[126/212] mm: change fault_in_pages_* to have an unsigned size parameter

Commit Message

Andrew Morton Sept. 2, 2021, 9:56 p.m. UTC

From: Greg Kroah-Hartman <[e-mail]>
Subject: mm: change fault_in_pages_* to have an unsigned size parameter

fault_in_pages_writeable() and fault_in_pages_readable() treat the size
parameter as unsigned, doing pointer math with the value, so make this
explicit and set it to be a size_t type which all callers currently treat
it as anyway.

This solves the issue where static checkers get nervous seeing pointer
arithmetic happening with a signed value.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>
Reported-by: Jordy Zomer <[e-mail]>
Cc: Matthew Wilcox <[e-mail]>
Cc: David Howells <[e-mail]>
Cc: William Kucharski <[e-mail]>
Cc: "Darrick J. Wong" <[e-mail]>
Cc: Hugh Dickins <[e-mail]>
Cc: Mauro Carvalho Chehab <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 include/linux/pagemap.h |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Patch

--- a/include/linux/pagemap.h~mm-change-fault_in_pages_-to-have-an-unsigned-size-parameter
+++ a/include/linux/pagemap.h
@@ -736,7 +736,7 @@  extern void add_page_wait_queue(struct p
 /*
  * Fault everything in given userspace address range in.
  */
-static inline int fault_in_pages_writeable(char __user *uaddr, int size)
+static inline int fault_in_pages_writeable(char __user *uaddr, size_t size)
 {
 	char __user *end = uaddr + size - 1;
 
@@ -763,7 +763,7 @@  static inline int fault_in_pages_writeab
 	return 0;
 }
 
-static inline int fault_in_pages_readable(const char __user *uaddr, int size)
+static inline int fault_in_pages_readable(const char __user *uaddr, size_t size)
 {
 	volatile char c;
 	const char __user *end = uaddr + size - 1;