diff options
author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-27 01:27:22 +0300 |
---|---|---|
committer | Miquel Raynal <miquel.raynal@bootlin.com> | 2020-03-11 18:17:54 +0300 |
commit | 49f1c33076ca56871ffddc4800b04524204ea889 (patch) | |
tree | daa5aa45f8538c85b95dd1479f8358131c961b26 /drivers/mtd/nand/raw/mtk_nand.c | |
parent | c6fbcb70132ffc66696a94dd3d8e6215c750254f (diff) | |
download | linux-49f1c33076ca56871ffddc4800b04524204ea889.tar.xz |
mtd: rawnand: 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
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
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>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200226222722.GA18020@embeddedor
Diffstat (limited to 'drivers/mtd/nand/raw/mtk_nand.c')
-rw-r--r-- | drivers/mtd/nand/raw/mtk_nand.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/mtd/nand/raw/mtk_nand.c b/drivers/mtd/nand/raw/mtk_nand.c index b8305e39ab51..ef149e8b26d0 100644 --- a/drivers/mtd/nand/raw/mtk_nand.c +++ b/drivers/mtd/nand/raw/mtk_nand.c @@ -131,7 +131,7 @@ struct mtk_nfc_nand_chip { u32 spare_per_sector; int nsels; - u8 sels[0]; + u8 sels[]; /* nothing after this field */ }; |