[tip: x86/mm] x86/mm/init/32: Stop printing the virtual memory layout - tip-bot2 for Arvind Sankar

From: "tip-bot2 for Arvind Sankar" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: Arvind Sankar <nivedita@alum.mit.edu>,
	Thomas Gleixner <tglx@linutronix.de>,
	Tycho Andersen <tycho@tycho.ws>,
	Kees Cook <keescook@chromium.org>, x86 <x86@kernel.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: [tip: x86/mm] x86/mm/init/32: Stop printing the virtual memory layout
Date: Thu, 05 Mar 2020 23:00:53 -0000	[thread overview]
Message-ID: <158344925342.28353.8367194721815610047.tip-bot2@tip-bot2> (raw)
In-Reply-To: <20200305150152.831697-1-nivedita@alum.mit.edu>

The following commit has been merged into the x86/mm branch of tip:

Commit-ID:     681ff0181bbfb183e32bc6beb6ec076304470479
Gitweb:        https://git.kernel.org/tip/681ff0181bbfb183e32bc6beb6ec076304470479
Author:        Arvind Sankar <nivedita@alum.mit.edu>
AuthorDate:    Thu, 05 Mar 2020 10:01:52 -05:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Thu, 05 Mar 2020 23:53:55 +01:00

x86/mm/init/32: Stop printing the virtual memory layout

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."

071929dbdd86 ("arm64: Stop printing the virtual memory layout")
1c31d4e96b8c ("ARM: 8820/1: mm: Stop printing the virtual memory layout")
31833332f798 ("m68k/mm: Stop printing the virtual memory layout")
fd8d0ca25631 ("parisc: Hide virtual kernel memory layout")
adb1fe9ae2ee ("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

---
 arch/x86/mm/init_32.c | 38 --------------------------------------
 1 file changed, 38 deletions(-)

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 23df488..8ae0272 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -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
