From patchwork Mon Jan 9 18:43:57 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Peter Maydell X-Patchwork-Id: 90553 Delivered-To: patches@linaro.org Received: by 10.140.20.99 with SMTP id 90csp220742qgi; Mon, 9 Jan 2017 10:44:03 -0800 (PST) X-Received: by 10.28.158.196 with SMTP id h187mr5699960wme.59.1483987443334; Mon, 09 Jan 2017 10:44:03 -0800 (PST) Return-Path: Received: from orth.archaic.org.uk (orth.archaic.org.uk. [2001:8b0:1d0::2]) by mx.google.com with ESMTPS id w70si8902686wrc.19.2017.01.09.10.44.03 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 09 Jan 2017 10:44:03 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of pm215@archaic.org.uk designates 2001:8b0:1d0::2 as permitted sender) client-ip=2001:8b0:1d0::2; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of pm215@archaic.org.uk designates 2001:8b0:1d0::2 as permitted sender) smtp.mailfrom=pm215@archaic.org.uk; dmarc=fail (p=NONE dis=NONE) header.from=linaro.org Received: from pm215 by orth.archaic.org.uk with local (Exim 4.84_2) (envelope-from ) id 1cQevG-0001yq-KL; Mon, 09 Jan 2017 18:43:58 +0000 From: Peter Maydell To: qemu-devel@nongnu.org Cc: patches@linaro.org, Jason Wang , Laurent Vivier , =?UTF-8?q?Herv=C3=A9=20Poussineau?= , Aurelien Jarno Subject: [PATCH] hw/net/dp8393x: Avoid unintentional sign extensions on addresses Date: Mon, 9 Jan 2017 18:43:57 +0000 Message-Id: <1483987437-12084-1-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 2.7.4 The dp8393x has several 32-bit values which are formed by concatenating two 16 bit device register values. Attempting to do these inline with ((s->reg[HI] << 16) | s->reg[LO]) can result in an unintended sign extension because "x << 16" is of type 'int' even though s->reg is unsigned, and so if the expression is used in a context where it is cast to uint64_t the value is incorrectly sign-extended. Fix this by using accessor functions with a uint32_t return type; this also makes the code a bit easier to read. This should fix Coverity issues 1307765, 1307766, 1307767, 1307768. (To avoid having a ctda read function only used in a DPRINTF, we move the DPRINTF down slightly so it can use the ttda function.) Signed-off-by: Peter Maydell --- Disclaimer: only compile tested as this device only exists on the MIPS magnum/pica61 boards and I don't have an image for them. hw/net/dp8393x.c | 95 ++++++++++++++++++++++++++++++++++++++++---------------- 1 file changed, 68 insertions(+), 27 deletions(-) -- 2.7.4 Reviewed-by: Laurent Vivier Tested-by: Laurent Vivier Reviewed-by: Hervé Poussineau diff --git a/hw/net/dp8393x.c b/hw/net/dp8393x.c index 17f0338..efa33ad 100644 --- a/hw/net/dp8393x.c +++ b/hw/net/dp8393x.c @@ -174,6 +174,52 @@ typedef struct dp8393xState { AddressSpace as; } dp8393xState; +/* Accessor functions for values which are formed by + * concatenating two 16 bit device registers. By putting these + * in their own functions with a uint32_t return type we avoid the + * pitfall of implicit sign extension where ((x << 16) | y) is a + * signed 32 bit integer that might get sign-extended to a 64 bit integer. + */ +static uint32_t dp8393x_cdp(dp8393xState *s) +{ + return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_CDP]; +} + +static uint32_t dp8393x_crba(dp8393xState *s) +{ + return (s->regs[SONIC_CRBA1] << 16) | s->regs[SONIC_CRBA0]; +} + +static uint32_t dp8393x_crda(dp8393xState *s) +{ + return (s->regs[SONIC_URDA] << 16) | s->regs[SONIC_CRDA]; +} + +static uint32_t dp8393x_rbwc(dp8393xState *s) +{ + return (s->regs[SONIC_RBWC1] << 16) | s->regs[SONIC_RBWC0]; +} + +static uint32_t dp8393x_rrp(dp8393xState *s) +{ + return (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_RRP]; +} + +static uint32_t dp8393x_tsa(dp8393xState *s) +{ + return (s->regs[SONIC_TSA1] << 16) | s->regs[SONIC_TSA0]; +} + +static uint32_t dp8393x_ttda(dp8393xState *s) +{ + return (s->regs[SONIC_UTDA] << 16) | s->regs[SONIC_TTDA]; +} + +static uint32_t dp8393x_wt(dp8393xState *s) +{ + return s->regs[SONIC_WT1] << 16 | s->regs[SONIC_WT0]; +} + static void dp8393x_update_irq(dp8393xState *s) { int level = (s->regs[SONIC_IMR] & s->regs[SONIC_ISR]) ? 