kgdb: don't needlessly skip PAGE_USER test for Fsl booke

The bypassing of this test is a leftover from 2.4 vintage
kernels, and is no longer appropriate, or even used by KGDB.
Currently KGDB uses probe_kernel_write() for all access to
memory via the KGDB core, so it can simply be deleted.

This fixes CVE-2010-1446.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Wufei <fei.wu@windriver.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

diff --git a/arch/powerpc/mm/fsl_booke_mmu.c b/arch/powerpc/mm/fsl_booke_mmu.c
index c539472..1ce9dd5 100644 (file)
--- a/arch/powerpc/mm/fsl_booke_mmu.c
+++ b/arch/powerpc/mm/fsl_booke_mmu.c
@@ -155,15 +155,10 @@ static void settlbcam(int index, unsigned long virt, phys_addr_t phys,
        if (cur_cpu_spec->cpu_features & MMU_FTR_BIG_PHYS)
                TLBCAM[index].MAS7 = (u64)phys >> 32;
 
        if (cur_cpu_spec->cpu_features & MMU_FTR_BIG_PHYS)
                TLBCAM[index].MAS7 = (u64)phys >> 32;
 

-#ifndef CONFIG_KGDB /* want user access for breakpoints */

        if (flags & _PAGE_USER) {
           TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR;
           TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0);
        }
        if (flags & _PAGE_USER) {
           TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR;
           TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0);
        }

-#else
-       TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR;
-       TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0);
-#endif

 
        tlbcam_addrs[index].start = virt;
        tlbcam_addrs[index].limit = virt + size - 1;
 
        tlbcam_addrs[index].start = virt;
        tlbcam_addrs[index].limit = virt + size - 1;