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author | Yinghai Lu <yinghai@kernel.org> | 2016-04-29 00:09:07 (GMT) |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-04-29 09:03:30 (GMT) |
commit | 4d2d542482205d3df1a0852751f5b004cc6390cc (patch) | |
tree | ce5aca3461a76427d62413c1a07484da6f9772f1 | |
parent | 67b6662559f7f77bcbd3ac67d09aaac11785f3c1 (diff) | |
download | linux-4d2d542482205d3df1a0852751f5b004cc6390cc.tar.xz |
x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size'
Since 'run_size' is now calculated in misc.c, the old script and associated
argument passing is no longer needed. This patch removes them, and renames
'run_size' to the more descriptive 'kernel_total_size'.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rewrote the changelog, renamed 'run_size' to 'kernel_total_size' ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1461888548-32439-6-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r-- | arch/x86/boot/compressed/Makefile | 4 | ||||
-rw-r--r-- | arch/x86/boot/compressed/head_32.S | 3 | ||||
-rw-r--r-- | arch/x86/boot/compressed/head_64.S | 3 | ||||
-rw-r--r-- | arch/x86/boot/compressed/misc.c | 11 | ||||
-rw-r--r-- | arch/x86/boot/compressed/mkpiggy.c | 10 | ||||
-rw-r--r-- | arch/x86/tools/calc_run_size.sh | 42 |
6 files changed, 8 insertions, 65 deletions
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 4599780..adef26d 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -121,10 +121,8 @@ suffix-$(CONFIG_KERNEL_XZ) := xz suffix-$(CONFIG_KERNEL_LZO) := lzo suffix-$(CONFIG_KERNEL_LZ4) := lz4 -RUN_SIZE = $(shell $(OBJDUMP) -h vmlinux | \ - $(CONFIG_SHELL) $(srctree)/arch/x86/tools/calc_run_size.sh) quiet_cmd_mkpiggy = MKPIGGY $@ - cmd_mkpiggy = $(obj)/mkpiggy $< $(RUN_SIZE) > $@ || ( rm -f $@ ; false ) + cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false ) targets += piggy.S $(obj)/piggy.S: $(obj)/vmlinux.bin.$(suffix-y) $(obj)/mkpiggy FORCE diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S index 8a95e2f..1038524 100644 --- a/arch/x86/boot/compressed/head_32.S +++ b/arch/x86/boot/compressed/head_32.S @@ -238,7 +238,6 @@ relocated: * Do the extraction, and jump to the new kernel.. */ /* push arguments for extract_kernel: */ - pushl $z_run_size /* size of kernel with .bss and .brk */ pushl $z_output_len /* decompressed length, end of relocs */ movl BP_init_size(%esi), %eax @@ -254,7 +253,7 @@ relocated: pushl %eax /* heap area */ pushl %esi /* real mode pointer */ call extract_kernel /* returns kernel location in %eax */ - addl $28, %esp + addl $24, %esp /* * Jump to the extracted kernel. diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 09cdc0c..7c04700 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -415,8 +415,6 @@ relocated: * Do the extraction, and jump to the new kernel.. */ pushq %rsi /* Save the real mode argument */ - movq $z_run_size, %r9 /* size of kernel with .bss and .brk */ - pushq %r9 movq %rsi, %rdi /* real mode address */ leaq boot_heap(%rip), %rsi /* malloc area for uncompression */ leaq input_data(%rip), %rdx /* input_data */ @@ -424,7 +422,6 @@ relocated: movq %rbp, %r8 /* output target address */ movq $z_output_len, %r9 /* decompressed length, end of relocs */ call extract_kernel /* returns kernel location in %rax */ - popq %r9 popq %rsi /* diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index cda93d1..bee6238 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -340,9 +340,9 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, unsigned char *input_data, unsigned