[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] [PATCH v2] Minor change to avoid potental overflow accessing pci option roms

When scan pci option roms space, there is possibility to access beyond

This patch makes the code robust though there are other checks such as
0x55AA signature.

Bug was found by code inspection.

v2: Add description per Konrad's suggestion, thanks.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxxx>
 tools/firmware/rombios/rombios.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/firmware/rombios/rombios.c b/tools/firmware/rombios/rombios.c
index 057aced..f5ac33e 100644
--- a/tools/firmware/rombios/rombios.c
+++ b/tools/firmware/rombios/rombios.c
@@ -10648,7 +10648,7 @@ rom_scan_increment:
   add  cx, ax
   pop  ax       ;; Restore AX
   cmp  cx, ax
-  jbe  rom_scan_loop
+  jb  rom_scan_loop
   xor  ax, ax   ;; Restore DS back to 0000:
   mov  ds, ax
@@ -11022,7 +11022,7 @@ post_default_ints:
   call post_init_pic
   mov  cx, #0xc000  ;; init vga bios
-  mov  ax, #0xc780
+  mov  ax, #0xc800
   call rom_scan
   call _print_bios_banner

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.