linux-stable/include/linux/set_memory.h
Christophe Leroy 82ce8e2f31 set_memory: add __must_check to generic stubs
Following query shows that architectures that don't provide
asm/set_memory.h don't use set_memory_...() functions.

  $ git grep set_memory_ alpha arc csky hexagon loongarch m68k microblaze mips nios2 openrisc parisc sh sparc um xtensa

Following query shows that all core users of set_memory_...()
functions always take returned value into account:

  $ git grep -w -e set_memory_ro -e set_memory_rw -e set_memory_x -e set_memory_nx -e set_memory_rox `find . -maxdepth 1 -type d | grep -v arch | grep /`

set_memory_...() functions can fail, leaving the memory attributes
unchanged. Make sure all callers check the returned code.

Link: https://github.com/KSPP/linux/issues/7
Link: https://lkml.kernel.org/r/6a89ffc69666de84721216947c6b6c7dcca39d7d.1725723347.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <kees@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-17 01:07:00 -07:00

82 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright 2017, Michael Ellerman, IBM Corporation.
*/
#ifndef _LINUX_SET_MEMORY_H_
#define _LINUX_SET_MEMORY_H_
#ifdef CONFIG_ARCH_HAS_SET_MEMORY
#include <asm/set_memory.h>
#else
static inline int __must_check set_memory_ro(unsigned long addr, int numpages) { return 0; }
static inline int __must_check set_memory_rw(unsigned long addr, int numpages) { return 0; }
static inline int __must_check set_memory_x(unsigned long addr, int numpages) { return 0; }
static inline int __must_check set_memory_nx(unsigned long addr, int numpages) { return 0; }
#endif
#ifndef set_memory_rox
static inline int set_memory_rox(unsigned long addr, int numpages)
{
int ret = set_memory_ro(addr, numpages);
if (ret)
return ret;
return set_memory_x(addr, numpages);
}
#endif
#ifndef CONFIG_ARCH_HAS_SET_DIRECT_MAP
static inline int set_direct_map_invalid_noflush(struct page *page)
{
return 0;
}
static inline int set_direct_map_default_noflush(struct page *page)
{
return 0;
}
static inline bool kernel_page_present(struct page *page)
{
return true;
}
#else /* CONFIG_ARCH_HAS_SET_DIRECT_MAP */
/*
* Some architectures, e.g. ARM64 can disable direct map modifications at
* boot time. Let them overrive this query.
*/
#ifndef can_set_direct_map
static inline bool can_set_direct_map(void)
{
return true;
}
#define can_set_direct_map can_set_direct_map
#endif
#endif /* CONFIG_ARCH_HAS_SET_DIRECT_MAP */
#ifdef CONFIG_X86_64
int set_mce_nospec(unsigned long pfn);
int clear_mce_nospec(unsigned long pfn);
#else
static inline int set_mce_nospec(unsigned long pfn)
{
return 0;
}
static inline int clear_mce_nospec(unsigned long pfn)
{
return 0;
}
#endif
#ifndef CONFIG_ARCH_HAS_MEM_ENCRYPT
static inline int set_memory_encrypted(unsigned long addr, int numpages)
{
return 0;
}
static inline int set_memory_decrypted(unsigned long addr, int numpages)
{
return 0;
}
#endif /* CONFIG_ARCH_HAS_MEM_ENCRYPT */
#endif /* _LINUX_SET_MEMORY_H_ */