When calculating a pointer to the currently selected fw_cfg item, the
following is used:
FWCfgEntry *e = &s->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK];
When s->cur_entry is FW_CFG_INVALID, we are calculating the address of
a non-existent element in s->entries[arch][...], which is undefined.
This patch ensures the resulting entry pointer is set to NULL whenever
s->cur_entry is FW_CFG_INVALID.
Reported-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Message-id:
1446733972-1602-5-git-send-email-somlo@cmu.edu
Cc: Marc MarĂ <markmb@redhat.com>
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
static uint8_t fw_cfg_read(FWCfgState *s)
{
int arch = !!(s->cur_entry & FW_CFG_ARCH_LOCAL);
- FWCfgEntry *e = &s->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK];
+ FWCfgEntry *e = (s->cur_entry == FW_CFG_INVALID) ? NULL :
+ &s->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK];
uint8_t ret;
if (s->cur_entry == FW_CFG_INVALID || !e->data || s->cur_offset >= e->len)
}
arch = !!(s->cur_entry & FW_CFG_ARCH_LOCAL);
- e = &s->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK];
+ e = (s->cur_entry == FW_CFG_INVALID) ? NULL :
+ &s->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK];
if (dma.control & FW_CFG_DMA_CTL_READ) {
read = 1;