From b13148d91805143aba3e0b4441e760b9bea03b8c Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 11 Jan 2022 17:10:47 +0000 Subject: [PATCH] hw/intc/arm_gicv3_its: Check indexes before use, not after MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In a few places in the ITS command handling functions, we were doing the range-check of an event ID or device ID only after using it as a table index; move the checks to before the uses. This misordering wouldn't have very bad effects because the tables are in guest memory anyway. Signed-off-by: Peter Maydell Reviewed-by: Alex Bennée Message-id: 20220111171048.3545974-13-peter.maydell@linaro.org --- hw/intc/arm_gicv3_its.c | 42 ++++++++++++++++++++++++----------------- 1 file changed, 25 insertions(+), 17 deletions(-) diff --git a/hw/intc/arm_gicv3_its.c b/hw/intc/arm_gicv3_its.c index 985e316eda..ef6c0f55ff 100644 --- a/hw/intc/arm_gicv3_its.c +++ b/hw/intc/arm_gicv3_its.c @@ -255,6 +255,13 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value, eventid = (value & EVENTID_MASK); + if (devid >= s->dt.num_ids) { + qemu_log_mask(LOG_GUEST_ERROR, + "%s: invalid command attributes: devid %d>=%d", + __func__, devid, s->dt.num_ids); + return CMD_CONTINUE; + } + dte = get_dte(s, devid, &res); if (res != MEMTX_OK) { @@ -272,6 +279,14 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value, num_eventids = 1ULL << (FIELD_EX64(dte, DTE, SIZE) + 1); + if (eventid >= num_eventids) { + qemu_log_mask(LOG_GUEST_ERROR, + "%s: invalid command attributes: eventid %d >= %" + PRId64 "\n", + __func__, eventid, num_eventids); + return CMD_CONTINUE; + } + ite_valid = get_ite(s, eventid, dte, &icid, &pIntid, &res); if (res != MEMTX_OK) { return CMD_STALL; @@ -296,20 +311,6 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value, return CMD_CONTINUE; } - if (devid >= s->dt.num_ids) { - qemu_log_mask(LOG_GUEST_ERROR, - "%s: invalid command attributes: devid %d>=%d", - __func__, devid, s->dt.num_ids); - return CMD_CONTINUE; - } - if (eventid >= num_eventids) { - qemu_log_mask(LOG_GUEST_ERROR, - "%s: invalid command attributes: eventid %d >= %" - PRId64 "\n", - __func__, eventid, num_eventids); - return CMD_CONTINUE; - } - /* * Current implementation only supports rdbase == procnum * Hence rdbase physical address is ignored @@ -375,6 +376,13 @@ static ItsCmdResult process_mapti(GICv3ITSState *s, uint64_t value, icid = value & ICID_MASK; + if (devid >= s->dt.num_ids) { + qemu_log_mask(LOG_GUEST_ERROR, + "%s: invalid command attributes: devid %d>=%d", + __func__, devid, s->dt.num_ids); + return CMD_CONTINUE; + } + dte = get_dte(s, devid, &res); if (res != MEMTX_OK) { @@ -384,14 +392,14 @@ static ItsCmdResult process_mapti(GICv3ITSState *s, uint64_t value, num_eventids = 1ULL << (FIELD_EX64(dte, DTE, SIZE) + 1); num_intids = 1ULL << (GICD_TYPER_IDBITS + 1); - if ((devid >= s->dt.num_ids) || (icid >= s->ct.num_ids) + if ((icid >= s->ct.num_ids) || !dte_valid || (eventid >= num_eventids) || (((pIntid < GICV3_LPI_INTID_START) || (pIntid >= num_intids)) && (pIntid != INTID_SPURIOUS))) { qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid command attributes " - "devid %d or icid %d or eventid %d or pIntid %d or" - "unmapped dte %d\n", __func__, devid, icid, eventid, + "icid %d or eventid %d or pIntid %d or" + "unmapped dte %d\n", __func__, icid, eventid, pIntid, dte_valid); /* * in this implementation, in case of error