1 : 0; @@ -203,8 +249,7 @@ static void dp8393x_do_load_cam(dp8393xState *s) while (s->regs[SONIC_CDC] & 0x1f) { /* Fill current entry */ - address_space_rw(&s->as, - (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_CDP], + address_space_rw(&s->as, dp8393x_cdp(s), MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 0); s->cam[index][0] = data[1 * width] & 0xff; s->cam[index][1] = data[1 * width] >> 8; @@ -222,8 +267,7 @@ static void dp8393x_do_load_cam(dp8393xState *s) } /* Read CAM enable */ - address_space_rw(&s->as, - (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_CDP], + address_space_rw(&s->as, dp8393x_cdp(s), MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 0); s->regs[SONIC_CE] = data[0 * width]; DPRINTF("load cam done. cam enable mask 0x%04x\n", s->regs[SONIC_CE]); @@ -242,8 +286,7 @@ static void dp8393x_do_read_rra(dp8393xState *s) /* Read memory */ width = (s->regs[SONIC_DCR] & SONIC_DCR_DW) ? 2 : 1; size = sizeof(uint16_t) * 4 * width; - address_space_rw(&s->as, - (s->regs[SONIC_URRA] << 16) | s->regs[SONIC_RRP], + address_space_rw(&s->as, dp8393x_rrp(s), MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 0); /* Update SONIC registers */ @@ -292,7 +335,7 @@ static void dp8393x_set_next_tick(dp8393xState *s) return; } - ticks = s->regs[SONIC_WT1] << 16 | s->regs[SONIC_WT0]; + ticks = dp8393x_wt(s); s->wt_last_update = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); delay = NANOSECONDS_PER_SECOND * ticks / 5000000; timer_mod(s->watchdog, s->wt_last_update + delay); @@ -309,7 +352,7 @@ static void dp8393x_update_wt_regs(dp8393xState *s) } elapsed = s->wt_last_update - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); - val = s->regs[SONIC_WT1] << 16 | s->regs[SONIC_WT0]; + val = dp8393x_wt(s); val -= elapsed / 5000000; s->regs[SONIC_WT1] = (val >> 16) & 0xffff; s->regs[SONIC_WT0] = (val >> 0) & 0xffff; @@ -356,12 +399,11 @@ static void dp8393x_do_transmit_packets(dp8393xState *s) while (1) { /* Read memory */ - DPRINTF("Transmit packet at %08x\n", - (s->regs[SONIC_UTDA] << 16) | s->regs[SONIC_CTDA]); size = sizeof(uint16_t) * 6 * width; s->regs[SONIC_TTDA] = s->regs[SONIC_CTDA]; + DPRINTF("Transmit packet at %08x\n", dp8393x_ttda(s)); address_space_rw(&s->as, - ((s->regs[SONIC_UTDA] << 16) | s->regs[SONIC_TTDA]) + sizeof(uint16_t) * width, + dp8393x_ttda(s) + sizeof(uint16_t) * width, MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 0); tx_len = 0; @@ -386,8 +428,7 @@ static void dp8393x_do_transmit_packets(dp8393xState *s) if (tx_len + len > sizeof(s->tx_buffer)) { len = sizeof(s->tx_buffer) - tx_len; } - address_space_rw(&s->as, - (s->regs[SONIC_TSA1] << 16) | s->regs[SONIC_TSA0], + address_space_rw(&s->as, dp8393x_tsa(s), MEMTXATTRS_UNSPECIFIED, &s->tx_buffer[tx_len], len, 0); tx_len += len; @@ -396,7 +437,7 @@ static void dp8393x_do_transmit_packets(dp8393xState *s) /* Read next fragment details */ size = sizeof(uint16_t) * 3 * width; address_space_rw(&s->as, - ((s->regs[SONIC_UTDA] << 16) | s->regs[SONIC_TTDA]) + sizeof(uint16_t) * (4 + 3 * i) * width, + dp8393x_ttda(s) + sizeof(uint16_t) * (4 + 3 * i) * width, MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 0); s->regs[SONIC_TSA0] = data[0 * width]; s->regs[SONIC_TSA1] = data[1 * width]; @@ -430,14 +471,16 @@ static void dp8393x_do_transmit_packets(dp8393xState *s) data[0 * width] = s->regs[SONIC_TCR] & 0x0fff; /* status */ size = sizeof(uint16_t) * width; address_space_rw(&s->as, - (s->regs[SONIC_UTDA] << 16) | s->regs[SONIC_TTDA], + dp8393x_ttda(s), MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 1); if (!