linux/include
Gustavo A. R. Silva dfd500d895 fs: nfs: acl: Avoid -Wflex-array-member-not-at-end warning
-Wflex-array-member-not-at-end was introduced in GCC-14, and we are
getting ready to enable it, globally.

So, in order to avoid ending up with a flexible-array member in the
middle of other structs, we use the `struct_group_tagged()` helper
to create a new tagged `struct posix_acl_hdr`. This structure
groups together all the members of the flexible `struct posix_acl`
except the flexible array.

As a result, the array is effectively separated from the rest of the
members without modifying the memory layout of the flexible structure.
We then change the type of the middle struct member currently causing
trouble from `struct posix_acl` to `struct posix_acl_hdr`.

We also want to ensure that when new members need to be added to the
flexible structure, they are always included within the newly created
tagged struct. For this, we use `static_assert()`. This ensures that the
memory layout for both the flexible structure and the new tagged struct
is the same after any changes.

This approach avoids having to implement `struct posix_acl_hdr` as a
completely separate structure, thus preventing having to maintain two
independent but basically identical structures, closing the door to
potential bugs in the future.

We also use `container_of()` whenever we need to retrieve a pointer to
the flexible structure, through which we can access the flexible-array
member, if necessary.

So, with these changes, fix the following warning:

fs/nfs_common/nfsacl.c:45:26: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2025-03-10 09:11:04 -04:00
..
acpi LoongArch changes for v6.14 2025-01-28 08:52:01 -08:00
asm-generic arm64 fixes for -rc5 2025-03-01 13:44:51 -08:00
clocksource KVM/arm64 updates for 6.14 2025-01-28 09:01:36 -08:00
crypto
cxl
drm drm: Fix DSC BPP increment decoding 2025-02-13 10:20:30 +02:00
dt-bindings dt-bindings: clock: qcom: Add CAMCC clocks for QCS8300 2025-02-02 20:59:04 -06:00
hyperv
keys
kunit linux_kselftest-kunit-6.14-rc1 2025-01-22 12:32:39 -08:00
kvm
linux fs: nfs: acl: Avoid -Wflex-array-member-not-at-end warning 2025-03-10 09:11:04 -04:00
math-emu
media
memory
misc
net Including fixes from bluetooth. We didn't get netfilter or wireless PRs 2025-02-27 09:32:42 -08:00
pcmcia
ras
rdma
rv rv: Reset per-task monitors also for idle tasks 2025-01-23 12:16:04 -05:00
scsi Driver core and debugfs updates 2025-01-28 12:25:12 -08:00
soc soc: driver updates for 6.14 2025-01-24 14:56:59 -08:00
sound ASoC: cs35l56: Prevent races when soft-resetting using SPI control 2025-02-25 15:06:58 +00:00
target
trace Including fixes from bluetooth. We didn't get netfilter or wireless PRs 2025-02-27 09:32:42 -08:00
uapi lockd: add netlink control interface 2025-03-10 09:10:53 -04:00
ufs scsi: ufs: core: Fix use-after free in init error and remove paths 2025-02-03 17:20:01 -05:00
vdso
video
xen