From 2cce23ea9be708eeeb6cbefaf25f20c89d89f62b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 8 Jun 2020 21:34:47 -0700 Subject: [PATCH] BACKPORT: maccess: remove strncpy_from_unsafe All users are gone now. 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/20200521152301.2587579-16-hch@lst.de Signed-off-by: Linus Torvalds Change-Id: Id1d12538ec284c86e4eb7b0d35e7bea07b20d617 --- include/linux/uaccess.h | 1 - mm/maccess.c | 38 -------------------------------------- 2 files changed, 39 deletions(-) diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 3b8b83b4b062..2747771d64e9 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -313,7 +313,6 @@ extern long probe_user_read(void *dst, const void __user *src, size_t size); extern long notrace probe_kernel_write(void *dst, const void *src, size_t size); extern long notrace probe_user_write(void __user *dst, const void *src, size_t size); -extern long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count); long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count); diff --git a/mm/maccess.c b/mm/maccess.c index b82c6862c2ef..b30f22c425f4 100644 --- a/mm/maccess.c +++ b/mm/maccess.c @@ -6,9 +6,6 @@ #include #include -static long __strncpy_from_unsafe(char *dst, const void *unsafe_addr, - long count, bool strict); - bool __weak probe_kernel_read_allowed(const void *unsafe_src, size_t size) { return true; @@ -131,35 +128,6 @@ long probe_user_write(void __user *dst, const void *src, size_t size) } EXPORT_SYMBOL_GPL(probe_user_write); -/** - * strncpy_from_unsafe: - Copy a NUL terminated string from unsafe address. - * @dst: Destination address, in kernel space. This buffer must be at - * least @count bytes long. - * @unsafe_addr: Unsafe address. - * @count: Maximum number of bytes to copy, including the trailing NUL. - * - * Copies a NUL-terminated string from unsafe address to kernel buffer. - * - * On success, returns the length of the string INCLUDING the trailing NUL. - * - * If access fails, returns -EFAULT (some data may have been copied - * and the trailing NUL added). - * - * If @count is smaller than the length of the string, copies @count-1 bytes, - * sets the last byte of @dst buffer to NUL and returns @count. - * - * Same as strncpy_from_kernel_nofault() except that for architectures with - * not fully separated user and kernel address spaces this function also works - * for user address tanges. - * - * DO NOT USE THIS FUNCTION - it is broken on architectures with entirely - * separate kernel and user address spaces, and also a bad idea otherwise. - */ -long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count) -{ - return __strncpy_from_unsafe(dst, unsafe_addr, count, false); -} - /** * strncpy_from_kernel_nofault: - Copy a NUL terminated string from unsafe * address. @@ -179,12 +147,6 @@ long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count) * sets the last byte of @dst buffer to NUL and returns @count. */ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count) -{ - return __strncpy_from_unsafe(dst, unsafe_addr, count, true); -} - -static long __strncpy_from_unsafe(char *dst, const void *unsafe_addr, - long count, bool strict) { mm_segment_t old_fs = get_fs(); const void *src = unsafe_addr;