Commit 4fb60b15 authored Jul 24, 2020 by Kees Cook Committed by Greg Kroah-Hartman Jul 25, 2020

firmware_loader: EFI firmware loader must handle pre-allocated buffer



The EFI platform firmware fallback would clobber any pre-allocated
buffers. Instead, correctly refuse to reallocate when too small (as
already done in the sysfs fallback), or perform allocation normally
when needed.

Fixes: e4c2c0ff ("firmware: Add new platform fallback mechanism and firmware_request_platform()")
Cc: stable@vger.kernel.org
Acked-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200724213640.389191-4-keescook@chromium.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 4505e215

drivers/base/firmware_loader/fallback_platform.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -25,6 +25,9 @@ int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags)
		if (rc)
		return rc; /* rc == -ENOENT when the fw was not found */

		if (fw_priv->data && size > fw_priv->allocated_size)
		return -ENOMEM;
		if (!fw_priv->data)
		fw_priv->data = vmalloc(size);
		if (!fw_priv->data)
		return -ENOMEM;

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