Hi; This patch (rediffed againg kvm-60) from Tavis Ormandy <[EMAIL PROTECTED]> fixes CVE-2007-1320 [1]
Again, I'm not sure why qemu upstream not merged these but Xen already did [2]. [1] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-1320 [2] http://xenbits.xensource.com/xen-3.1-testing.hg?rev/9e86260b95a4 diff -ur kvm-60.orig/qemu/hw/cirrus_vga.c kvm-60/qemu/hw/cirrus_vga.c --- kvm-60.orig/qemu/hw/cirrus_vga.c 2008-01-20 14:35:04.000000000 +0200 +++ kvm-60/qemu/hw/cirrus_vga.c 2008-01-29 01:45:48.000000000 +0200 @@ -223,6 +223,20 @@ #define CIRRUS_HOOK_NOT_HANDLED 0 #define CIRRUS_HOOK_HANDLED 1 +#define BLTUNSAFE(s) \ + ( \ + ( /* check dst is within bounds */ \ + (s)->cirrus_blt_height * (s)->cirrus_blt_dstpitch \ + + ((s)->cirrus_blt_dstaddr & (s)->cirrus_addr_mask) > \ + (s)->vram_size \ + ) || \ + ( /* check src is within bounds */ \ + (s)->cirrus_blt_height * (s)->cirrus_blt_srcpitch \ + + ((s)->cirrus_blt_srcaddr & (s)->cirrus_addr_mask) > \ + (s)->vram_size \ + ) \ + ) + struct CirrusVGAState; typedef void (*cirrus_bitblt_rop_t) (struct CirrusVGAState *s, uint8_t * dst, const uint8_t * src, @@ -649,7 +663,7 @@ for (y = 0; y < lines; y++) { off_cur = off_begin; - off_cur_end = off_cur + bytesperline; + off_cur_end = (off_cur + bytesperline) & s->cirrus_addr_mask; off_cur &= TARGET_PAGE_MASK; while (off_cur < off_cur_end) { cpu_physical_memory_set_dirty(s->vram_offset + off_cur); @@ -664,7 +678,11 @@ { uint8_t *dst; - dst = s->vram_ptr + s->cirrus_blt_dstaddr; + dst = s->vram_ptr + (s->cirrus_blt_dstaddr & s->cirrus_addr_mask); + + if (BLTUNSAFE(s)) + return 0; + (*s->cirrus_rop) (s, dst, src, s->cirrus_blt_dstpitch, 0, s->cirrus_blt_width, s->cirrus_blt_height); @@ -680,8 +698,10 @@ { cirrus_fill_t rop_func; + if (BLTUNSAFE(s)) + return 0; rop_func = cirrus_fill[rop_to_index[blt_rop]][s->cirrus_blt_pixelwidth - 1]; - rop_func(s, s->vram_ptr + s->cirrus_blt_dstaddr, + rop_func(s, s->vram_ptr + (s->cirrus_blt_dstaddr & s->cirrus_addr_mask), s->cirrus_blt_dstpitch, s->cirrus_blt_width, s->cirrus_blt_height); cirrus_invalidate_region(s, s->cirrus_blt_dstaddr, @@ -700,8 +720,8 @@ static int cirrus_bitblt_videotovideo_patterncopy(CirrusVGAState * s) { return cirrus_bitblt_common_patterncopy(s, - s->vram_ptr + - (s->cirrus_blt_srcaddr & ~7)); + s->vram_ptr + ((s->cirrus_blt_srcaddr & ~7) & + s->cirrus_addr_mask)); } static void cirrus_do_copy(CirrusVGAState *s, int dst, int src, int w, int h) @@ -751,8 +771,10 @@ if (notify) vga_hw_update(); - (*s->cirrus_rop) (s, s->vram_ptr + s->cirrus_blt_dstaddr, - s->vram_ptr + s->cirrus_blt_srcaddr, + (*s->cirrus_rop) (s, s->vram_ptr + + (s->cirrus_blt_dstaddr & s->cirrus_addr_mask), + s->vram_ptr + + (s->cirrus_blt_srcaddr & s->cirrus_addr_mask), s->cirrus_blt_dstpitch, s->cirrus_blt_srcpitch, s->cirrus_blt_width, s->cirrus_blt_height); @@ -778,8 +800,14 @@ s->cirrus_blt_srcaddr - s->start_addr, s->cirrus_blt_width, s->cirrus_blt_height); } else { - (*s->cirrus_rop) (s, s->vram_ptr + s->cirrus_blt_dstaddr, - s->vram_ptr + s->cirrus_blt_srcaddr, + + if (BLTUNSAFE(s)) + return 0; + + (*s->cirrus_rop) (s, s->vram_ptr + + (s->cirrus_blt_dstaddr & s->cirrus_addr_mask), + s->vram_ptr + + (s->cirrus_blt_srcaddr & s->cirrus_addr_mask), s->cirrus_blt_dstpitch, s->cirrus_blt_srcpitch, s->cirrus_blt_width, s->cirrus_blt_height); @@ -811,8 +839,9 @@ } else { /* at least one scan line */ do { - (*s->cirrus_rop)(s, s->vram_ptr + s->cirrus_blt_dstaddr, - s->cirrus_bltbuf, 0, 0, s->cirrus_blt_width, 1); + (*s->cirrus_rop)(s, s->vram_ptr + + (s->cirrus_blt_dstaddr & s->cirrus_addr_mask), + s->cirrus_bltbuf, 0, 0, s->cirrus_blt_width, 1); cirrus_invalidate_region(s, s->cirrus_blt_dstaddr, 0, s->cirrus_blt_width, 1); s->cirrus_blt_dstaddr += s->cirrus_blt_dstpitch; @@ -1933,7 +1962,7 @@ unsigned val = mem_value; uint8_t *dst; - dst = s->vram_ptr + offset; + dst = s->vram_ptr + (offset &= s->cirrus_addr_mask); for (x = 0; x < 8; x++) { if (val & 0x80) { *dst = s->cirrus_shadow_gr1; @@ -1956,7 +1985,7 @@ unsigned val = mem_value; uint8_t *dst; - dst = s->vram_ptr + offset; + dst = s->vram_ptr + (offset &= s->cirrus_addr_mask); for (x = 0; x < 8; x++) { if (val & 0x80) { *dst = s->cirrus_shadow_gr1; Yalnızca kvm-60/qemu/hw'da: cirrus_vga.c.orig diff -ur kvm-60.orig/qemu/hw/cirrus_vga_rop.h kvm-60/qemu/hw/cirrus_vga_rop.h --- kvm-60.orig/qemu/hw/cirrus_vga_rop.h 2008-01-20 14:35:04.000000000 +0200 +++ kvm-60/qemu/hw/cirrus_vga_rop.h 2008-01-29 01:45:48.000000000 +0200 @@ -31,6 +31,12 @@ int x,y; dstpitch -= bltwidth; srcpitch -= bltwidth; + + if (dstpitch < 0 || srcpitch < 0) { + /* is 0 valid? srcpitch == 0 could be useful */ + return; + } + for (y = 0; y < bltheight; y++) { for (x = 0; x < bltwidth; x++) { ROP_OP(*dst, *src); Cheers -- S.Çağlar Onur <[EMAIL PROTECTED]> http://cekirdek.pardus.org.tr/~caglar/ Linux is like living in a teepee. No Windows, no Gates and an Apache in house! ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel