diff options
Diffstat (limited to 'arch/arm/mm/fault.c')
| -rw-r--r-- | arch/arm/mm/fault.c | 59 |
1 files changed, 45 insertions, 14 deletions
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 92f5801..23b0b03 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -393,6 +393,9 @@ do_translation_fault(unsigned long addr, unsigned int fsr, if (addr < TASK_SIZE) return do_page_fault(addr, fsr, regs); + if (user_mode(regs)) + goto bad_area; + index = pgd_index(addr); /* @@ -410,7 +413,16 @@ do_translation_fault(unsigned long addr, unsigned int fsr, pmd_k = pmd_offset(pgd_k, addr); pmd = pmd_offset(pgd, addr); - if (pmd_none(*pmd_k)) + /* + * On ARM one Linux PGD entry contains two hardware entries (see page + * tables layout in pgtable.h). We normally guarantee that we always + * fill both L1 entries. But create_mapping() doesn't follow the rule. + * It can create inidividual L1 entries, so here we have to call + * pmd_none() check for the entry really corresponded to address, not + * for the first of pair. + */ + index = (addr >> SECTION_SHIFT) & 1; + if (pmd_none(pmd_k[index])) goto bad_area; copy_pmd(pmd, pmd_k); @@ -460,15 +472,10 @@ static struct fsr_info { * defines these to be "precise" aborts. */ { do_bad, SIGSEGV, 0, "vector exception" }, - { do_bad, SIGILL, BUS_ADRALN, "alignment exception" }, + { do_bad, SIGBUS, BUS_ADRALN, "alignment exception" }, { do_bad, SIGKILL, 0, "terminal exception" }, - { do_bad, SIGILL, BUS_ADRALN, "alignment exception" }, -/* Do we need runtime check ? */ -#if __LINUX_ARM_ARCH__ < 6 + { do_bad, SIGBUS, BUS_ADRALN, "alignment exception" }, { do_bad, SIGBUS, 0, "external abort on linefetch" }, -#else - { do_translation_fault, SIGSEGV, SEGV_MAPERR, "I-cache maintenance fault" }, -#endif { do_translation_fault, SIGSEGV, SEGV_MAPERR, "section translation fault" }, { do_bad, SIGBUS, 0, "external abort on linefetch" }, { do_page_fault, SIGSEGV, SEGV_MAPERR, "page translation fault" }, @@ -505,13 +512,15 @@ static struct fsr_info { void __init hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *), - int sig, const char *name) + int sig, int code, const char *name) { - if (nr >= 0 && nr < ARRAY_SIZE(fsr_info)) { - fsr_info[nr].fn = fn; - fsr_info[nr].sig = sig; - fsr_info[nr].name = name; - } + if (nr < 0 || nr >= ARRAY_SIZE(fsr_info)) + BUG(); + + fsr_info[nr].fn = fn; + fsr_info[nr].sig = sig; + fsr_info[nr].code = code; + fsr_info[nr].name = name; } /* @@ -591,3 +600,25 @@ do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs) arm_notify_die("", regs, &info, ifsr, 0); } +static int __init exceptions_init(void) +{ + if (cpu_architecture() >= CPU_ARCH_ARMv6) { + hook_fault_code(4, do_translation_fault, SIGSEGV, SEGV_MAPERR, + "I-cache maintenance fault"); + } + + if (cpu_architecture() >= CPU_ARCH_ARMv7) { + /* + * TODO: Access flag faults introduced in ARMv6K. + * Runtime check for 'K' extension is needed + */ + hook_fault_code(3, do_bad, SIGSEGV, SEGV_MAPERR, + "section access flag fault"); + hook_fault_code(6, do_bad, SIGSEGV, SEGV_MAPERR, + "section access flag fault"); + } + + return 0; +} + +arch_initcall(exceptions_init); |
