5dcd14ecd4
Use the new sentinel field to detect bootloaders which fail to follow protocol and don't initialize fields in struct boot_params that they do not explicitly initialize to zero. Based on an original patch and research by Yinghai Lu. Changed by hpa to be invoked both in the decompression path and in the kernel proper; the latter for the case where a bootloader takes over decompression. Originally-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1359058816-7615-26-git-send-email-yinghai@kernel.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
39 lines
1.2 KiB
C
39 lines
1.2 KiB
C
#ifndef _ASM_X86_BOOTPARAM_UTILS_H
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#define _ASM_X86_BOOTPARAM_UTILS_H
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#include <asm/bootparam.h>
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/*
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* This file is included from multiple environments. Do not
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* add completing #includes to make it standalone.
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*/
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/*
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* Deal with bootloaders which fail to initialize unknown fields in
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* boot_params to zero. The list fields in this list are taken from
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* analysis of kexec-tools; if other broken bootloaders initialize a
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* different set of fields we will need to figure out how to disambiguate.
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*
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*/
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static void sanitize_boot_params(struct boot_params *boot_params)
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{
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if (boot_params->sentinel) {
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/*fields in boot_params are not valid, clear them */
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memset(&boot_params->olpc_ofw_header, 0,
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(char *)&boot_params->alt_mem_k -
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(char *)&boot_params->olpc_ofw_header);
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memset(&boot_params->kbd_status, 0,
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(char *)&boot_params->hdr -
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(char *)&boot_params->kbd_status);
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memset(&boot_params->_pad7[0], 0,
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(char *)&boot_params->edd_mbr_sig_buffer[0] -
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(char *)&boot_params->_pad7[0]);
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memset(&boot_params->_pad8[0], 0,
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(char *)&boot_params->eddbuf[0] -
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(char *)&boot_params->_pad8[0]);
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memset(&boot_params->_pad9[0], 0, sizeof(boot_params->_pad9));
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}
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}
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#endif /* _ASM_X86_BOOTPARAM_UTILS_H */
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