diff options
| -rw-r--r-- | hw/display/vga.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/hw/display/vga.c b/hw/display/vga.c index 657e9f1..b9191ca 100644 --- a/hw/display/vga.c +++ b/hw/display/vga.c @@ -179,6 +179,7 @@ static void vga_update_memory_access(VGACommonState *s) size = 0x8000; break; } + assert(offset + size <= s->vram_size); memory_region_init_alias(&s->chain4_alias, memory_region_owner(&s->vram), "vga.chain4", &s->vram, offset, size); memory_region_add_subregion_overlap(s->legacy_address_space, base, @@ -716,11 +717,7 @@ void vbe_ioport_write_data(void *opaque, uint32_t addr, uint32_t val) vbe_fixup_regs(s); break; case VBE_DISPI_INDEX_BANK: - if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4) { - val &= (s->vbe_bank_mask >> 2); - } else { - val &= s->vbe_bank_mask; - } + val &= s->vbe_bank_mask; s->vbe_regs[s->vbe_index] = val; s->bank_offset = (val << 16); vga_update_memory_access(s); @@ -819,13 +816,21 @@ uint32_t vga_mem_readb(VGACommonState *s, hwaddr addr) if (s->sr[VGA_SEQ_MEMORY_MODE] & VGA_SR04_CHN_4M) { /* chain 4 mode : simplest access */ + assert(addr < s->vram_size); ret = s->vram_ptr[addr]; } else if (s->gr[VGA_GFX_MODE] & 0x10) { /* odd/even mode (aka text mode mapping) */ plane = (s->gr[VGA_GFX_PLANE_READ] & 2) | (addr & 1); - ret = s->vram_ptr[((addr & ~1) << 1) | plane]; + addr = ((addr & ~1) << 1) | plane; + if (addr >= s->vram_size) { + return 0xff; + } + ret = s->vram_ptr[addr]; } else { /* standard VGA latched access */ + if (addr * sizeof(uint32_t) >= s->vram_size) { + return 0xff; + } s->latch = ((uint32_t *)s->vram_ptr)[addr]; if (!(s->gr[VGA_GFX_MODE] & 0x08)) { @@ -882,6 +887,7 @@ void vga_mem_writeb(VGACommonState *s, hwaddr addr, uint32_t val) plane = addr & 3; mask = (1 << plane); if (s->sr[VGA_SEQ_PLANE_WRITE] & mask) { + assert(addr < s->vram_size); s->vram_ptr[addr] = val; #ifdef DEBUG_VGA_MEM printf("vga: chain4: [0x" TARGET_FMT_plx "]\n", addr); @@ -895,6 +901,9 @@ void vga_mem_writeb(VGACommonState *s, hwaddr addr, uint32_t val) mask = (1 << plane); if (s->sr[VGA_SEQ_PLANE_WRITE] & mask) { addr = ((addr & ~1) << 1) | plane; + if (addr >= s->vram_size) { + return; + } s->vram_ptr[addr] = val; #ifdef DEBUG_VGA_MEM printf("vga: odd/even: [0x" TARGET_FMT_plx "]\n", addr); @@ -968,6 +977,9 @@ void vga_mem_writeb(VGACommonState *s, hwaddr addr, uint32_t val) mask = s->sr[VGA_SEQ_PLANE_WRITE]; s->plane_updated |= mask; /* only used to detect font change */ write_mask = mask16[mask]; + if (addr * sizeof(uint32_t) >= s->vram_size) { + return; + } ((uint32_t *)s->vram_ptr)[addr] = (((uint32_t *)s->vram_ptr)[addr] & ~write_mask) | (val & write_mask); |