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[PULL,V2,13/14] hw/net/allwinner-sun8i-emac.c: Fix REG_ADDR_HIGH/LOW reads

Message ID 1585660899-11228-14-git-send-email-jasowang@redhat.com
State Accepted
Commit b88fb1247b8f82ff49a82e69965adca6d329a3b3
Headers show
Series None | expand

Commit Message

Jason Wang March 31, 2020, 1:21 p.m. UTC 
From: Peter Maydell <peter.maydell@linaro.org>


Coverity points out (CID 1421926) that the read code for
REG_ADDR_HIGH reads off the end of the buffer, because it does a
32-bit read from byte 4 of a 6-byte buffer.

The code also has an endianness issue for both REG_ADDR_HIGH and
REG_ADDR_LOW, because it will do the wrong thing on a big-endian
host.

Rewrite the read code to use ldl_le_p() and lduw_le_p() to fix this;
the write code is not incorrect, but for consistency we make it use
stl_le_p() and stw_le_p().

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Tested-by: Niek Linnenbank <nieklinnenbank@gmail.com>

Reviewed-by: Niek Linnenbank <nieklinnenbank@gmail.com>

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Signed-off-by: Jason Wang <jasowang@redhat.com>

---
 hw/net/allwinner-sun8i-emac.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

-- 
2.5.0
diff mbox series

Patch

diff --git a/hw/net/allwinner-sun8i-emac.c b/hw/net/allwinner-sun8i-emac.c
index 033eaa8..28637ff 100644
--- a/hw/net/allwinner-sun8i-emac.c
+++ b/hw/net/allwinner-sun8i-emac.c
@@ -611,10 +611,10 @@  static uint64_t allwinner_sun8i_emac_read(void *opaque, hwaddr offset,
         value = s->mii_data;
         break;
     case REG_ADDR_HIGH:         /* MAC Address High */
-        value = *(((uint32_t *) (s->conf.macaddr.a)) + 1);
+        value = lduw_le_p(s->conf.macaddr.a + 4);
         break;
     case REG_ADDR_LOW:          /* MAC Address Low */
-        value = *(uint32_t *) (s->conf.macaddr.a);
+        value = ldl_le_p(s->conf.macaddr.a);
         break;
     case REG_TX_DMA_STA:        /* Transmit DMA Status */
         break;
@@ -728,14 +728,10 @@  static void allwinner_sun8i_emac_write(void *opaque, hwaddr offset,
         s->mii_data = value;
         break;
     case REG_ADDR_HIGH:         /* MAC Address High */
-        s->conf.macaddr.a[4] = (value & 0xff);
-        s->conf.macaddr.a[5] = (value & 0xff00) >> 8;
+        stw_le_p(s->conf.macaddr.a + 4, value);
         break;
     case REG_ADDR_LOW:          /* MAC Address Low */
-        s->conf.macaddr.a[0] = (value & 0xff);
-        s->conf.macaddr.a[1] = (value & 0xff00) >> 8;
-        s->conf.macaddr.a[2] = (value & 0xff0000) >> 16;
-        s->conf.macaddr.a[3] = (value & 0xff000000) >> 24;
+        stl_le_p(s->conf.macaddr.a, value);
         break;
     case REG_TX_DMA_STA:        /* Transmit DMA Status */
     case REG_TX_CUR_DESC:       /* Transmit Current Descriptor */