From patchwork Thu Nov 30 10:54:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lee Jones X-Patchwork-Id: 749457 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3F33B3C076 for ; Thu, 30 Nov 2023 10:55:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CaVZ2p03" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D9C6CC433C7; Thu, 30 Nov 2023 10:55:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701341715; bh=W8jJlgZ5YEkMVFo7GXvQSzyeogzUbP++bKRPuTNNOWw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CaVZ2p039qMYbW4/1hxYB+x9Gy4bRKhvyDsJr7uHxreUuESYlXED0uFuTipBwZRcz m5hkDRSc/5Haa37jdaZdy6oFXYGD5+hqWaKt0YFO+oJ/nEt6/U9OHr1tSbP0xdFPvu GyiDdTEhwjbTXw4FG5bkZotVEIC1VhhKf3RhPd0lh7KxJo+AhkgB2FKyS8lQG3BFmI URBCShZzKzynPSY6iOcE/HCK44bulNxDEZRvb8e3lXlOlMxme7giZlJWdVoGr4kNZG /SWxdgpSwhno5jXdJvPycpKgt2xpHT4wFLKtjjmG9laoDBu/0ZhYO0HfYFnj1fc+D5 fnzN1vv4Gbp9w== From: Lee Jones To: lee@kernel.org Cc: linux-kernel@vger.kernel.org, Pawel Laszczak , Greg Kroah-Hartman , linux-usb@vger.kernel.org Subject: [PATCH 2/5] usb: cdnsp: Replace snprintf() with the safer scnprintf() variant Date: Thu, 30 Nov 2023 10:54:36 +0000 Message-ID: <20231130105459.3208986-3-lee@kernel.org> X-Mailer: git-send-email 2.43.0.rc1.413.gea7ed67945-goog In-Reply-To: <20231130105459.3208986-1-lee@kernel.org> References: <20231130105459.3208986-1-lee@kernel.org> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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 Cc: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org Signed-off-by: Lee Jones --- 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; }