[PATCH 2/5] usb: cdnsp: Replace snprintf() with the safer scnprintf() variant
From: Lee Jones
Date: Thu Nov 30 2023 - 05:55:23 EST
There is a general misunderstanding amongst engineers that {v}snprintf()
returns the length of the data *actually* encoded into the destination
array. However, as per the C99 standard {v}snprintf() really returns
the length of the data that *would have been* written if there were
enough space for it. This misunderstanding has led to buffer-overruns
in the past. It's generally considered safer to use the {v}scnprintf()
variants in their place (or even sprintf() in simple cases). So let's
do that.
The uses in this file all seem to assume that data *has been* written!
Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Cc: Pawel Laszczak <pawell@xxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: linux-usb@xxxxxxxxxxxxxxx
Signed-off-by: Lee Jones <lee@xxxxxxxxxx>
---
drivers/usb/cdns3/cdnsp-debug.h | 354 ++++++++++++++++----------------
1 file changed, 177 insertions(+), 177 deletions(-)
diff --git a/drivers/usb/cdns3/cdnsp-debug.h b/drivers/usb/cdns3/cdnsp-debug.h
index ad617b7455b9c..cd138acdcce16 100644
--- a/drivers/usb/cdns3/cdnsp-debug.h
+++ b/drivers/usb/cdns3/cdnsp-debug.h
@@ -187,202 +187,202 @@ static inline const char *cdnsp_decode_trb(char *str, size_t size, u32 field0,
switch (type) {
case TRB_LINK:
- ret = snprintf(str, size,
- "LINK %08x%08x intr %ld type '%s' flags %c:%c:%c:%c",
- field1, field0, GET_INTR_TARGET(field2),
- cdnsp_trb_type_string(type),
- field3 & TRB_IOC ? 'I' : 'i',
- field3 & TRB_CHAIN ? 'C' : 'c',
- field3 & TRB_TC ? 'T' : 't',
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "LINK %08x%08x intr %ld type '%s' flags %c:%c:%c:%c",
+ field1, field0, GET_INTR_TARGET(field2),
+ cdnsp_trb_type_string(type),
+ field3 & TRB_IOC ? 'I' : 'i',
+ field3 & TRB_CHAIN ? 'C' : 'c',
+ field3 & TRB_TC ? 'T' : 't',
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_TRANSFER:
case TRB_COMPLETION:
case TRB_PORT_STATUS:
case TRB_HC_EVENT:
- ret = snprintf(str, size,
- "ep%d%s(%d) type '%s' TRB %08x%08x status '%s'"
- " len %ld slot %ld flags %c:%c",
- ep_num, ep_id % 2 ? "out" : "in",
- TRB_TO_EP_INDEX(field3),
- cdnsp_trb_type_string(type), field1, field0,
- cdnsp_trb_comp_code_string(GET_COMP_CODE(field2)),
- EVENT_TRB_LEN(field2), TRB_TO_SLOT_ID(field3),
- field3 & EVENT_DATA ? 'E' : 'e',
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "ep%d%s(%d) type '%s' TRB %08x%08x status '%s'"
+ " len %ld slot %ld flags %c:%c",
+ ep_num, ep_id % 2 ? "out" : "in",
+ TRB_TO_EP_INDEX(field3),
+ cdnsp_trb_type_string(type), field1, field0,
+ cdnsp_trb_comp_code_string(GET_COMP_CODE(field2)),
+ EVENT_TRB_LEN(field2), TRB_TO_SLOT_ID(field3),
+ field3 & EVENT_DATA ? 'E' : 'e',
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_MFINDEX_WRAP:
- ret = snprintf(str, size, "%s: flags %c",
- cdnsp_trb_type_string(type),
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size, "%s: flags %c",
+ cdnsp_trb_type_string(type),
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_SETUP:
