Re: [dpdk-dev] [PATCH 3/4] net/ice/base: fix build with gcc11

["Wang, Haiyue" <haiyue.wang@intel.com>]

> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Ferruh Yigit
> Sent: Monday, May 10, 2021 23:03
> To: Yang, Qiming <qiming.yang@intel.com>; Zhang, Qi Z <qi.z.zhang@intel.com>; Stillwell Jr, Paul M
> <paul.m.stillwell.jr@intel.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>; Rong, Leyi <leyi.rong@intel.com>;
> Shukla, Shivanshu <shivanshu.shukla@intel.com>
> Cc: Yigit, Ferruh <ferruh.yigit@intel.com>; dev@dpdk.org; stable@dpdk.org; Kevin Traynor
> <ktraynor@redhat.com>; Ajit Khaparde <ajit.khaparde@broadcom.com>
> Subject: [dpdk-dev] [PATCH 3/4] net/ice/base: fix build with gcc11
>
> Reproduced with '--buildtype=debugoptimized' config,
> compiler version: gcc (GCC) 12.0.0 20210509 (experimental)
>
> There are multiple build errors, like:
> ../drivers/net/ice/base/ice_switch.c: In function ‘ice_add_marker_act’:
> ../drivers/net/ice/base/ice_switch.c:3727:15:
>       warning: array subscript ‘struct ice_aqc_sw_rules_elem[0]’
>       is partly outside array bounds of ‘unsigned char[52]’
>       [-Warray-bounds]
>  3727 |         lg_act->type = CPU_TO_LE16(ICE_AQC_SW_RULES_T_LG_ACT);
>       |               ^~
> In file included from ../drivers/net/ice/base/ice_type.h:52,
>                  from ../drivers/net/ice/base/ice_common.h:8,
>                  from ../drivers/net/ice/base/ice_switch.h:8,
>                  from ../drivers/net/ice/base/ice_switch.c:5:
> ../drivers/net/ice/base/ice_osdep.h:209:29:
>       note: referencing an object of size 52 allocated by ‘rte_zmalloc’
>   209 | #define ice_malloc(h, s)    rte_zmalloc(NULL, s, 0)
>       |                             ^~~~~~~~~~~~~~~~~~~~~~~
> ../drivers/net/ice/base/ice_switch.c:3720:50:
>       note: in expansion of macro ‘ice_malloc’
>   lg_act = (struct ice_aqc_sw_rules_elem *)ice_malloc(hw, rules_size);
>
> These errors are mainly because allocated memory is cast to
> "struct ice_aqc_sw_rules_elem *" but allocated size is less than the size
> of "struct ice_aqc_sw_rules_elem".
>
> "struct ice_aqc_sw_rules_elem" has multiple other structs has unions,
> based on which one is used allocated memory being less than the size of
> "struct ice_aqc_sw_rules_elem" is logically correct but compiler is
> complaining about it.
>
> As a solution making sure allocated memory size is at least size of
> "struct ice_aqc_sw_rules_elem".
> The function to use the struct is 'ice_aq_sw_rules()', and it already has
> parameter for size of the rule, allocating more than needed shouldn't
> cause any problem.
>
> Fixes: c7dd15931183 ("net/ice/base: add virtual switch code")
> Fixes: 02acdce2f553 ("net/ice/base: add MAC filter with marker and counter")
> Fixes: f89aa3affa9e ("net/ice/base: support removing advanced rule")
> Cc: stable@dpdk.org
>
> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
> ---
> Cc: paul.m.stillwell.jr@intel.com
> Cc: qi.z.zhang@intel.com
> Cc: leyi.rong@intel.com
> Cc: Kevin Traynor <ktraynor@redhat.com>
> Cc: Ajit Khaparde <ajit.khaparde@broadcom.com>
> ---
>  drivers/net/ice/base/ice_switch.c | 30 +++++++++++++++++++++++-------
>  1 file changed, 23 insertions(+), 7 deletions(-)

GCC bug ?

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98266

Bug 98266 - [11 Regression] bogus array subscript is partly outside array bounds on virtual inheritance



> --
> 2.31.1