(s->regs[SONIC_CR] & SONIC_CR_HTX)) { /* Read footer of packet */ size = sizeof(uint16_t) * width; address_space_rw(&s->as, - ((s->regs[SONIC_UTDA] << 16) | s->regs[SONIC_TTDA]) + sizeof(uint16_t) * (4 + 3 * s->regs[SONIC_TFC]) * width, + dp8393x_ttda(s) + + sizeof(uint16_t) * + (4 + 3 * s->regs[SONIC_TFC]) * width, MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 0); s->regs[SONIC_CTDA] = data[0 * width] & ~0x1; if (data[0 * width] & 0x1) { @@ -700,7 +743,7 @@ static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf, if (s->regs[SONIC_LLFA] & 0x1) { /* Are we still in resource exhaustion? */ size = sizeof(uint16_t) * 1 * width; - address = ((s->regs[SONIC_URDA] << 16) | s->regs[SONIC_CRDA]) + sizeof(uint16_t) * 5 * width; + address = dp8393x_crda(s) + sizeof(uint16_t) * 5 * width; address_space_rw(&s->as, address, MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 0); if (data[0 * width] & 0x1) { @@ -719,8 +762,8 @@ static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf, checksum = cpu_to_le32(crc32(0, buf, rx_len)); /* Put packet into RBA */ - DPRINTF("Receive packet at %08x\n", (s->regs[SONIC_CRBA1] << 16) | s->regs[SONIC_CRBA0]); - address = (s->regs[SONIC_CRBA1] << 16) | s->regs[SONIC_CRBA0]; + DPRINTF("Receive packet at %08x\n", dp8393x_crba(s)); + address = dp8393x_crba(s); address_space_rw(&s->as, address, MEMTXATTRS_UNSPECIFIED, (uint8_t *)buf, rx_len, 1); address += rx_len; @@ -729,13 +772,13 @@ static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf, rx_len += 4; s->regs[SONIC_CRBA1] = address >> 16; s->regs[SONIC_CRBA0] = address & 0xffff; - available = (s->regs[SONIC_RBWC1] << 16) | s->regs[SONIC_RBWC0]; + available = dp8393x_rbwc(s); available -= rx_len / 2; s->regs[SONIC_RBWC1] = available >> 16; s->regs[SONIC_RBWC0] = available & 0xffff; /* Update status */ - if (((s->regs[SONIC_RBWC1] << 16) | s->regs[SONIC_RBWC0]) < s->regs[SONIC_EOBC]) { + if (dp8393x_rbwc(s) < s->regs[SONIC_EOBC]) { s->regs[SONIC_RCR] |= SONIC_RCR_LPKT; } s->regs[SONIC_RCR] |= packet_type; @@ -746,20 +789,19 @@ static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf, } /* Write status to memory */ - DPRINTF("Write status at %08x\n", (s->regs[SONIC_URDA] << 16) | s->regs[SONIC_CRDA]); + DPRINTF("Write status at %08x\n", dp8393x_crda(s)); data[0 * width] = s->regs[SONIC_RCR]; /* status */ data[1 * width] = rx_len; /* byte count */ data[2 * width] = s->regs[SONIC_TRBA0]; /* pkt_ptr0 */ data[3 * width] = s->regs[SONIC_TRBA1]; /* pkt_ptr1 */ data[4 * width] = s->regs[SONIC_RSC]; /* seq_no */ size = sizeof(uint16_t) * 5 * width; - address_space_rw(&s->as, (s->regs[SONIC_URDA] << 16) | s->regs[SONIC_CRDA], + address_space_rw(&s->as, dp8393x_crda(s), MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 1); /* Move to next descriptor */ size = sizeof(uint16_t) * width; - address_space_rw(&s->as, - ((s->regs[SONIC_URDA] << 16) | s->regs[SONIC_CRDA]) + sizeof(uint16_t) * 5 * width, + address_space_rw(&s->as, dp8393x_crda(s) + sizeof(uint16_t) * 5 * width, MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, size, 0); s->regs[SONIC_LLFA] = data[0 * width]; if (s->regs[SONIC_LLFA] & 0x1) { @@ -767,8 +809,7 @@ static ssize_t dp8393x_receive(NetClientState *nc, const uint8_t * buf, s->regs[SONIC_ISR] |= SONIC_ISR_RDE; } else { data[0 * width] = 0; /* in_use */ - address_space_rw(&s->as, - ((s->regs[SONIC_URDA] << 16) | s->regs[SONIC_CRDA]) + sizeof(uint16_t) * 6 * width, + address_space_rw(&s->as, dp8393x_crda(s) + sizeof(uint16_t) * 6 * width, MEMTXATTRS_UNSPECIFIED, (uint8_t *)data, sizeof(uint16_t), 1); s->regs[SONIC_CRDA] = s->regs[SONIC_LLFA]; s->regs[SONIC_ISR] |= SONIC_ISR_PKTRX;