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authorIngo Molnar <mingo@elte.hu>2008-12-31 08:31:57 +0100
committerIngo Molnar <mingo@elte.hu>2008-12-31 08:31:57 +0100
commita9de18eb761f7c1c860964b2e5addc1a35c7e861 (patch)
tree886e75fdfd09690cd262ca69cb7f5d1d42b48602 /arch/x86/mm/fault.c
parentb2aaf8f74cdc84a9182f6cabf198b7763bcb9d40 (diff)
parent6a94cb73064c952255336cc57731904174b2c58f (diff)
Merge branch 'linus' into stackprotector
Conflicts: arch/x86/include/asm/pda.h kernel/fork.c
Diffstat (limited to 'arch/x86/mm/fault.c')
-rw-r--r--arch/x86/mm/fault.c60
1 files changed, 26 insertions, 34 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index d18ea136d8a6..4c056b5d6a95 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -54,7 +54,7 @@
static inline int kmmio_fault(struct pt_regs *regs, unsigned long addr)
{
-#ifdef CONFIG_MMIOTRACE_HOOKS
+#ifdef CONFIG_MMIOTRACE
if (unlikely(is_kmmio_active()))
if (kmmio_handler(regs, addr) == 1)
return -1;
@@ -394,7 +394,7 @@ static void show_fault_oops(struct pt_regs *regs, unsigned long error_code,
if (pte && pte_present(*pte) && !pte_exec(*pte))
printk(KERN_CRIT "kernel tried to execute "
"NX-protected page - exploit attempt? "
- "(uid: %d)\n", current->uid);
+ "(uid: %d)\n", current_uid());
}
#endif
@@ -414,6 +414,7 @@ static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs,
unsigned long error_code)
{
unsigned long flags = oops_begin();
+ int sig = SIGKILL;
struct task_struct *tsk;
printk(KERN_ALERT "%s: Corrupted page table at address %lx\n",
@@ -424,8 +425,8 @@ static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs,
tsk->thread.trap_no = 14;
tsk->thread.error_code = error_code;
if (__die("Bad pagetable", regs, error_code))
- regs = NULL;
- oops_end(flags, regs, SIGKILL);
+ sig = 0;
+ oops_end(flags, regs, sig);
}
#endif
@@ -593,6 +594,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
#ifdef CONFIG_X86_64
unsigned long flags;
+ int sig;
#endif
tsk = current;
@@ -643,24 +645,23 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
}
-#ifdef CONFIG_X86_32
- /* It's safe to allow irq's after cr2 has been saved and the vmalloc
- fault has been handled. */
- if (regs->flags & (X86_EFLAGS_IF | X86_VM_MASK))
- local_irq_enable();
-
/*
- * If we're in an interrupt, have no user context or are running in an
- * atomic region then we must not take the fault.
+ * It's safe to allow irq's after cr2 has been saved and the
+ * vmalloc fault has been handled.
+ *
+ * User-mode registers count as a user access even for any
+ * potential system fault or CPU buglet.
*/
- if (in_atomic() || !mm)
- goto bad_area_nosemaphore;
-#else /* CONFIG_X86_64 */
- if (likely(regs->flags & X86_EFLAGS_IF))
+ if (user_mode_vm(regs)) {
+ local_irq_enable();
+ error_code |= PF_USER;
+ } else if (regs->flags & X86_EFLAGS_IF)
local_irq_enable();
+#ifdef CONFIG_X86_64
if (unlikely(error_code & PF_RSVD))
pgtable_bad(address, regs, error_code);
+#endif
/*
* If we're in an interrupt, have no user context or are running in an
@@ -669,15 +670,9 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
if (unlikely(in_atomic() || !mm))
goto bad_area_nosemaphore;
- /*
- * User-mode registers count as a user access even for any
- * potential system fault or CPU buglet.
- */
- if (user_mode_vm(regs))
- error_code |= PF_USER;
again:
-#endif
- /* When running in the kernel we expect faults to occur only to
+ /*
+ * When running in the kernel we expect faults to occur only to
* addresses in user space. All other faults represent errors in the
* kernel and should generate an OOPS. Unfortunately, in the case of an
* erroneous fault occurring in a code path which already holds mmap_sem
@@ -740,9 +735,6 @@ good_area:
goto bad_area;
}
-#ifdef CONFIG_X86_32
-survive:
-#endif
/*
* If for any reason at all we couldn't handle the fault,
* make sure we exit gracefully rather than endlessly redo
@@ -866,11 +858,12 @@ no_context:
bust_spinlocks(0);
do_exit(SIGKILL);
#else
+ sig = SIGKILL;
if (__die("Oops", regs, error_code))
- regs = NULL;
+ sig = 0;
/* Executive summary in case the body of the oops scrolled away */
printk(KERN_EMERG "CR2: %016lx\n", address);
- oops_end(flags, regs, SIGKILL);
+ oops_end(flags, regs, sig);
#endif
/*
@@ -881,12 +874,11 @@ out_of_memory:
up_read(&mm->mmap_sem);
if (is_global_init(tsk)) {
yield();
-#ifdef CONFIG_X86_32
- down_read(&mm->mmap_sem);
- goto survive;
-#else
+ /*
+ * Re-lookup the vma - in theory the vma tree might
+ * have changed:
+ */
goto again;
-#endif
}
printk("VM: killing process %s\n", tsk->comm);