[ndctl PATCH] ndctl/lib: move nd_cmd_pkg with a flex array to end of structures

[Alison Schofield <alison.schofield@intel.com>]

Placing nd_cmd_pkg anywhere but at the end of a structure can lead to
undefined behavior for the flex array member. Move nd_cmd_pkg to the
end of all affected structures.

Reproduce using Clang:
~/git/ndctl$ rm -rf build
~/git/ndctl$ CC=clang meson setup build
~/git/ndctl$ meson compile -C build

../ndctl/lib/hpe1.h:324:20: warning: field 'gen' with variable sized type 'struct nd_cmd_pkg' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end]

Reported-by: Cristian Rodriguez <yo@cristianrodriguez.net>
Closes: https://github.com/pmem/ndctl/issues/296
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
---
 ndctl/lib/hpe1.h      | 2 +-
 ndctl/lib/hyperv.h    | 2 +-
 ndctl/lib/intel.h     | 2 +-
 ndctl/lib/msft.h      | 2 +-
 ndctl/lib/papr.h      | 2 +-
 ndctl/libndctl-nfit.h | 2 +-
 6 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/ndctl/lib/hpe1.h b/ndctl/lib/hpe1.h
index bc19f72ca8d0..99d8f57eb8e0 100644
--- a/ndctl/lib/hpe1.h
+++ b/ndctl/lib/hpe1.h
@@ -321,8 +321,8 @@ union ndn_hpe1_cmd {
 };
 
 struct ndn_pkg_hpe1 {
-	struct nd_cmd_pkg gen;
 	union ndn_hpe1_cmd u;
+	struct nd_cmd_pkg gen;
 } __attribute__((packed));
 
 #define NDN_IOCTL_HPE1_PASSTHRU		_IOWR(ND_IOCTL, ND_CMD_CALL, \
diff --git a/ndctl/lib/hyperv.h b/ndctl/lib/hyperv.h
index 45741c7cdd17..9157f1563632 100644
--- a/ndctl/lib/hyperv.h
+++ b/ndctl/lib/hyperv.h
@@ -31,8 +31,8 @@ union nd_hyperv_cmd {
 } __attribute__((packed));
 
 struct nd_pkg_hyperv {
-	struct nd_cmd_pkg	gen;
 	union  nd_hyperv_cmd	u;
+	struct nd_cmd_pkg	gen;
 } __attribute__((packed));
 
 #endif /* __NDCTL_HYPERV_H__ */
diff --git a/ndctl/lib/intel.h b/ndctl/lib/intel.h
index 5aee98062a84..09f8cf7745ce 100644
--- a/ndctl/lib/intel.h
+++ b/ndctl/lib/intel.h
@@ -141,7 +141,6 @@ struct nd_intel_lss {
 } __attribute__((packed));
 
 struct nd_pkg_intel {
-	struct nd_cmd_pkg gen;
 	union {
 		struct nd_intel_smart smart;
 		struct nd_intel_smart_inject inject;
@@ -154,6 +153,7 @@ struct nd_pkg_intel {
 		struct nd_intel_fw_finish_query fquery;
 		struct nd_intel_lss lss;
 	};
+	struct nd_cmd_pkg gen;
 };
 
 #define ND_INTEL_STATUS_MASK		0xffff
diff --git a/ndctl/lib/msft.h b/ndctl/lib/msft.h
index 8d246a5ed137..65789950abe1 100644
--- a/ndctl/lib/msft.h
+++ b/ndctl/lib/msft.h
@@ -41,8 +41,8 @@ union ndn_msft_cmd {
 } __attribute__((packed));
 
 struct ndn_pkg_msft {
-	struct nd_cmd_pkg	gen;
 	union ndn_msft_cmd	u;
+	struct nd_cmd_pkg	gen;
 } __attribute__((packed));
 
 #define NDN_MSFT_STATUS_MASK		0xffff
diff --git a/ndctl/lib/papr.h b/ndctl/lib/papr.h
index 77579396a7bd..4f35bc60017f 100644
--- a/ndctl/lib/papr.h
+++ b/ndctl/lib/papr.h
@@ -8,8 +8,8 @@
 
 /* Wraps a nd_cmd generic header with pdsm header */
 struct nd_pkg_papr {
-	struct nd_cmd_pkg gen;
 	struct nd_pkg_pdsm pdsm;
+	struct nd_cmd_pkg gen;
 };
 
 #endif /* __PAPR_H__ */
diff --git a/ndctl/libndctl-nfit.h b/ndctl/libndctl-nfit.h
index 9ec0db55776d..020dc7384a98 100644
--- a/ndctl/libndctl-nfit.h
+++ b/ndctl/libndctl-nfit.h
@@ -77,13 +77,13 @@ struct nd_cmd_ars_err_inj_stat {
 } __attribute__((packed));
 
 struct nd_cmd_bus {
-	struct nd_cmd_pkg gen;
 	union {
 		struct nd_cmd_ars_err_inj_stat err_inj_stat;
 		struct nd_cmd_ars_err_inj_clr err_inj_clr;
 		struct nd_cmd_ars_err_inj err_inj;
 		struct nd_cmd_translate_spa xlat_spa;
 	};
+	struct nd_cmd_pkg gen;
 };
 
 int ndctl_bus_is_nfit_cmd_supported(struct ndctl_bus *bus, int cmd);
-- 
2.37.3