On 06/01/2022 12:22, Laurent Vivier wrote:
"qemu-system-m68k -M q800 -bios /dev/null" crahses with a segfault
in q800_init().
This happens because the code doesn't check that rom_ptr() returned
a non-NULL pointer .
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/756
Reported-by: Peter Maydell <peter.mayd...@linaro.org>
Signed-off-by: Laurent Vivier <laur...@vivier.eu>
---
hw/m68k/q800.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
index e4c7c9b88ad0..6261716c8f7e 100644
--- a/hw/m68k/q800.c
+++ b/hw/m68k/q800.c
@@ -672,10 +672,16 @@ static void q800_init(MachineState *machine)
/* Remove qtest_enabled() check once firmware files are in the tree */
if (!qtest_enabled()) {
- if (bios_size < 0 || bios_size > MACROM_SIZE) {
+ if (bios_size == -1) {
error_report("could not load MacROM '%s'", bios_name);
exit(1);
}
+ if (bios_size != MACROM_SIZE) {
+ error_report("Invalid size for MacROM '%s': %d bytes,"
+ " expected %d bytes", bios_name, bios_size,
+ MACROM_SIZE);
+ exit(1);
+ }
ptr = rom_ptr(MACROM_ADDR, MACROM_SIZE);
stl_phys(cs->as, 0, ldl_p(ptr)); /* reset initial SP */
The patch does fix the issue, but it seems a little odd that you can't use -bios
path/to/m68k-binary to boot with an arbitrary sized binary which could be useful for
reproducers such as https://gitlab.com/qemu-project/qemu/-/issues/360.
How easy would it be to add the extra rom_ptr() NULL check instead?
ATB,
Mark.
