From: "Gustavo A. R. Silva" <gustavoars@kernel.org> mainline inclusion from mainline-v6.10-rc1 commit 9748dbc9f26541d35c4231348c64499bf7a19735 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IC914B Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- -Wflex-array-member-not-at-end is coming in GCC-14, and we are getting ready to enable it globally. There are currently a couple of objects in `struct smc_clc_msg_proposal_area` that contain a couple of flexible structures: struct smc_clc_msg_proposal_area { ... struct smc_clc_v2_extension pclc_v2_ext; ... struct smc_clc_smcd_v2_extension pclc_smcd_v2_ext; ... }; So, in order to avoid ending up with a couple of flexible-array members in the middle of a struct, we use the `struct_group_tagged()` helper to separate the flexible array from the rest of the members in the flexible structure: struct smc_clc_smcd_v2_extension { struct_group_tagged(smc_clc_smcd_v2_extension_fixed, fixed, u8 system_eid[SMC_MAX_EID_LEN]; u8 reserved[16]; ); struct smc_clc_smcd_gid_chid gidchid[]; }; With the change described above, we now declare objects of the type of the tagged struct without embedding flexible arrays in the middle of another struct: struct smc_clc_msg_proposal_area { ... struct smc_clc_v2_extension_fixed pclc_v2_ext; ... struct smc_clc_smcd_v2_extension_fixed pclc_smcd_v2_ext; ... }; We also use `container_of()` when we need to retrieve a pointer to the flexible structures. So, with these changes, fix the following warnings: In file included from net/smc/af_smc.c:42: net/smc/smc_clc.h:186:49: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] 186 | struct smc_clc_v2_extension pclc_v2_ext; | ^~~~~~~~~~~ net/smc/smc_clc.h:188:49: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] 188 | struct smc_clc_smcd_v2_extension pclc_smcd_v2_ext; | ^~~~~~~~~~~~~~~~ Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-by: Wen Gu <guwen@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Wang Liang <wangliang74@huawei.com> --- net/smc/smc_clc.c | 6 ++++-- net/smc/smc_clc.h | 26 ++++++++++++++++---------- 2 files changed, 20 insertions(+), 12 deletions(-) diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c index 6c8c183c9d46..1e7bdaff78a4 100644 --- a/net/smc/smc_clc.c +++ b/net/smc/smc_clc.c @@ -856,8 +856,10 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini) pclc_smcd = &pclc->pclc_smcd; pclc_prfx = &pclc->pclc_prfx; ipv6_prfx = pclc->pclc_prfx_ipv6; - v2_ext = &pclc->pclc_v2_ext; - smcd_v2_ext = &pclc->pclc_smcd_v2_ext; + v2_ext = container_of(&pclc->pclc_v2_ext, + struct smc_clc_v2_extension, fixed); + smcd_v2_ext = container_of(&pclc->pclc_smcd_v2_ext, + struct smc_clc_smcd_v2_extension, fixed); gidchids = pclc->pclc_gidchids; trl = &pclc->pclc_trl; diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h index 090e920a0938..d7a829b8b6f3 100644 --- a/net/smc/smc_clc.h +++ b/net/smc/smc_clc.h @@ -134,12 +134,15 @@ struct smc_clc_smcd_gid_chid { */ struct smc_clc_v2_extension { - struct smc_clnt_opts_area_hdr hdr; - u8 roce[16]; /* RoCEv2 GID */ - u8 max_conns; - u8 max_links; - __be16 feature_mask; - u8 reserved[12]; + /* New members must be added within the struct_group() macro below. */ + struct_group_tagged(smc_clc_v2_extension_fixed, fixed, + struct smc_clnt_opts_area_hdr hdr; + u8 roce[16]; /* RoCEv2 GID */ + u8 max_conns; + u8 max_links; + __be16 feature_mask; + u8 reserved[12]; + ); u8 user_eids[][SMC_MAX_EID_LEN]; }; @@ -159,8 +162,11 @@ struct smc_clc_msg_smcd { /* SMC-D GID information */ }; struct smc_clc_smcd_v2_extension { - u8 system_eid[SMC_MAX_EID_LEN]; - u8 reserved[16]; + /* New members must be added within the struct_group() macro below. */ + struct_group_tagged(smc_clc_smcd_v2_extension_fixed, fixed, + u8 system_eid[SMC_MAX_EID_LEN]; + u8 reserved[16]; + ); struct smc_clc_smcd_gid_chid gidchid[]; }; @@ -183,9 +189,9 @@ struct smc_clc_msg_proposal_area { struct smc_clc_msg_smcd pclc_smcd; struct smc_clc_msg_proposal_prefix pclc_prfx; struct smc_clc_ipv6_prefix pclc_prfx_ipv6[SMC_CLC_MAX_V6_PREFIX]; - struct smc_clc_v2_extension pclc_v2_ext; + struct smc_clc_v2_extension_fixed pclc_v2_ext; u8 user_eids[SMC_CLC_MAX_UEID][SMC_MAX_EID_LEN]; - struct smc_clc_smcd_v2_extension pclc_smcd_v2_ext; + struct smc_clc_smcd_v2_extension_fixed pclc_smcd_v2_ext; struct smc_clc_smcd_gid_chid pclc_gidchids[SMCD_CLC_MAX_V2_GID_ENTRIES]; struct smc_clc_msg_trail pclc_trl; -- 2.34.1