- ret = snprintf(str, size,
- "type '%s' bRequestType %02x bRequest %02x "
- "wValue %02x%02x wIndex %02x%02x wLength %d "
- "length %ld TD size %ld intr %ld Setup ID %ld "
- "flags %c:%c:%c",
- cdnsp_trb_type_string(type),
- field0 & 0xff,
- (field0 & 0xff00) >> 8,
- (field0 & 0xff000000) >> 24,
- (field0 & 0xff0000) >> 16,
- (field1 & 0xff00) >> 8,
- field1 & 0xff,
- (field1 & 0xff000000) >> 16 |
- (field1 & 0xff0000) >> 16,
- TRB_LEN(field2), GET_TD_SIZE(field2),
- GET_INTR_TARGET(field2),
- TRB_SETUPID_TO_TYPE(field3),
- field3 & TRB_IDT ? 'D' : 'd',
- field3 & TRB_IOC ? 'I' : 'i',
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "type '%s' bRequestType %02x bRequest %02x "
+ "wValue %02x%02x wIndex %02x%02x wLength %d "
+ "length %ld TD size %ld intr %ld Setup ID %ld "
+ "flags %c:%c:%c",
+ cdnsp_trb_type_string(type),
+ field0 & 0xff,
+ (field0 & 0xff00) >> 8,
+ (field0 & 0xff000000) >> 24,
+ (field0 & 0xff0000) >> 16,
+ (field1 & 0xff00) >> 8,
+ field1 & 0xff,
+ (field1 & 0xff000000) >> 16 |
+ (field1 & 0xff0000) >> 16,
+ TRB_LEN(field2), GET_TD_SIZE(field2),
+ GET_INTR_TARGET(field2),
+ TRB_SETUPID_TO_TYPE(field3),
+ field3 & TRB_IDT ? 'D' : 'd',
+ field3 & TRB_IOC ? 'I' : 'i',
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_DATA:
- ret = snprintf(str, size,
- "type '%s' Buffer %08x%08x length %ld TD size %ld "
- "intr %ld flags %c:%c:%c:%c:%c:%c:%c",
- cdnsp_trb_type_string(type),
- field1, field0, TRB_LEN(field2),
- GET_TD_SIZE(field2),
- GET_INTR_TARGET(field2),
- field3 & TRB_IDT ? 'D' : 'i',
- field3 & TRB_IOC ? 'I' : 'i',
- field3 & TRB_CHAIN ? 'C' : 'c',
- field3 & TRB_NO_SNOOP ? 'S' : 's',
- field3 & TRB_ISP ? 'I' : 'i',
- field3 & TRB_ENT ? 'E' : 'e',
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "type '%s' Buffer %08x%08x length %ld TD size %ld "
+ "intr %ld flags %c:%c:%c:%c:%c:%c:%c",
+ cdnsp_trb_type_string(type),
+ field1, field0, TRB_LEN(field2),
+ GET_TD_SIZE(field2),
+ GET_INTR_TARGET(field2),
+ field3 & TRB_IDT ? 'D' : 'i',
+ field3 & TRB_IOC ? 'I' : 'i',
+ field3 & TRB_CHAIN ? 'C' : 'c',
+ field3 & TRB_NO_SNOOP ? 'S' : 's',
+ field3 & TRB_ISP ? 'I' : 'i',
+ field3 & TRB_ENT ? 'E' : 'e',
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_STATUS:
- ret = snprintf(str, size,
- "Buffer %08x%08x length %ld TD size %ld intr"
- "%ld type '%s' flags %c:%c:%c:%c",
- field1, field0, TRB_LEN(field2),
- GET_TD_SIZE(field2),
- GET_INTR_TARGET(field2),
- cdnsp_trb_type_string(type),
- field3 & TRB_IOC ? 'I' : 'i',
- field3 & TRB_CHAIN ? 'C' : 'c',
- field3 & TRB_ENT ? 'E' : 'e',
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "Buffer %08x%08x length %ld TD size %ld intr"
+ "%ld type '%s' flags %c:%c:%c:%c",
+ field1, field0, TRB_LEN(field2),
+ GET_TD_SIZE(field2),
+ GET_INTR_TARGET(field2),
+ cdnsp_trb_type_string(type),
+ field3 & TRB_IOC ? 'I' : 'i',
+ field3 & TRB_CHAIN ? 'C' : 'c',
+ field3 & TRB_ENT ? 'E' : 'e',
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_NORMAL:
case TRB_ISOC:
case TRB_EVENT_DATA:
case TRB_TR_NOOP:
- ret = snprintf(str, size,
- "type '%s' Buffer %08x%08x length %ld "
