summary refs log tree commit diff
path: root/lib
diff options
context:
space:
mode:
authorGustavo A. R. Silva <gustavo@embeddedor.com>2020-04-06 20:10:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-04-07 10:43:42 -0700
commitc6e2ac3b476b458f9bd2069d85b95ca4634ce680 (patch)
treef8225e10a69bae399c9c7f7b5685b02080029b8f /lib
parenta44ce5137026493b3bec3768cff92861dbeede5c (diff)
downloadlinux-c6e2ac3b476b458f9bd2069d85b95ca4634ce680.tar.gz
lib/ts_bm.c: replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language extension
to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning in
case the flexible array does not occur last in the structure, which will
help us prevent some kind of undefined behavior bugs from being
inadvertenly introduced[3] to the codebase from now on.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200211205620.GA24694@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
-rw-r--r--lib/ts_bm.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/ts_bm.c b/lib/ts_bm.c
index b352903c50e3..277cb4417ac2 100644
--- a/lib/ts_bm.c
+++ b/lib/ts_bm.c
@@ -52,7 +52,7 @@ struct ts_bm
 	u8 *		pattern;
 	unsigned int	patlen;
 	unsigned int 	bad_shift[ASIZE];
-	unsigned int	good_shift[0];
+	unsigned int	good_shift[];
 };
 
 static unsigned int bm_find(struct ts_config *conf, struct ts_state *state)