From fc3562d79456bf1740b44d84b8726d20de8d39bd Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 8 Jun 2020 21:34:55 -0700 Subject: maccess: move user access routines together Move kernel access vs user access routines together to ease upcoming ifdefs. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Masami Hiramatsu Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20200521152301.2587579-18-hch@lst.de Signed-off-by: Linus Torvalds --- mm/maccess.c | 112 +++++++++++++++++++++++++++++------------------------------ 1 file changed, 56 insertions(+), 56 deletions(-) (limited to 'mm') diff --git a/mm/maccess.c b/mm/maccess.c index 253b786b2bf1..17b26bceb716 100644 --- a/mm/maccess.c +++ b/mm/maccess.c @@ -46,34 +46,6 @@ long probe_kernel_read(void *dst, const void *src, size_t size) } 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 * @dst: address to write to @@ -99,34 +71,6 @@ long probe_kernel_write(void *dst, const void *src, size_t size) 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 * address. @@ -170,6 +114,62 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count) 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 * address. -- cgit v1.2.3