- "TD size %ld intr %ld "
- "flags %c:%c:%c:%c:%c:%c:%c:%c:%c",
- cdnsp_trb_type_string(type),
- field1, field0, TRB_LEN(field2),
- GET_TD_SIZE(field2),
- GET_INTR_TARGET(field2),
- field3 & TRB_BEI ? 'B' : 'b',
- field3 & TRB_IDT ? 'T' : 't',
- field3 & TRB_IOC ? 'I' : 'i',
- field3 & TRB_CHAIN ? 'C' : 'c',
- field3 & TRB_NO_SNOOP ? 'S' : 's',
- field3 & TRB_ISP ? 'I' : 'i',
- field3 & TRB_ENT ? 'E' : 'e',
- field3 & TRB_CYCLE ? 'C' : 'c',
- !(field3 & TRB_EVENT_INVALIDATE) ? 'V' : 'v');
+ ret = scnprintf(str, size,
+ "type '%s' Buffer %08x%08x length %ld "
+ "TD size %ld intr %ld "
+ "flags %c:%c:%c:%c:%c:%c:%c:%c:%c",
+ cdnsp_trb_type_string(type),
+ field1, field0, TRB_LEN(field2),
+ GET_TD_SIZE(field2),
+ GET_INTR_TARGET(field2),
+ field3 & TRB_BEI ? 'B' : 'b',
+ field3 & TRB_IDT ? 'T' : 't',
+ field3 & TRB_IOC ? 'I' : 'i',
+ field3 & TRB_CHAIN ? 'C' : 'c',
+ field3 & TRB_NO_SNOOP ? 'S' : 's',
+ field3 & TRB_ISP ? 'I' : 'i',
+ field3 & TRB_ENT ? 'E' : 'e',
+ field3 & TRB_CYCLE ? 'C' : 'c',
+ !(field3 & TRB_EVENT_INVALIDATE) ? 'V' : 'v');
break;
case TRB_CMD_NOOP:
case TRB_ENABLE_SLOT:
- ret = snprintf(str, size, "%s: flags %c",
- cdnsp_trb_type_string(type),
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size, "%s: flags %c",
+ cdnsp_trb_type_string(type),
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_DISABLE_SLOT:
- ret = snprintf(str, size, "%s: slot %ld flags %c",
- cdnsp_trb_type_string(type),
- TRB_TO_SLOT_ID(field3),
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size, "%s: slot %ld flags %c",
+ cdnsp_trb_type_string(type),
+ TRB_TO_SLOT_ID(field3),
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_ADDR_DEV:
- ret = snprintf(str, size,
- "%s: ctx %08x%08x slot %ld flags %c:%c",
- cdnsp_trb_type_string(type), field1, field0,
- TRB_TO_SLOT_ID(field3),
- field3 & TRB_BSR ? 'B' : 'b',
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "%s: ctx %08x%08x slot %ld flags %c:%c",
+ cdnsp_trb_type_string(type), field1, field0,
+ TRB_TO_SLOT_ID(field3),
+ field3 & TRB_BSR ? 'B' : 'b',
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_CONFIG_EP:
- ret = snprintf(str, size,
- "%s: ctx %08x%08x slot %ld flags %c:%c",
- cdnsp_trb_type_string(type), field1, field0,
- TRB_TO_SLOT_ID(field3),
- field3 & TRB_DC ? 'D' : 'd',
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "%s: ctx %08x%08x slot %ld flags %c:%c",
+ cdnsp_trb_type_string(type), field1, field0,
+ TRB_TO_SLOT_ID(field3),
+ field3 & TRB_DC ? 'D' : 'd',
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_EVAL_CONTEXT:
- ret = snprintf(str, size,
- "%s: ctx %08x%08x slot %ld flags %c",
- cdnsp_trb_type_string(type), field1, field0,
- TRB_TO_SLOT_ID(field3),
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "%s: ctx %08x%08x slot %ld flags %c",
+ cdnsp_trb_type_string(type), field1, field0,
+ TRB_TO_SLOT_ID(field3),
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_RESET_EP:
case TRB_HALT_ENDPOINT:
- ret = snprintf(str, size,
- "%s: ep%d%s(%d) ctx %08x%08x slot %ld flags %c",
- cdnsp_trb_type_string(type),
