bhyve nvme: Fix Controller init error cases

Fuzzing of bhyve uncovered an assertion failure in the NVMe emulation.
Investigation uncovered several corner cases the code did not handle.
This change handles several Controller initialization errors, including
 - bad AQ sizes
 - bad AQ vm_map_gpa
 - doorbell writes prior to RDY
 - doorbell writes to uninitialized queue
 - CSTS.RDY if CFS set

PR:		256317,256319,256320,256322
Reported by:	Cheolwoo Myung <cwmyung@snu.ac.kr>
Reviewed by:	jhb
Differential Revision:	https://reviews.freebsd.org/D35453
This commit is contained in:
Chuck Tuffli 2022-08-14 07:47:34 -07:00
parent 3d3678627c
commit d7d1becad4

View File

@ -398,6 +398,7 @@ static void pci_nvme_io_done(struct blockif_req *, int);
((sts) >> NVME_CSTS_REG_RDY_SHIFT & NVME_CSTS_REG_RDY_MASK)
#define NVME_CSTS_RDY (1 << NVME_CSTS_REG_RDY_SHIFT)
#define NVME_CSTS_CFS (1 << NVME_CSTS_REG_CFS_SHIFT)
/* Completion Queue status word utils */
#define NVME_STATUS_P (1 << NVME_STATUS_P_SHIFT)
@ -1081,30 +1082,61 @@ pci_nvme_reset(struct pci_nvme_softc *sc)
pthread_mutex_unlock(&sc->mtx);
}
static void
static int
pci_nvme_init_controller(struct vmctx *ctx, struct pci_nvme_softc *sc)
{
uint16_t acqs, asqs;
DPRINTF("%s", __func__);
asqs = (sc->regs.aqa & NVME_AQA_REG_ASQS_MASK) + 1;
/*
* NVMe 2.0 states that "enabling a controller while this field is
* cleared to 0h produces undefined results" for both ACQS and
* ASQS. If zero, set CFS and do not become ready.
*/
asqs = ONE_BASED(sc->regs.aqa & NVME_AQA_REG_ASQS_MASK);
if (asqs < 2) {
EPRINTLN("%s: illegal ASQS value %#x (aqa=%#x)", __func__,
asqs - 1, sc->regs.aqa);
sc->regs.csts |= NVME_CSTS_CFS;
return (-1);
}
sc->submit_queues[0].size = asqs;
sc->submit_queues[0].qbase = vm_map_gpa(ctx, sc->regs.asq,
sizeof(struct nvme_command) * asqs);
if (sc->submit_queues[0].qbase == NULL) {
EPRINTLN("%s: ASQ vm_map_gpa(%lx) failed", __func__,
sc->regs.asq);
sc->regs.csts |= NVME_CSTS_CFS;
return (-1);
}
DPRINTF("%s mapping Admin-SQ guest 0x%lx, host: %p",
__func__, sc->regs.asq, sc->submit_queues[0].qbase);
acqs = ((sc->regs.aqa >> NVME_AQA_REG_ACQS_SHIFT) &
NVME_AQA_REG_ACQS_MASK) + 1;
acqs = ONE_BASED((sc->regs.aqa >> NVME_AQA_REG_ACQS_SHIFT) &
NVME_AQA_REG_ACQS_MASK);
if (acqs < 2) {
EPRINTLN("%s: illegal ACQS value %#x (aqa=%#x)", __func__,
acqs - 1, sc->regs.aqa);
sc->regs.csts |= NVME_CSTS_CFS;
return (-1);
}
sc->compl_queues[0].size = acqs;
sc->compl_queues[0].qbase = vm_map_gpa(ctx, sc->regs.acq,
sizeof(struct nvme_completion) * acqs);
if (sc->compl_queues[0].qbase == NULL) {
EPRINTLN("%s: ACQ vm_map_gpa(%lx) failed", __func__,
sc->regs.acq);
sc->regs.csts |= NVME_CSTS_CFS;
return (-1);
}
sc->compl_queues[0].intr_en = NVME_CQ_INTEN;
DPRINTF("%s mapping Admin-CQ guest 0x%lx, host: %p",
__func__, sc->regs.acq, sc->compl_queues[0].qbase);
return (0);
}
static int
@ -2872,6 +2904,12 @@ pci_nvme_write_bar_0(struct vmctx *ctx, struct pci_nvme_softc* sc,
uint64_t idx = belloffset / 8; /* door bell size = 2*int */
int is_sq = (belloffset % 8) < 4;
if ((sc->regs.csts & NVME_CSTS_RDY) == 0) {
WPRINTF("doorbell write prior to RDY (offset=%#lx)\n",
offset);
return;
}
if (belloffset > ((sc->max_queues+1) * 8 - 4)) {
WPRINTF("guest attempted an overflow write offset "
"0x%lx, val 0x%lx in %s",
@ -2879,6 +2917,12 @@ pci_nvme_write_bar_0(struct vmctx *ctx, struct pci_nvme_softc* sc,
return;
}
if (is_sq) {
if (sc->submit_queues[idx].qbase == NULL)
return;
} else if (sc->compl_queues[idx].qbase == NULL)
return;
pci_nvme_handle_doorbell(ctx, sc, idx, is_sq, value);
return;
}
@ -2945,7 +2989,8 @@ pci_nvme_write_bar_0(struct vmctx *ctx, struct pci_nvme_softc* sc,
sc->regs.cc &= ~NVME_CC_NEN_WRITE_MASK;
sc->regs.cc |= ccreg & NVME_CC_NEN_WRITE_MASK;
sc->regs.csts &= ~NVME_CSTS_RDY;
} else if (sc->pending_ios == 0) {
} else if ((sc->pending_ios == 0) &&
!(sc->regs.csts & NVME_CSTS_CFS)) {
sc->regs.csts |= NVME_CSTS_RDY;
}
break;