[tip:x86/mm] x86/mm: Unexport set_memory_ro() and set_memory_rw()

[tip-bot for Daniel Borkmann]

Commit-ID:  6bbb614ec478961c7443086bdf7fd6784479c14a
Gitweb:     http://git.kernel.org/tip/6bbb614ec478961c7443086bdf7fd6784479c14a
Author:     Daniel Borkmann <daniel@xxxxxxxxxxxxx>
AuthorDate: Fri, 27 Feb 2015 15:55:40 +0100
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Sat, 28 Feb 2015 10:41:59 +0100

x86/mm: Unexport set_memory_ro() and set_memory_rw()

This effectively unexports set_memory_ro() and set_memory_rw()
functions, and thus reverts:

  a03352d2c1dc ("x86: export set_memory_ro and set_memory_rw").

They have been introduced for debugging purposes in e1000e, but
no module user is in mainline kernel (anymore?) and we
explicitly do not want modules to use these functions, as they
i.e. protect eBPF (interpreted & JIT'ed) images from malicious
modifications or bugs.

Outside of eBPF scope, I believe also other set_memory_*()
functions should be unexported on x86 for modules.

Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Bruce Allan <bruce.w.allan@xxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Jesse Brandeburg <jesse.brandeburg@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: davem@xxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/a064393a0a5d319eebde5c761cfd743132d4f213.1425040940.git.daniel@xxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 arch/x86/mm/pageattr.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 536ea2f..81e8282 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -1654,13 +1654,11 @@ int set_memory_ro(unsigned long addr, int numpages)
 {
 	return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0);
 }
-EXPORT_SYMBOL_GPL(set_memory_ro);
 
 int set_memory_rw(unsigned long addr, int numpages)
 {
 	return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0);
 }
-EXPORT_SYMBOL_GPL(set_memory_rw);
 
 int set_memory_np(unsigned long addr, int numpages)
 {
--
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