rtl8139: do not assume TxStatus[] and TxAddr[] are adjacent

Commit afe0a59535 ("rtl8139: support byte
read to TxStatus registers") reused rtl8139_TxStatus_read() for reading
TxAddr registers.  It relies on the fact that TxStatus[] and TxAddr[]
are adjacent.

This causes a gcc warning because the compiler can detect that array
access is out-of-bounds:

  hw/rtl8139.c:2501:27: error: array subscript is above array bounds [-Werror=array-bounds]

This patch refactors the function so that we don't rely on out-of-bounds
accesses.

Cc: Jason Wang <jasonwang@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Stefan Hajnoczi 2012-04-11 12:01:44 +01:00 committed by Anthony Liguori
parent c1958aea51
commit 3e48dd4a2d

View File

@ -2482,15 +2482,17 @@ static void rtl8139_TxStatus_write(RTL8139State *s, uint32_t txRegOffset, uint32
rtl8139_transmit(s);
}
static uint32_t rtl8139_TxStatus_read(RTL8139State *s, uint8_t addr, int size)
static uint32_t rtl8139_TxStatus_TxAddr_read(RTL8139State *s, uint32_t regs[],
uint32_t base, uint8_t addr,
int size)
{
uint32_t reg = (addr - TxStatus0) / 4;
uint32_t reg = (addr - base) / 4;
uint32_t offset = addr & 0x3;
uint32_t ret = 0;
if (addr & (size - 1)) {
DPRINTF("not implemented read for TxStatus addr=0x%x size=0x%x\n", addr,
size);
DPRINTF("not implemented read for TxStatus/TxAddr "
"addr=0x%x size=0x%x\n", addr, size);
return ret;
}
@ -2498,12 +2500,12 @@ static uint32_t rtl8139_TxStatus_read(RTL8139State *s, uint8_t addr, int size)
case 1: /* fall through */
case 2: /* fall through */
case 4:
ret = (s->TxStatus[reg] >> offset * 8) & ((1 << (size * 8)) - 1);
DPRINTF("TxStatus[%d] read addr=0x%x size=0x%x val=0x%08x\n", reg, addr,
size, ret);
ret = (regs[reg] >> offset * 8) & ((1 << (size * 8)) - 1);
DPRINTF("TxStatus/TxAddr[%d] read addr=0x%x size=0x%x val=0x%08x\n",
reg, addr, size, ret);
break;
default:
DPRINTF("unsupported size 0x%x of TxStatus reading\n", size);
DPRINTF("unsupported size 0x%x of TxStatus/TxAddr reading\n", size);
break;
}
@ -2977,7 +2979,8 @@ static uint32_t rtl8139_io_readb(void *opaque, uint8_t addr)
ret = s->mult[addr - MAR0];
break;
case TxStatus0 ... TxStatus0+4*4-1:
ret = rtl8139_TxStatus_read(s, addr, 1);
ret = rtl8139_TxStatus_TxAddr_read(s, s->TxStatus, TxStatus0,
addr, 1);
break;
case ChipCmd:
ret = rtl8139_ChipCmd_read(s);
@ -3043,7 +3046,7 @@ static uint32_t rtl8139_io_readw(void *opaque, uint8_t addr)
switch (addr)
{
case TxAddr0 ... TxAddr0+4*4-1:
ret = rtl8139_TxStatus_read(s, addr, 2);
ret = rtl8139_TxStatus_TxAddr_read(s, s->TxAddr, TxAddr0, addr, 2);
break;
case IntrMask:
ret = rtl8139_IntrMask_read(s);
@ -3135,7 +3138,8 @@ static uint32_t rtl8139_io_readl(void *opaque, uint8_t addr)
break;
case TxStatus0 ... TxStatus0+4*4-1:
ret = rtl8139_TxStatus_read(s, addr, 4);
ret = rtl8139_TxStatus_TxAddr_read(s, s->TxStatus, TxStatus0,
addr, 4);
break;
case TxAddr0 ... TxAddr0+4*4-1: