WSL2-Linux-Kernel/include
Gustavo A. R. Silva 00b42b70ae scsi: libsas: Replace zero-length array with flexible-array
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]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in which
the sizeof operator is being incorrectly/erroneously applied to zero-length
arrays and the result is zero. Such instances may be hiding some bugs. So,
this work (flexible-array member conversions) will also help to get
completely rid of those sorts of issues.

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")

Link: https://lore.kernel.org/r/20200507192147.GA16206@embeddedor
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-11 22:26:32 -04:00
..
acpi Additional ACPI updates for 5.7-rc1 2020-04-06 10:35:06 -07:00
asm-generic userfaultfd: wp: add pmd_swp_*uffd_wp() helpers 2020-04-07 10:43:39 -07:00
clocksource pwm: omap-dmtimer: Drop unused header file 2020-03-30 18:03:06 +02:00
crypto crypto: curve25519 - do not pollute dispatcher based on assembler 2020-04-09 00:01:59 +09:00
drm drm/bridge: analogix_dp: Split bind() into probe() and real bind() 2020-04-09 10:29:35 +02:00
dt-bindings RISC-V Patches for the 5.7 Merge Window, Part 1 2020-04-09 10:51:30 -07:00
keys KEYS: Don't write out to userspace while holding key semaphore 2020-03-29 12:40:41 +01:00
kunit kunit: subtests should be indented 4 spaces according to TAP 2020-03-26 14:08:41 -06:00
kvm KVM: arm64: GICv4.1: Allow SGIs to switch between HW and SW interrupts 2020-03-24 12:15:51 +00:00
linux scsi: qed: Send BW update notifications to the protocol drivers 2020-04-17 17:55:26 -04:00
math-emu
media media: cec-notifier: make cec_notifier_get_conn() static 2020-03-20 09:02:45 +01:00
misc
net 9p pull request for inclusion in 5.7 2020-04-06 08:46:59 -07:00
pcmcia
ras
rdma IB/mlx5: Expose UAR object and its alloc/destroy commands 2020-03-27 12:59:04 -03:00
scsi scsi: libsas: Replace zero-length array with flexible-array 2020-05-11 22:26:32 -04:00
soc ARM: driver updates 2020-04-03 15:05:35 -07:00
sound ASoC: Fixes for v5.7 2020-04-08 18:08:09 +02:00
target scsi: target: tcmu: Make pgr_support and alua_support attributes writable 2020-05-07 22:39:22 -04:00
trace Merge branch 'akpm' (patches from Andrew) 2020-04-07 14:11:54 -07:00
uapi IOMMU Updates for Linux v5.7 2020-04-08 11:00:00 -07:00
vdso vdso: Fix clocksource.h macro detection 2020-03-23 18:51:08 +01:00
video video: Replace zero-length array with flexible-array member 2020-03-02 16:32:17 +01:00
xen xen: Use evtchn_type_t as a type for event channels 2020-04-07 12:12:54 +02:00