From: James Smart <jsmart2021@xxxxxxxxx> [ Upstream commit 38503943c89f0bafd9e3742f63f872301d44cbea ] The following kasan bug was called out: BUG: KASAN: slab-out-of-bounds in lpfc_unreg_login+0x7c/0xc0 [lpfc] Read of size 2 at addr ffff889fc7c50a22 by task lpfc_worker_3/6676 ... Call Trace: dump_stack+0x96/0xe0 ? lpfc_unreg_login+0x7c/0xc0 [lpfc] print_address_description.constprop.6+0x1b/0x220 ? lpfc_unreg_login+0x7c/0xc0 [lpfc] ? lpfc_unreg_login+0x7c/0xc0 [lpfc] __kasan_report.cold.9+0x37/0x7c ? lpfc_unreg_login+0x7c/0xc0 [lpfc] kasan_report+0xe/0x20 lpfc_unreg_login+0x7c/0xc0 [lpfc] lpfc_sli_def_mbox_cmpl+0x334/0x430 [lpfc] ... When processing the completion of a "Reg Rpi" login mailbox command in lpfc_sli_def_mbox_cmpl, a call may be made to lpfc_unreg_login. The vpi is extracted from the completing mailbox context and passed as an input for the next. However, the vpi stored in the mailbox command context is an absolute vpi, which for SLI4 represents both base + offset. When used with a non-zero base component, (function id > 0) this results in an out-of-range access beyond the allocated phba->vpi_ids array. Fix by subtracting the function's base value to get an accurate vpi number. Link: https://lore.kernel.org/r/20200322181304.37655-2-jsmart2021@xxxxxxxxx Signed-off-by: James Smart <jsmart2021@xxxxxxxxx> Signed-off-by: Dick Kennedy <dick.kennedy@xxxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/scsi/lpfc/lpfc_sli.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c index cbe808e83f477..1c34dc3355498 100644 --- a/drivers/scsi/lpfc/lpfc_sli.c +++ b/drivers/scsi/lpfc/lpfc_sli.c @@ -2210,6 +2210,8 @@ lpfc_sli_def_mbox_cmpl(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb) !pmb->u.mb.mbxStatus) { rpi = pmb->u.mb.un.varWords[0]; vpi = pmb->u.mb.un.varRegLogin.vpi; + if (phba->sli_rev == LPFC_SLI_REV4) + vpi -= phba->sli4_hba.max_cfg_param.vpi_base; lpfc_unreg_login(phba, vpi, rpi, pmb); pmb->vport = vport; pmb->mbox_cmpl = lpfc_sli_def_mbox_cmpl; -- 2.20.1