Commit 5ffa4eb2 authored by Cyrill Gorcunov's avatar Cyrill Gorcunov Committed by Ingo Molnar
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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: default avatarCyrill Gorcunov <gorcunov@gmail.com>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 2976fe20

arch/x86/kernel/apic.c

+10 −3
Original line number Diff line number Diff line
@@ -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);

arch/x86/kernel/io_apic.c

+17 −2
Original line number Diff line number Diff line
@@ -812,7 +812,7 @@ int save_mask_IO_APIC_setup(void) 
			kzalloc(sizeof(struct IO_APIC_route_entry) *

				nr_ioapic_registers[apic], GFP_KERNEL);

		if (!early_ioapic_entries[apic])

			return -ENOMEM;

			goto nomem;

	}



	for (apic = 0; apic < nr_ioapics; apic++)
@@ -826,17 +826,32 @@ int save_mask_IO_APIC_setup(void) 
				ioapic_write_entry(apic, pin, entry);

			}

		}



	return 0;



nomem:

	for (; apic > 0; apic--)

		kfree(early_ioapic_entries[apic]);

	kfree(early_ioapic_entries[apic]);

	memset(early_ioapic_entries, 0,

		ARRAY_SIZE(early_ioapic_entries));



	return -ENOMEM;

}



void restore_IO_APIC_setup(void)

{

	int apic, pin;



	for (apic = 0; apic < nr_ioapics; apic++)

	for (apic = 0; apic < nr_ioapics; apic++) {

		if (!early_ioapic_entries[apic])

			break;

		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++)

			ioapic_write_entry(apic, pin,

					   early_ioapic_entries[apic][pin]);

		kfree(early_ioapic_entries[apic]);

		early_ioapic_entries[apic] = NULL;

	}

}



void reinit_intr_remapped_IO_APIC(int intr_remapping)

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