Commit 741c5640 authored Jul 02, 2018 by Kees Cook Committed by Michael Ellerman Jul 03, 2018

powerpc/mpc5200: Remove VLA usage

In the quest to remove all stack VLA usage from the kernel[1], this
switches to using a stack size large enough for the saved routine and
adds a sanity check making sure the routine doesn't overflow into the
0x600 exception handler.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com



Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent d497ebf5

arch/powerpc/platforms/52xx/mpc52xx_pm.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -117,7 +117,10 @@ int mpc52xx_pm_enter(suspend_state_t state)
		u32 intr_main_mask;
		void __iomem * irq_0x500 = (void __iomem *)CONFIG_KERNEL_START + 0x500;
		unsigned long irq_0x500_stop = (unsigned long)irq_0x500 + mpc52xx_ds_cached_size;
		char saved_0x500[mpc52xx_ds_cached_size];
		char saved_0x500[0x600-0x500];

		if (WARN_ON(mpc52xx_ds_cached_size > sizeof(saved_0x500)))
		return -ENOMEM;

		/* disable all interrupts in PIC */
		intr_main_mask = in_be32(&intr->main_mask);

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