| Message ID | 20230106053153.never.999-kees@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | scsi: megaraid_sas: Add flexible array member for SGLs | expand |
On Thu, 5 Jan 2023, Kees Cook wrote: > struct MPI2_RAID_SCSI_IO_REQUEST ends with a single SGL, but expects to > copy multiple. Add a flexible array member so the compiler can reason > about the size of the memcpy(). This will avoid the run-time false > positive warning: > > memcpy: detected field-spanning write (size 128) of single field "&r1_cmd->io_request->SGL" at drivers/scsi/megaraid/megaraid_sas_fusion.c:3326 (size 16) > > This change results in no binary output differences. > > Reported-by: Holger Kiehl <Holger.Kiehl@dwd.de> > Link: https://lore.kernel.org/all/88de8faa-56c4-693d-2d3-67152ee72057@diagnostix.dwd.de/ > Cc: Kashyap Desai <kashyap.desai@broadcom.com> > Cc: Sumit Saxena <sumit.saxena@broadcom.com> > Cc: Shivasharan S <shivasharan.srikanteshwara@broadcom.com> > Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> > Cc: "Martin K. Petersen" <martin.petersen@oracle.com> > Cc: megaraidlinux.pdl@broadcom.com > Cc: linux-scsi@vger.kernel.org > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > Holger, are you able to test this change? I expect it should do the > trick, but I don't have the hardware. > Yes, that does work. I no longer see 'memcpy: detected field-spanning write (size 128)'. Tested this on 6.1.4-rc1. Did not see any other regression. Regards, Holger
Kees, > struct MPI2_RAID_SCSI_IO_REQUEST ends with a single SGL, but expects > to copy multiple. Add a flexible array member so the compiler can > reason about the size of the memcpy(). This will avoid the run-time > false positive warning: Applied to 6.3/scsi-staging, thanks!
On Thu, 05 Jan 2023 21:32:00 -0800, Kees Cook wrote: > struct MPI2_RAID_SCSI_IO_REQUEST ends with a single SGL, but expects to > copy multiple. Add a flexible array member so the compiler can reason > about the size of the memcpy(). This will avoid the run-time false > positive warning: > > memcpy: detected field-spanning write (size 128) of single field "&r1_cmd->io_request->SGL" at drivers/scsi/megaraid/megaraid_sas_fusion.c:3326 (size 16) > > [...] Applied to 6.3/scsi-queue, thanks! [1/1] scsi: megaraid_sas: Add flexible array member for SGLs https://git.kernel.org/mkp/scsi/c/a9a3629592ab
diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c index fe70f8f11435..6597e118c805 100644 --- a/drivers/scsi/megaraid/megaraid_sas_fusion.c +++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c @@ -3323,7 +3323,7 @@ static void megasas_prepare_secondRaid1_IO(struct megasas_instance *instance, /* copy the io request frame as well as 8 SGEs data for r1 command*/ memcpy(r1_cmd->io_request, cmd->io_request, (sizeof(struct MPI2_RAID_SCSI_IO_REQUEST))); - memcpy(&r1_cmd->io_request->SGL, &cmd->io_request->SGL, + memcpy(r1_cmd->io_request->SGLs, cmd->io_request->SGLs, (fusion->max_sge_in_main_msg * sizeof(union MPI2_SGE_IO_UNION))); /*sense buffer is different for r1 command*/ r1_cmd->io_request->SenseBufferLowAddress = diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.h b/drivers/scsi/megaraid/megaraid_sas_fusion.h index 49e9a9048ee7..b677d80e5874 100644 --- a/drivers/scsi/megaraid/megaraid_sas_fusion.h +++ b/drivers/scsi/megaraid/megaraid_sas_fusion.h @@ -526,7 +526,10 @@ struct MPI2_RAID_SCSI_IO_REQUEST { __le32 Control; /* 0x3C */ union MPI2_SCSI_IO_CDB_UNION CDB; /* 0x40 */ union RAID_CONTEXT_UNION RaidContext; /* 0x60 */ - union MPI2_SGE_IO_UNION SGL; /* 0x80 */ + union { + union MPI2_SGE_IO_UNION SGL; /* 0x80 */ + DECLARE_FLEX_ARRAY(union MPI2_SGE_IO_UNION, SGLs); + }; }; /*
struct MPI2_RAID_SCSI_IO_REQUEST ends with a single SGL, but expects to copy multiple. Add a flexible array member so the compiler can reason about the size of the memcpy(). This will avoid the run-time false positive warning: memcpy: detected field-spanning write (size 128) of single field "&r1_cmd->io_request->SGL" at drivers/scsi/megaraid/megaraid_sas_fusion.c:3326 (size 16) This change results in no binary output differences. Reported-by: Holger Kiehl <Holger.Kiehl@dwd.de> Link: https://lore.kernel.org/all/88de8faa-56c4-693d-2d3-67152ee72057@diagnostix.dwd.de/ Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Sumit Saxena <sumit.saxena@broadcom.com> Cc: Shivasharan S <shivasharan.srikanteshwara@broadcom.com> Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: megaraidlinux.pdl@broadcom.com Cc: linux-scsi@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> --- Holger, are you able to test this change? I expect it should do the trick, but I don't have the hardware. --- drivers/scsi/megaraid/megaraid_sas_fusion.c | 2 +- drivers/scsi/megaraid/megaraid_sas_fusion.h | 5 ++++- 2 files changed, 5 insertions(+), 2 deletions(-)