On Tue, Sep 11, 2018 at 11:24 AM, Kees Cook <keescook@xxxxxxxxxxxx> wrote: > On Tue, Sep 11, 2018 at 11:05 AM, Laura Abbott <labbott@xxxxxxxxxx> wrote: >> >> There's currently a warning about string overflow with strncat: >> >> drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c: In function 'ibmvscsis_probe': >> drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c:3479:2: error: 'strncat' specified >> bound 64 equals destination size [-Werror=stringop-overflow=] >> strncat(vscsi->eye, vdev->name, MAX_EYE); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> Switch to a single snprintf instead of a strcpy + strcat to handle this >> cleanly. >> >> Signed-off-by: Laura Abbott <labbott@xxxxxxxxxx> > > Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> > > -Kees > >> --- >> v2: Swtich to using snprintf per suggestion of Kees >> --- >> drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c | 3 +-- >> 1 file changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c >> index fac377320158..9305440a00a1 100644 >> --- a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c >> +++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c >> @@ -3474,8 +3474,7 @@ static int ibmvscsis_probe(struct vio_dev *vdev, >> vscsi->dds.window[LOCAL].liobn, >> vscsi->dds.window[REMOTE].liobn); >> >> - strcpy(vscsi->eye, "VSCSI "); >> - strncat(vscsi->eye, vdev->name, MAX_EYE); >> + snprintf(vscsi->eye, sizeof(vscsi->eye), "VSCSI%s", vdev->name); Eek. No, I take it back: Nick Desaulniers has better eyes than me and pointed out that there should be a space after VSCSI. -Kees >> >> vscsi->dds.unit_id = vdev->unit_address; >> strncpy(vscsi->dds.partition_name, partition_name, >> -- >> 2.17.1 >> > > > > -- > Kees Cook > Pixel Security -- Kees Cook Pixel Security