linux_dsm_epyc7002/include/soc/fsl
Gustavo A. R. Silva 661ea25e53 soc: fsl: qe: Replace one-element array and use struct_size() helper
The current codebase makes use of one-element arrays in the following
form:

struct something {
    int length;
    u8 data[1];
};

struct something *instance;

instance = kmalloc(sizeof(*instance) + size, GFP_KERNEL);
instance->length = size;
memcpy(instance->data, source, size);

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. So, replace
the one-element array with a flexible-array member.

Also, make use of the new struct_size() helper to properly calculate the
size of struct qe_firmware.

This issue was found with the help of Coccinelle and, audited and fixed
_manually_.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Qiang Zhao <qiang.zhao@nxp.com>
Signed-off-by: Li Yang <leoyang.li@nxp.com>
2020-05-22 16:23:02 -05:00
..
qe soc: fsl: qe: Replace one-element array and use struct_size() helper 2020-05-22 16:23:02 -05:00
bman.h soc: fsl: qbman_portals: add APIs to retrieve the probing status 2019-05-20 14:28:16 -05:00
cpm.h soc: fsl: move cpm.h from powerpc/include/asm to include/soc/fsl 2019-12-09 13:54:34 -06:00
dpaa2-fd.h soc: fsl: dpio: add frame list format support 2018-09-21 13:24:50 +08:00
dpaa2-global.h soc: fsl: dpio: add congestion notification support 2018-09-21 13:24:50 +08:00
dpaa2-io.h soc: fsl: dpio: Adding QMAN multiple enqueue interface 2020-02-19 18:06:16 -06:00
qman.h dpaa_eth: register a device link for the qman portal used 2019-10-31 12:13:34 -07:00