leaving a stale TLB when
  * increasing the permissions on a page.
  */
  * There are no security implications to leaving a stale TLB when
  * increasing the permissions on a page.
  */

-static noinline int
+static noinline __kprobes int

 spurious_fault(unsigned long error_code, unsigned long address)
 {
        pgd_t *pgd;
 spurious_fault(unsigned long error_code, unsigned long address)
 {
        pgd_t *pgd;