- ep_num, ep_id % 2 ? "out" : "in",
- TRB_TO_EP_INDEX(field3), field1, field0,
- TRB_TO_SLOT_ID(field3),
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "%s: ep%d%s(%d) ctx %08x%08x slot %ld flags %c",
+ cdnsp_trb_type_string(type),
+ ep_num, ep_id % 2 ? "out" : "in",
+ TRB_TO_EP_INDEX(field3), field1, field0,
+ TRB_TO_SLOT_ID(field3),
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_STOP_RING:
- ret = snprintf(str, size,
- "%s: ep%d%s(%d) slot %ld sp %d flags %c",
- cdnsp_trb_type_string(type),
- ep_num, ep_id % 2 ? "out" : "in",
- TRB_TO_EP_INDEX(field3),
- TRB_TO_SLOT_ID(field3),
- TRB_TO_SUSPEND_PORT(field3),
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "%s: ep%d%s(%d) slot %ld sp %d flags %c",
+ cdnsp_trb_type_string(type),
+ ep_num, ep_id % 2 ? "out" : "in",
+ TRB_TO_EP_INDEX(field3),
+ TRB_TO_SLOT_ID(field3),
+ TRB_TO_SUSPEND_PORT(field3),
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_SET_DEQ:
- ret = snprintf(str, size,
- "%s: ep%d%s(%d) deq %08x%08x stream %ld slot %ld flags %c",
- cdnsp_trb_type_string(type),
- ep_num, ep_id % 2 ? "out" : "in",
- TRB_TO_EP_INDEX(field3), field1, field0,
- TRB_TO_STREAM_ID(field2),
- TRB_TO_SLOT_ID(field3),
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "%s: ep%d%s(%d) deq %08x%08x stream %ld slot %ld flags %c",
+ cdnsp_trb_type_string(type),
+ ep_num, ep_id % 2 ? "out" : "in",
+ TRB_TO_EP_INDEX(field3), field1, field0,
+ TRB_TO_STREAM_ID(field2),
+ TRB_TO_SLOT_ID(field3),
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_RESET_DEV:
- ret = snprintf(str, size, "%s: slot %ld flags %c",
- cdnsp_trb_type_string(type),
- TRB_TO_SLOT_ID(field3),
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size, "%s: slot %ld flags %c",
+ cdnsp_trb_type_string(type),
+ TRB_TO_SLOT_ID(field3),
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
case TRB_ENDPOINT_NRDY:
temp = TRB_TO_HOST_STREAM(field2);
- ret = snprintf(str, size,
- "%s: ep%d%s(%d) H_SID %x%s%s D_SID %lx flags %c:%c",
- cdnsp_trb_type_string(type),
- ep_num, ep_id % 2 ? "out" : "in",
- TRB_TO_EP_INDEX(field3), temp,
- temp == STREAM_PRIME_ACK ? "(PRIME)" : "",
- temp == STREAM_REJECTED ? "(REJECTED)" : "",
- TRB_TO_DEV_STREAM(field0),
- field3 & TRB_STAT ? 'S' : 's',
- field3 & TRB_CYCLE ? 'C' : 'c');
+ ret = scnprintf(str, size,
+ "%s: ep%d%s(%d) H_SID %x%s%s D_SID %lx flags %c:%c",
+ cdnsp_trb_type_string(type),
+ ep_num, ep_id % 2 ? "out" : "in",
+ TRB_TO_EP_INDEX(field3), temp,
+ temp == STREAM_PRIME_ACK ? "(PRIME)" : "",
+ temp == STREAM_REJECTED ? "(REJECTED)" : "",
+ TRB_TO_DEV_STREAM(field0),
+ field3 & TRB_STAT ? 'S' : 's',
+ field3 & TRB_CYCLE ? 'C' : 'c');
break;
default:
- ret = snprintf(str, size,
- "type '%s' -> raw %08x %08x %08x %08x",
- cdnsp_trb_type_string(type),
- field0, field1, field2, field3);
+ ret = scnprintf(str, size,
+ "type '%s' -> raw %08x %08x %08x %08x",
+ cdnsp_trb_type_string(type),
+ field0, field1, field2, field3);
}
- if (ret >= size)
- pr_info("CDNSP: buffer overflowed.\n");
+ if (ret == size - 1)
+ pr_info("CDNSP: buffer may be truncated.\n");
return str;
}