long input_len, unsigned char *output, - unsigned long output_len, - unsigned long run_size) + unsigned long output_len) { + const unsigned long kernel_total_size = VO__end - VO__text; unsigned char *output_orig = output; /* Retain x86 boot parameters pointer passed from startup_32/64. */ @@ -364,8 +364,6 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, lines = boot_params->screen_info.orig_video_lines; cols = boot_params->screen_info.orig_video_cols; - run_size = VO__end - VO__text; - console_init(); debug_putstr("early console in extract_kernel\n"); @@ -377,7 +375,7 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, debug_putaddr(input_len); debug_putaddr(output); debug_putaddr(output_len); - debug_putaddr(run_size); + debug_putaddr(kernel_total_size); /* * The memory hole needed for the kernel is the larger of either @@ -385,8 +383,7 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, * entire decompressed kernel plus .bss and .brk sections. */ output = choose_random_location(input_data, input_len, output, - output_len > run_size ? output_len - : run_size); + max(output_len, kernel_total_size)); /* Validate memory location choices. */ if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1)) diff --git a/arch/x86/boot/compressed/mkpiggy.c b/arch/x86/boot/compressed/mkpiggy.c index f095ed9..72bad2c 100644 --- a/arch/x86/boot/compressed/mkpiggy.c +++ b/arch/x86/boot/compressed/mkpiggy.c @@ -34,13 +34,11 @@ int main(int argc, char *argv[]) { uint32_t olen; long ilen; - unsigned long run_size; FILE *f = NULL; int retval = 1; - if (argc < 3) { - fprintf(stderr, "Usage: %s compressed_file run_size\n", - argv[0]); + if (argc < 2) { + fprintf(stderr, "Usage: %s compressed_file\n", argv[0]); goto bail; } @@ -65,15 +63,11 @@ int main(int argc, char *argv[]) ilen = ftell(f); olen = get_unaligned_le32(&olen); - run_size = atoi(argv[2]); - printf(".section \".rodata..compressed\",\"a\",@progbits\n"); printf(".globl z_input_len\n"); printf("z_input_len = %lu\n", ilen); printf(".globl z_output_len\n"); printf("z_output_len = %lu\n", (unsigned long)olen); - printf(".globl z_run_size\n"); - printf("z_run_size = %lu\n", run_size); printf(".globl input_data, input_data_end\n"); printf("input_data:\n"); diff --git a/arch/x86/tools/calc_run_size.sh b/arch/x86/tools/calc_run_size.sh deleted file mode 100644 index 1a4c17b..0000000 --- a/arch/x86/tools/calc_run_size.sh +++ /dev/null @@ -1,42 +0,0 @@ -#!/bin/sh -# -# Calculate the amount of space needed to run the kernel, including room for -# the .bss and .brk sections. -# -# Usage: -# objdump -h a.out | sh calc_run_size.sh - -NUM='\([0-9a-fA-F]*[ \t]*\)' -OUT=$(sed -n 's/^[ \t0-9]*.b[sr][sk][ \t]*'"$NUM$NUM$NUM$NUM"'.*/\1\4/p') -if [ -z "$OUT" ] ; then - echo "Never found .bss or .brk file offset" >&2 - exit 1 -fi - -OUT=$(echo ${OUT# }) -sizeA=$(printf "%d" 0x${OUT%% *}) -OUT=${OUT#* } -offsetA=$(printf "%d" 0x${OUT%% *}) -OUT=${OUT#* } -sizeB=$(printf "%d" 0x${OUT%% *}) -OUT=${OUT#* } -offsetB=$(printf "%d" 0x${OUT%% *}) - -run_size=$(( $offsetA + $sizeA + $sizeB )) - -# BFD linker shows the same file offset in ELF. -if [ "$offsetA" -ne "$offsetB" ] ; then - # Gold linker shows them as consecutive. - endB=$(( $offsetB + $sizeB )) - if [ "$endB" != "$run_size" ] ; then - printf "sizeA: 0x%x\n" $sizeA >&2 - printf "offsetA: 0x%x\n" $offsetA >&2 - printf "sizeB: 0x%x\n" $sizeB >&2 - printf "offsetB: 0x%x\n" $offsetB >&2 - echo ".bss and .brk are non-contiguous" >&2 - exit 1 - fi -fi - -printf "%d\n" $run_size -exit 0 |