| Message ID | 20210302152716.GA200887@embeddedor (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [next] net: fddi: skfp: smt: Replace one-element array with flexible-array member | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Guessed tree name to be net-next |
| netdev/subject_prefix | warning | Target tree name not specified in the subject |
| netdev/cc_maintainers | warning | 2 maintainers not CCed: lee.jones@linaro.org penguin-kernel@I-love.SAKURA.ne.jp |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 5 this patch: 5 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 22 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 5 this patch: 5 |
| netdev/header_inline | success | Link |
| netdev/stable | success | Stable not CCed |
diff --git a/drivers/net/fddi/skfp/h/smt.h b/drivers/net/fddi/skfp/h/smt.h index a0dbc0f57a55..751b5bb87a9d 100644 --- a/drivers/net/fddi/skfp/h/smt.h +++ b/drivers/net/fddi/skfp/h/smt.h @@ -764,10 +764,8 @@ struct smt_sif_operation { struct smt_p_setcount setcount ; /* Set Count mandatory */ #endif /* must be last */ - struct smt_p_lem lem[1] ; /* phy lem status */ + struct smt_p_lem lem[]; /* phy lem status */ } ; -#define SIZEOF_SMT_SIF_OPERATION (sizeof(struct smt_sif_operation)- \ - sizeof(struct smt_p_lem)) /* * ECF : echo frame diff --git a/drivers/net/fddi/skfp/smt.c b/drivers/net/fddi/skfp/smt.c index 774a6e3b0a67..6b68a53f1b38 100644 --- a/drivers/net/fddi/skfp/smt.c +++ b/drivers/net/fddi/skfp/smt.c @@ -1063,9 +1063,9 @@ static void smt_send_sif_operation(struct s_smc *smc, struct fddi_addr *dest, #endif if (!(mb = smt_build_frame(smc,SMT_SIF_OPER,SMT_REPLY, - SIZEOF_SMT_SIF_OPERATION+ports*sizeof(struct smt_p_lem)))) + struct_size(sif, lem, ports)))) return ; - sif = smtod(mb, struct smt_sif_operation *) ; + sif = smtod(mb, typeof(sif)); smt_fill_timestamp(smc,&sif->ts) ; /* set time stamp */ smt_fill_mac_status(smc,&sif->status) ; /* set mac status */ smt_fill_mac_counter(smc,&sif->mc) ; /* set mac counter field */
There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. Refactor the code according to the use of flexible-array members in smt_sif_operation structure, instead of one-element arrays. Also, make use of the struct_size() helper instead of the open-coded version to calculate the size of the struct-with-flex-array. Additionally, make use of the typeof operator to properly determine the object type to be passed to macro smtod(). Also, this helps the ongoing efforts to enable -Warray-bounds by fixing the following warnings: CC [M] drivers/net/fddi/skfp/smt.o drivers/net/fddi/skfp/smt.c: In function ‘smt_send_sif_operation’: drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ | ^~~ drivers/net/fddi/skfp/smt.c:1084:30: warning: array subscript 1 is above array bounds of ‘struct smt_p_lem[1]’ [-Warray-bounds] 1084 | smt_fill_lem(smc,&sif->lem[i],i) ; | ~~~~~~~~^~~ In file included from drivers/net/fddi/skfp/h/smc.h:42, from drivers/net/fddi/skfp/smt.c:15: drivers/net/fddi/skfp/h/smt.h:767:19: note: while referencing ‘lem’ 767 | struct smt_p_lem lem[1] ; /* phy lem status */ [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.9/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/79 Link: https://github.com/KSPP/linux/issues/109 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- drivers/net/fddi/skfp/h/smt.h | 4 +--- drivers/net/fddi/skfp/smt.c | 4 ++-- 2 files changed, 3 insertions(+), 5 deletions(-)