x86: io-apic - interrupt remapping fix

Interrupt remapping could lead to NULL dereference in case of
kzalloc failed and memory leak in other way. So fix the
both cases.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 10 insertions, 3 deletions

diff --git a/arch/x86/kernel/apic.c b/arch/x86/kernel/apic.c
index 784116933c70..1f48bd1c9f2d 100644
--- a/arch/x86/kernel/apic.c
+++ b/arch/x86/kernel/apic.c
@@ -1360,7 +1360,12 @@ void enable_IR_x2apic(void)
 
         local_irq_save(flags);
         mask_8259A();
-        save_mask_IO_APIC_setup();
+
+        ret = save_mask_IO_APIC_setup();
+        if (ret) {
+                printk(KERN_INFO "Saving IO-APIC state failed: %d\n", ret);
+                goto end;
+        }
 
         ret = enable_intr_remapping(1);
 
@@ -1370,14 +1375,15 @@ void enable_IR_x2apic(void)
         }
 
         if (ret)
-                goto end;
+                goto end_restore;
 
         if (!x2apic) {
                 x2apic = 1;
                 apic_ops = &x2apic_ops;
                 enable_x2apic();
         }
-end:
+
+end_restore:
         if (ret)
                 /*
                  * IR enabling failed
@@ -1386,6 +1392,7 @@ end:
         else
                 reinit_intr_remapped_IO_APIC(x2apic_preenabled);
 
+end:
         unmask_8259A();
         local_irq_restore(flags);