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x86/mm/init/32: Stop printing the virtual memory layout
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For security reasons, don't display the kernel's virtual memory layout.

Kees Cook points out:
"These have been entirely removed on other architectures, so let's
just do the same for ia32 and remove it unconditionally."

071929d ("arm64: Stop printing the virtual memory layout")
1c31d4e ("ARM: 8820/1: mm: Stop printing the virtual memory layout")
3183333 ("m68k/mm: Stop printing the virtual memory layout")
fd8d0ca ("parisc: Hide virtual kernel memory layout")
adb1fe9 ("mm/page_alloc: Remove kernel address exposure in free_reserved_area()")

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tycho Andersen <tycho@tycho.ws>
Acked-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200305150152.831697-1-nivedita@alum.mit.edu
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Arvind Sankar authored and Thomas Gleixner committed Mar 5, 2020
1 parent 98d54f8 commit 681ff01
Showing 1 changed file with 0 additions and 38 deletions.
38 changes: 0 additions & 38 deletions arch/x86/mm/init_32.c
Original file line number Diff line number Diff line change
Expand Up @@ -788,44 +788,6 @@ void __init mem_init(void)
x86_init.hyper.init_after_bootmem();

mem_init_print_info(NULL);
printk(KERN_INFO "virtual kernel memory layout:\n"
" fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
" cpu_entry : 0x%08lx - 0x%08lx (%4ld kB)\n"
#ifdef CONFIG_HIGHMEM
" pkmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
#endif
" vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
" lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n"
" .init : 0x%08lx - 0x%08lx (%4ld kB)\n"
" .data : 0x%08lx - 0x%08lx (%4ld kB)\n"
" .text : 0x%08lx - 0x%08lx (%4ld kB)\n",
FIXADDR_START, FIXADDR_TOP,
(FIXADDR_TOP - FIXADDR_START) >> 10,

CPU_ENTRY_AREA_BASE,
CPU_ENTRY_AREA_BASE + CPU_ENTRY_AREA_MAP_SIZE,
CPU_ENTRY_AREA_MAP_SIZE >> 10,

#ifdef CONFIG_HIGHMEM
PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
(LAST_PKMAP*PAGE_SIZE) >> 10,
#endif

VMALLOC_START, VMALLOC_END,
(VMALLOC_END - VMALLOC_START) >> 20,

(unsigned long)__va(0), (unsigned long)high_memory,
((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,

(unsigned long)&__init_begin, (unsigned long)&__init_end,
((unsigned long)&__init_end -
(unsigned long)&__init_begin) >> 10,

(unsigned long)&_etext, (unsigned long)&_edata,
((unsigned long)&_edata - (unsigned long)&_etext) >> 10,

(unsigned long)&_text, (unsigned long)&_etext,
((unsigned long)&_etext - (unsigned long)&_text) >> 10);

/*
* Check boundaries twice: Some fundamental inconsistencies can
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