From: Arvind Sankar <nivedita@alum.mit.edu>
To: "Tobin C . Harding" <me@tobin.cc>, Tycho Andersen <tycho@tycho.ws>
Cc: kernel-hardening@lists.openwall.com,
Dave Hansen <dave.hansen@linux.intel.com>,
Andy Lutomirski <luto@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
x86@kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] x86/mm/init_32: Don't print out kernel memory layout if KASLR
Date: Wed, 26 Feb 2020 16:50:39 -0500 [thread overview]
Message-ID: <20200226215039.2842351-1-nivedita@alum.mit.edu> (raw)
For security, only show the virtual kernel memory layout if KASLR is
disabled.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
---
arch/x86/mm/init_32.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 23df4885bbed..53635be69102 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -788,6 +788,10 @@ void __init mem_init(void)
x86_init.hyper.init_after_bootmem();
mem_init_print_info(NULL);
+
+ if (kaslr_enabled())
+ goto skip_layout;
+
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"
@@ -827,6 +831,7 @@ void __init mem_init(void)
(unsigned long)&_text, (unsigned long)&_etext,
((unsigned long)&_etext - (unsigned long)&_text) >> 10);
+skip_layout:
/*
* Check boundaries twice: Some fundamental inconsistencies can
* be detected at build time already.
--
2.24.1
next reply other threads:[~2020-02-26 21:50 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-26 21:50 Arvind Sankar [this message]
2020-02-29 23:51 ` [PATCH] x86/mm/init_32: Don't print out kernel memory layout if KASLR Kees Cook
2020-03-01 0:11 ` Arvind Sankar
2020-03-02 18:38 ` Kees Cook
2020-03-05 15:05 ` [PATCH] microblaze: Stop printing the virtual memory layout Arvind Sankar
2020-03-05 20:50 ` Tycho Andersen
2020-03-09 10:09 ` Michal Simek
2020-03-05 15:06 ` [PATCH] nds32/mm: " Arvind Sankar
2020-03-05 20:50 ` Tycho Andersen
2020-03-05 15:08 ` [PATCH] powerpc/32: " Arvind Sankar
2020-03-05 20:50 ` Tycho Andersen
2022-03-09 19:35 ` Christophe Leroy
2020-03-05 15:10 ` [PATCH] sh: " Arvind Sankar
2020-03-05 15:18 ` John Paul Adrian Glaubitz
2020-03-05 15:38 ` Joe Perches
2020-03-05 15:41 ` John Paul Adrian Glaubitz
2020-03-05 15:46 ` Arvind Sankar
2020-03-05 15:49 ` John Paul Adrian Glaubitz
2020-03-05 15:56 ` Arvind Sankar
2020-03-05 20:51 ` Tycho Andersen
2020-03-05 20:56 ` John Paul Adrian Glaubitz
2020-03-05 21:17 ` Kees Cook
2020-03-05 17:34 ` Kees Cook
2020-03-06 8:04 ` Geert Uytterhoeven
2020-03-08 12:17 ` Kaiwan N Billimoria
2020-03-05 15:11 ` [PATCH] xtensa/mm: " Arvind Sankar
2020-03-05 20:51 ` Tycho Andersen
2020-03-06 7:54 ` Max Filippov
2020-03-01 0:22 ` [PATCH v2] x86/mm/init_32: " Arvind Sankar
2020-03-02 15:29 ` Tycho Andersen
2020-03-02 18:39 ` Kees Cook
2020-03-05 15:01 ` [PATCH v3] " Arvind Sankar
2020-03-05 17:28 ` Kees Cook
2020-03-05 20:49 ` Tycho Andersen
2020-03-05 23:00 ` [tip: x86/mm] x86/mm/init/32: " tip-bot2 for Arvind Sankar
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