Until commit f5a1a536fa14 ("lib: introduce copy_struct_from_user()
helper"), lib/usercopy.c was containing only the out-line version
of user copy fonctions.That commit added function check_zeroed_user() into the same file. Move that function into a new file named usercheck.c, so that next patch can change usercopy.c build to a conditional build. Signed-off-by: Christophe Leroy (CS GROUP) <[email protected]> --- lib/Makefile | 1 + lib/{usercopy.c => usercheck.c} | 22 ------------ lib/usercopy.c | 62 --------------------------------- 3 files changed, 1 insertion(+), 84 deletions(-) copy lib/{usercopy.c => usercheck.c} (73%) diff --git a/lib/Makefile b/lib/Makefile index f33a24bf1c19..7c0334d7675b 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -59,6 +59,7 @@ obj-y += bcd.o sort.o parser.o debug_locks.o random32.o \ percpu-refcount.o rhashtable.o base64.o \ once.o refcount.o rcuref.o usercopy.o errseq.o bucket_locks.o \ generic-radix-tree.o bitmap-str.o +obj-y += usercheck.o obj-y += string_helpers.o obj-y += hexdump.o obj-$(CONFIG_TEST_HEXDUMP) += test_hexdump.o diff --git a/lib/usercopy.c b/lib/usercheck.c similarity index 73% copy from lib/usercopy.c copy to lib/usercheck.c index b00a3a957de6..15b0d9a18435 100644 --- a/lib/usercopy.c +++ b/lib/usercheck.c @@ -2,32 +2,10 @@ #include <linux/compiler.h> #include <linux/errno.h> #include <linux/export.h> -#include <linux/fault-inject-usercopy.h> -#include <linux/instrumented.h> #include <linux/kernel.h> -#include <linux/nospec.h> -#include <linux/string.h> #include <linux/uaccess.h> #include <linux/wordpart.h> -/* out-of-line parts */ - -#if !defined(INLINE_COPY_FROM_USER) -unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n) -{ - return _inline_copy_from_user(to, from, n); -} -EXPORT_SYMBOL(_copy_from_user); -#endif - -#if !defined(INLINE_COPY_TO_USER) -unsigned long _copy_to_user(void __user *to, const void *from, unsigned long n) -{ - return _inline_copy_to_user(to, from, n); -} -EXPORT_SYMBOL(_copy_to_user); -#endif - /** * check_zeroed_user: check if a userspace buffer only contains zero bytes * @from: Source address, in userspace. diff --git a/lib/usercopy.c b/lib/usercopy.c index b00a3a957de6..7a93f56d81dd 100644 --- a/lib/usercopy.c +++ b/lib/usercopy.c @@ -1,14 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 -#include <linux/compiler.h> -#include <linux/errno.h> #include <linux/export.h> -#include <linux/fault-inject-usercopy.h> -#include <linux/instrumented.h> -#include <linux/kernel.h> -#include <linux/nospec.h> -#include <linux/string.h> #include <linux/uaccess.h> -#include <linux/wordpart.h> /* out-of-line parts */ @@ -27,57 +19,3 @@ unsigned long _copy_to_user(void __user *to, const void *from, unsigned long n) } EXPORT_SYMBOL(_copy_to_user); #endif - -/** - * check_zeroed_user: check if a userspace buffer only contains zero bytes - * @from: Source address, in userspace. - * @size: Size of buffer. - * - * This is effectively shorthand for "memchr_inv(from, 0, size) == NULL" for - * userspace addresses (and is more efficient because we don't care where the - * first non-zero byte is). - * - * Returns: - * * 0: There were non-zero bytes present in the buffer. - * * 1: The buffer was full of zero bytes. - * * -EFAULT: access to userspace failed. - */ -int check_zeroed_user(const void __user *from, size_t size) -{ - unsigned long val; - uintptr_t align = (uintptr_t) from % sizeof(unsigned long); - - if (unlikely(size == 0)) - return 1; - - from -= align; - size += align; - - if (!user_read_access_begin(from, size)) - return -EFAULT; - - unsafe_get_user(val, (unsigned long __user *) from, err_fault); - if (align) - val &= ~aligned_byte_mask(align); - - while (size > sizeof(unsigned long)) { - if (unlikely(val)) - goto done; - - from += sizeof(unsigned long); - size -= sizeof(unsigned long); - - unsafe_get_user(val, (unsigned long __user *) from, err_fault); - } - - if (size < sizeof(unsigned long)) - val &= aligned_byte_mask(size); - -done: - user_read_access_end(); - return (val == 0); -err_fault: - user_read_access_end(); - return -EFAULT; -} -EXPORT_SYMBOL(check_zeroed_user); -- 2.49.0