@@ -465,32 +465,32 @@ static inline const char *cdnsp_decode_portsc(char *str, size_t size,
{
int ret;
- ret = snprintf(str, size, "%s %s %s Link:%s PortSpeed:%d ",
- portsc & PORT_POWER ? "Powered" : "Powered-off",
- portsc & PORT_CONNECT ? "Connected" : "Not-connected",
- portsc & PORT_PED ? "Enabled" : "Disabled",
- cdnsp_portsc_link_state_string(portsc),
- DEV_PORT_SPEED(portsc));
+ ret = scnprintf(str, size, "%s %s %s Link:%s PortSpeed:%d ",
+ portsc & PORT_POWER ? "Powered" : "Powered-off",
+ portsc & PORT_CONNECT ? "Connected" : "Not-connected",
+ portsc & PORT_PED ? "Enabled" : "Disabled",
+ cdnsp_portsc_link_state_string(portsc),
+ DEV_PORT_SPEED(portsc));
if (portsc & PORT_RESET)
- ret += snprintf(str + ret, size - ret, "In-Reset ");
+ ret += scnprintf(str + ret, size - ret, "In-Reset ");
- ret += snprintf(str + ret, size - ret, "Change: ");
+ ret += scnprintf(str + ret, size - ret, "Change: ");
if (portsc & PORT_CSC)
- ret += snprintf(str + ret, size - ret, "CSC ");
+ ret += scnprintf(str + ret, size - ret, "CSC ");
if (portsc & PORT_WRC)
- ret += snprintf(str + ret, size - ret, "WRC ");
+ ret += scnprintf(str + ret, size - ret, "WRC ");
if (portsc & PORT_RC)
- ret += snprintf(str + ret, size - ret, "PRC ");
+ ret += scnprintf(str + ret, size - ret, "PRC ");
if (portsc & PORT_PLC)
- ret += snprintf(str + ret, size - ret, "PLC ");
+ ret += scnprintf(str + ret, size - ret, "PLC ");
if (portsc & PORT_CEC)
- ret += snprintf(str + ret, size - ret, "CEC ");
- ret += snprintf(str + ret, size - ret, "Wake: ");
+ ret += scnprintf(str + ret, size - ret, "CEC ");
+ ret += scnprintf(str + ret, size - ret, "Wake: ");
if (portsc & PORT_WKCONN_E)
- ret += snprintf(str + ret, size - ret, "WCE ");
+ ret += scnprintf(str + ret, size - ret, "WCE ");
if (portsc & PORT_WKDISC_E)
- ret += snprintf(str + ret, size - ret, "WDE ");
+ ret += scnprintf(str + ret, size - ret, "WDE ");
return str;
}
@@ -562,20 +562,20 @@ static inline const char *cdnsp_decode_ep_context(char *str, size_t size,
avg = EP_AVG_TRB_LENGTH(tx_info);
- ret = snprintf(str, size, "State %s mult %d max P. Streams %d %s",
- cdnsp_ep_state_string(ep_state), mult,
- max_pstr, lsa ? "LSA " : "");
+ ret = scnprintf(str, size, "State %s mult %d max P. Streams %d %s",
+ cdnsp_ep_state_string(ep_state), mult,
+ max_pstr, lsa ? "LSA " : "");
- ret += snprintf(str + ret, size - ret,
- "interval %d us max ESIT payload %d CErr %d ",
- (1 << interval) * 125, esit, cerr);
+ ret += scnprintf(str + ret, size - ret,
+ "interval %d us max ESIT payload %d CErr %d ",
+ (1 << interval) * 125, esit, cerr);
- ret += snprintf(str + ret, size - ret,
- "Type %s %sburst %d maxp %d deq %016llx ",
- cdnsp_ep_type_string(ep_type), hid ? "HID" : "",
- burst, maxp, deq);
+ ret += scnprintf(str + ret, size - ret,
+ "Type %s %sburst %d maxp %d deq %016llx ",
+ cdnsp_ep_type_string(ep_type), hid ? "HID" : "",
+ burst, maxp, deq);
- ret += snprintf(str + ret, size - ret, "avg trb len %d", avg);
+ ret += scnprintf(str + ret, size - ret, "avg trb len %d", avg);
return str;
}
--
2.43.0.rc1.413.gea7ed67945-goog