| Message ID | 99e06733f5f35c6cd62e05f530b93107bfd03362.1684358315.git.gustavoars@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | scsi: lpfc: Replace one-element array with flexible-array member | expand |
On Wed, May 17, 2023 at 04:01:47PM -0700, Kees Cook wrote: > On Wed, May 17, 2023 at 03:23:01PM -0600, Gustavo A. R. Silva wrote: > > Prefer struct_size() over open-coded versions of idiom: > > > > sizeof(struct-with-flex-array) + sizeof(typeof-flex-array-elements) * count > > > > where count is the max number of items the flexible array is supposed to > > contain. > > > > Link: https://github.com/KSPP/linux/issues/160 > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> > > --- > > drivers/scsi/lpfc/lpfc_ct.c | 6 ++---- > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/scsi/lpfc/lpfc_ct.c b/drivers/scsi/lpfc/lpfc_ct.c > > index e880d127d7f5..3b95c56023bf 100644 > > --- a/drivers/scsi/lpfc/lpfc_ct.c > > +++ b/drivers/scsi/lpfc/lpfc_ct.c > > @@ -3748,8 +3748,7 @@ lpfc_vmid_cmd(struct lpfc_vport *vport, > > rap->obj[0].entity_id_len = vmid->vmid_len; > > memcpy(rap->obj[0].entity_id, vmid->host_vmid, vmid->vmid_len); > > size = RAPP_IDENT_OFFSET + > > - sizeof(struct lpfc_vmid_rapp_ident_list) + > > - sizeof(struct entity_id_object); > > + struct_size(rap, obj, rap->no_of_objects); > > Has rap->no_of_objects always been "1"? (i.e. there was a prior > multiplication here before... Mmh.. not sure what multiplication you are talking about. I based these changes on the fact that rap->no_of_objects is set to cpu_to_be32(1); for both instances. It doesn't show up in the context of the patch, so here you go: 3747 rap->no_of_objects = cpu_to_be32(1); 3748 rap->obj[0].entity_id_len = vmid->vmid_len; 3749 memcpy(rap->obj[0].entity_id, vmid->host_vmid, vmid->vmid_len); 3750 size = RAPP_IDENT_OFFSET + 3751 sizeof(struct lpfc_vmid_rapp_ident_list) + 3752 sizeof(struct entity_id_object); -- Gustavo
On Tue, May 23, 2023 at 08:41:59AM -0600, Gustavo A. R. Silva wrote: > On Wed, May 17, 2023 at 04:01:47PM -0700, Kees Cook wrote: > > On Wed, May 17, 2023 at 03:23:01PM -0600, Gustavo A. R. Silva wrote: > > > Prefer struct_size() over open-coded versions of idiom: > > > > > > sizeof(struct-with-flex-array) + sizeof(typeof-flex-array-elements) * count > > > > > > where count is the max number of items the flexible array is supposed to > > > contain. > > > > > > Link: https://github.com/KSPP/linux/issues/160 > > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> > > > --- > > > drivers/scsi/lpfc/lpfc_ct.c | 6 ++---- > > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > > > diff --git a/drivers/scsi/lpfc/lpfc_ct.c b/drivers/scsi/lpfc/lpfc_ct.c > > > index e880d127d7f5..3b95c56023bf 100644 > > > --- a/drivers/scsi/lpfc/lpfc_ct.c > > > +++ b/drivers/scsi/lpfc/lpfc_ct.c > > > @@ -3748,8 +3748,7 @@ lpfc_vmid_cmd(struct lpfc_vport *vport, > > > rap->obj[0].entity_id_len = vmid->vmid_len; > > > memcpy(rap->obj[0].entity_id, vmid->host_vmid, vmid->vmid_len); > > > size = RAPP_IDENT_OFFSET + > > > - sizeof(struct lpfc_vmid_rapp_ident_list) + > > > - sizeof(struct entity_id_object); > > > + struct_size(rap, obj, rap->no_of_objects); > > > > Has rap->no_of_objects always been "1"? (i.e. there was a prior > > multiplication here before... > > Mmh.. not sure what multiplication you are talking about. I based these > changes on the fact that rap->no_of_objects is set to cpu_to_be32(1); > for both instances. It doesn't show up in the context of the patch, so > here you go: > > 3747 rap->no_of_objects = cpu_to_be32(1); Ah-ha! So, yeah, this patch is bad then, since no_of_objects will be a big-endian "1". This change: + struct_size(rap, obj, rap->no_of_objects); needs to explicitly be: + struct_size(rap, obj, 1); Or, alternatively, just drop the patch entirely.
diff --git a/drivers/scsi/lpfc/lpfc_ct.c b/drivers/scsi/lpfc/lpfc_ct.c index e880d127d7f5..3b95c56023bf 100644 --- a/drivers/scsi/lpfc/lpfc_ct.c +++ b/drivers/scsi/lpfc/lpfc_ct.c @@ -3748,8 +3748,7 @@ lpfc_vmid_cmd(struct lpfc_vport *vport, rap->obj[0].entity_id_len = vmid->vmid_len; memcpy(rap->obj[0].entity_id, vmid->host_vmid, vmid->vmid_len); size = RAPP_IDENT_OFFSET + - sizeof(struct lpfc_vmid_rapp_ident_list) + - sizeof(struct entity_id_object); + struct_size(rap, obj, rap->no_of_objects); retry = 1; break; @@ -3768,8 +3767,7 @@ lpfc_vmid_cmd(struct lpfc_vport *vport, dap->obj[0].entity_id_len = vmid->vmid_len; memcpy(dap->obj[0].entity_id, vmid->host_vmid, vmid->vmid_len); size = DAPP_IDENT_OFFSET + - sizeof(struct lpfc_vmid_dapp_ident_list) + - sizeof(struct entity_id_object); + struct_size(dap, obj, dap->no_of_objects); write_lock(&vport->vmid_lock); vmid->flag &= ~LPFC_VMID_REGISTERED; write_unlock(&vport->vmid_lock);
Prefer struct_size() over open-coded versions of idiom: sizeof(struct-with-flex-array) + sizeof(typeof-flex-array-elements) * count where count is the max number of items the flexible array is supposed to contain. Link: https://github.com/KSPP/linux/issues/160 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- drivers/scsi/lpfc/lpfc_ct.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)