linux_dsm_epyc7002/drivers/xen/xen-pciback
Gustavo A. R. Silva e8dc73c9f9 xen: 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 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200226212612.GA4663@embeddedor
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-03-05 09:41:58 -06:00
..
conf_space_capability.c xen-pciback: optionally allow interrupt enable flag writes 2020-01-15 16:50:13 -06:00
conf_space_header.c xen-pciback: optionally allow interrupt enable flag writes 2020-01-15 16:50:13 -06:00
conf_space_quirks.c xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in xen_pcibk_config_quirks_init 2018-04-16 10:20:31 -04:00
conf_space_quirks.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
conf_space.c xen-pciback: optionally allow interrupt enable flag writes 2020-01-15 16:50:13 -06:00
conf_space.h xen-pciback: optionally allow interrupt enable flag writes 2020-01-15 16:50:13 -06:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
passthrough.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pci_stub.c xen-pciback: optionally allow interrupt enable flag writes 2020-01-15 16:50:13 -06:00
pciback_ops.c xen/pciback: Don't disable PCI_COMMAND on PCI device reset. 2019-02-18 06:49:46 +01:00
pciback.h xen: Replace zero-length array with flexible-array member 2020-03-05 09:41:58 -06:00
vpci.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xenbus.c xen: xen-pciback: fix warning Using plain integer as NULL pointer 2019-04-23 11:15:09 -04:00