From f3cafd18425b11efc3607be2ef2f8fa17c045639 Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Wed, 25 Apr 2012 11:02:37 +1000 Subject: [PATCH] pagemap.h: fix warning about possibly used before init var Commit f56f821feb7b36223f309e0ec05986bb137ce418 (linux-next) "mm: extend prefault helpers to fault in more than PAGE_SIZE" added in the new functions: fault_in_multipages_writeable fault_in_multipages_readable However, we currently see: include/linux/pagemap.h:492: warning: 'ret' may be used uninitialized in this function include/linux/pagemap.h:492: note: 'ret' was declared here Unlike a lot of gcc nags, this one appears somewhat legit. i.e. passing in an invalid negative value of "size" does make it look like all the conditionals in there would be bypassed and the uninitialized value would be returned. Signed-off-by: Paul Gortmaker Cc: Daniel Vetter Signed-off-by: Andrew Morton --- include/linux/pagemap.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index efa26b4da8d2..7cfad3bbb0cc 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -460,11 +460,11 @@ static inline int fault_in_pages_readable(const char __user *uaddr, int size) */ static inline int fault_in_multipages_writeable(char __user *uaddr, int size) { - int ret; + int ret = 0; char __user *end = uaddr + size - 1; if (unlikely(size == 0)) - return 0; + return ret; /* * Writing zeroes into userspace here is OK, because we know that if @@ -489,11 +489,11 @@ static inline int fault_in_multipages_readable(const char __user *uaddr, int size) { volatile char c; - int ret; + int ret = 0; const char __user *end = uaddr + size - 1; if (unlikely(size == 0)) - return 0; + return ret; while (uaddr <= end) { ret = __get_user(c, uaddr); -- 2.39.5