Commit-ID: 549f90db68c9f8e21a40ec21c8047441984e7164 Gitweb: http://git.kernel.org/tip/549f90db68c9f8e21a40ec21c8047441984e7164 Author: Borislav Petkov <b...@suse.de> AuthorDate: Fri, 6 May 2016 13:50:15 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Sat, 7 May 2016 07:38:38 +0200
x86/boot: Simplify pointer casting in choose_random_location() Pass them down as 'unsigned long' directly and get rid of more casting and assignments. Signed-off-by: Borislav Petkov <b...@suse.de> Cc: Andy Lutomirski <l...@amacapital.net> Cc: Borislav Petkov <b...@alien8.de> Cc: Brian Gerst <brge...@gmail.com> Cc: Denys Vlasenko <dvlas...@redhat.com> Cc: H. Peter Anvin <h...@zytor.com> Cc: Kees Cook <keesc...@chromium.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: a...@linux-foundation.org Cc: b...@redhat.com Cc: dyo...@redhat.com Cc: linux-tip-comm...@vger.kernel.org Cc: l...@kernel.org Cc: vgo...@redhat.com Cc: ying...@kernel.org Link: http://lkml.kernel.org/r/20160506115015.gi24...@pd.tnic Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/boot/compressed/kaslr.c | 17 ++++++----------- arch/x86/boot/compressed/misc.c | 3 ++- arch/x86/boot/compressed/misc.h | 10 +++++----- 3 files changed, 13 insertions(+), 17 deletions(-) diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 6392f00..ff12277 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -350,20 +350,15 @@ static unsigned long find_random_addr(unsigned long minimum, return slots_fetch_random(); } -unsigned char *choose_random_location(unsigned char *input_ptr, +/* + * Since this function examines addresses much more numerically, + * it takes the input and output pointers as 'unsigned long'. + */ +unsigned char *choose_random_location(unsigned long input, unsigned long input_size, - unsigned char *output_ptr, + unsigned long output, unsigned long output_size) { - /* - * The caller of choose_random_location() uses unsigned char * for - * buffer pointers since it performs decompression, elf parsing, etc. - * Since this code examines addresses much more numerically, - * unsigned long is used internally here. Instead of sprinkling - * more casts into extract_kernel, do them here and at return. - */ - unsigned long input = (unsigned long)input_ptr; - unsigned long output = (unsigned long)output_ptr; unsigned long choice = output; unsigned long random_addr; diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index 9536d77..f14db4e 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -366,7 +366,8 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, * the entire decompressed kernel plus relocation table, or the * entire decompressed kernel plus .bss and .brk sections. */ - output = choose_random_location(input_data, input_len, output, + output = choose_random_location((unsigned long)input_data, input_len, + (unsigned long)output, max(output_len, kernel_total_size)); /* Validate memory location choices. */ diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 1f23d02..0112005a 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -67,20 +67,20 @@ int cmdline_find_option_bool(const char *option); #if CONFIG_RANDOMIZE_BASE /* kaslr.c */ -unsigned char *choose_random_location(unsigned char *input_ptr, +unsigned char *choose_random_location(unsigned long input_ptr, unsigned long input_size, - unsigned char *output_ptr, + unsigned long output_ptr, unsigned long output_size); /* cpuflags.c */ bool has_cpuflag(int flag); #else static inline -unsigned char *choose_random_location(unsigned char *input_ptr, +unsigned char *choose_random_location(unsigned long input_ptr, unsigned long input_size, - unsigned char *output_ptr, + unsigned long output_ptr, unsigned long output_size) { - return output_ptr; + return (unsigned char *)output_ptr; } #endif
