Commit fc3562d7 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Linus Torvalds

maccess: move user access routines together

Move kernel access vs user access routines together to ease upcoming
ifdefs.
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-18-hch@lst.deSigned-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 98a23609
...@@ -46,34 +46,6 @@ long probe_kernel_read(void *dst, const void *src, size_t size) ...@@ -46,34 +46,6 @@ long probe_kernel_read(void *dst, const void *src, size_t size)
} }
EXPORT_SYMBOL_GPL(probe_kernel_read); EXPORT_SYMBOL_GPL(probe_kernel_read);
/**
* probe_user_read(): safely attempt to read from a user-space location
* @dst: pointer to the buffer that shall take the data
* @src: address to read from. This must be a user address.
* @size: size of the data chunk
*
* Safely read from user address @src to the buffer at @dst. If a kernel fault
* happens, handle that and return -EFAULT.
*/
long probe_user_read(void *dst, const void __user *src, size_t size)
{
long ret = -EFAULT;
mm_segment_t old_fs = get_fs();
set_fs(USER_DS);
if (access_ok(src, size)) {
pagefault_disable();
ret = __copy_from_user_inatomic(dst, src, size);
pagefault_enable();
}
set_fs(old_fs);
if (ret)
return -EFAULT;
return 0;
}
EXPORT_SYMBOL_GPL(probe_user_read);
/** /**
* probe_kernel_write(): safely attempt to write to a location * probe_kernel_write(): safely attempt to write to a location
* @dst: address to write to * @dst: address to write to
...@@ -99,34 +71,6 @@ long probe_kernel_write(void *dst, const void *src, size_t size) ...@@ -99,34 +71,6 @@ long probe_kernel_write(void *dst, const void *src, size_t size)
return 0; return 0;
} }
/**
* probe_user_write(): safely attempt to write to a user-space location
* @dst: address to write to
* @src: pointer to the data that shall be written
* @size: size of the data chunk
*
* Safely write to address @dst from the buffer at @src. If a kernel fault
* happens, handle that and return -EFAULT.
*/
long probe_user_write(void __user *dst, const void *src, size_t size)
{
long ret = -EFAULT;
mm_segment_t old_fs = get_fs();
set_fs(USER_DS);
if (access_ok(dst, size)) {
pagefault_disable();
ret = __copy_to_user_inatomic(dst, src, size);
pagefault_enable();
}
set_fs(old_fs);
if (ret)
return -EFAULT;
return 0;
}
EXPORT_SYMBOL_GPL(probe_user_write);
/** /**
* strncpy_from_kernel_nofault: - Copy a NUL terminated string from unsafe * strncpy_from_kernel_nofault: - Copy a NUL terminated string from unsafe
* address. * address.
...@@ -170,6 +114,62 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count) ...@@ -170,6 +114,62 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count)
return ret ? -EFAULT : src - unsafe_addr; return ret ? -EFAULT : src - unsafe_addr;
} }
/**
* probe_user_read(): safely attempt to read from a user-space location
* @dst: pointer to the buffer that shall take the data
* @src: address to read from. This must be a user address.
* @size: size of the data chunk
*
* Safely read from user address @src to the buffer at @dst. If a kernel fault
* happens, handle that and return -EFAULT.
*/
long probe_user_read(void *dst, const void __user *src, size_t size)
{
long ret = -EFAULT;
mm_segment_t old_fs = get_fs();
set_fs(USER_DS);
if (access_ok(src, size)) {
pagefault_disable();
ret = __copy_from_user_inatomic(dst, src, size);
pagefault_enable();
}
set_fs(old_fs);
if (ret)
return -EFAULT;
return 0;
}
EXPORT_SYMBOL_GPL(probe_user_read);
/**
* probe_user_write(): safely attempt to write to a user-space location
* @dst: address to write to
* @src: pointer to the data that shall be written
* @size: size of the data chunk
*
* Safely write to address @dst from the buffer at @src. If a kernel fault
* happens, handle that and return -EFAULT.
*/
long probe_user_write(void __user *dst, const void *src, size_t size)
{
long ret = -EFAULT;
mm_segment_t old_fs = get_fs();
set_fs(USER_DS);
if (access_ok(dst, size)) {
pagefault_disable();
ret = __copy_to_user_inatomic(dst, src, size);
pagefault_enable();
}
set_fs(old_fs);
if (ret)
return -EFAULT;
return 0;
}
EXPORT_SYMBOL_GPL(probe_user_write);
/** /**
* strncpy_from_user_nofault: - Copy a NUL terminated string from unsafe user * strncpy_from_user_nofault: - Copy a NUL terminated string from unsafe user
* address. * address.
......
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