[PATCH] FS-Cache: print hexadecimal value for special cookies type

From: JÃrÃmy Lefaure
Date: Wed Apr 19 2017 - 16:38:34 EST


When building object-list.o, gcc 6 raises a warning on the sprintf call
in fscache_objlist_show:

CC fs/fscache/object-list.o
fs/fscache/object-list.c: In function âfscache_objlist_showâ:
fs/fscache/object-list.c:265:19: warning: âsprintfâ may write a
terminating nul past the end of the destination [-Wformat-overflow=]
sprintf(_type, "%02u", cookie->def->type);
^~~~~~
fs/fscache/object-list.c:265:4: note: âsprintfâ output between 3 and 4
bytes into a destination of size 3
sprintf(_type, "%02u", cookie->def->type);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Moreover, the documentation says that we should have an hex value for
special cookies (see Documentation/filesystems/caching/fscache.txt).

Printing hexadecimal value for special cookies fixes the overflow
warning and complies with the documentation.

Signed-off-by: JÃrÃmy Lefaure <jeremy.lefaure@xxxxxxxxxxxx>
---
fs/fscache/object-list.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/fscache/object-list.c b/fs/fscache/object-list.c
index 67f940892ef8..d51303124889 100644
--- a/fs/fscache/object-list.c
+++ b/fs/fscache/object-list.c
@@ -262,7 +262,7 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
type = "DT";
break;
default:
- sprintf(_type, "%02u", cookie->def->type);
+ sprintf(_type, "%02x", cookie->def->type);
type = _type;
break;
}
--
2.12.2