diff options
| author | Christoph Hellwig <hch@lst.de> | 2020-09-03 16:22:35 +0200 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2020-09-08 22:21:32 -0400 |
| commit | 5e6e9852d6f76e01b2e6803c74258afa5b432bc5 (patch) | |
| tree | 3b5f33348ea6302f3d6878f1c96e1631c4df9b0f /include/linux/uaccess.h | |
| parent | 36e2c7421f02a22f71c9283e55fdb672a9eb58e7 (diff) | |
uaccess: add infrastructure for kernel builds with set_fs()
Add a CONFIG_SET_FS option that is selected by architecturess that
implement set_fs, which is all of them initially. If the option is not
set stubs for routines related to overriding the address space are
provided so that architectures can start to opt out of providing set_fs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'include/linux/uaccess.h')
| -rw-r--r-- | include/linux/uaccess.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 94b285411659..70073c802b48 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -8,6 +8,7 @@ #include <asm/uaccess.h> +#ifdef CONFIG_SET_FS /* * Force the uaccess routines to be wired up for actual userspace access, * overriding any possible set_fs(KERNEL_DS) still lingering around. Undone @@ -25,6 +26,23 @@ static inline void force_uaccess_end(mm_segment_t oldfs) { set_fs(oldfs); } +#else /* CONFIG_SET_FS */ +typedef struct { + /* empty dummy */ +} mm_segment_t; + +#define uaccess_kernel() (false) +#define user_addr_max() (TASK_SIZE_MAX) + +static inline mm_segment_t force_uaccess_begin(void) +{ + return (mm_segment_t) { }; +} + +static inline void force_uaccess_end(mm_segment_t oldfs) +{ +} +#endif /* CONFIG_SET_FS */ /* * Architectures should provide two primitives (raw_copy_{to,from}_user()) |