diff mbox

[for-1.2] hw/arm_gic.c: Define .class_size in arm_gic_info TypeInfo

Message ID 1346226757-24968-1-git-send-email-peter.maydell@linaro.org
State Accepted
Commit 998a74bcda7f3297813732ddc2f28ffe5a12e37a
Headers show

Commit Message

Peter Maydell Aug. 29, 2012, 7:52 a.m. UTC
Add the missing .class_size definition to the arm_gic_info TypeInfo.
This fixes the memory corruption and possible segfault that otherwise
results when the class struct is allocated at too small a size and
the class init function writes off the end of it.

Reported-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
Oops. I suspect this only crashes on 32 bit hosts because the class
is only one field larger than its subclass, so on 64 bit systems
we are probably only overwriting padding rather than anything
important. For 1.2 since it fixes a segfault.

 hw/arm_gic.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

Comments

Andreas Färber Aug. 30, 2012, 1:06 p.m. UTC | #1
Am 29.08.2012 20:57, schrieb Stefan Weil:
> PS. Are there perhaps more bugs of this sort? A quick test looking
> for .class_init without .class_size shows a lot of files.

That alone is not wrong.

A problem only arises when a new struct ...Class is casted to but the
object not sized appropriately through .class_size.

Andreas
diff mbox

Patch

diff --git a/hw/arm_gic.c b/hw/arm_gic.c
index 186ac66..55871fa 100644
--- a/hw/arm_gic.c
+++ b/hw/arm_gic.c
@@ -703,6 +703,7 @@  static TypeInfo arm_gic_info = {
     .parent = TYPE_ARM_GIC_COMMON,
     .instance_size = sizeof(gic_state),
     .class_init = arm_gic_class_init,
+    .class_size = sizeof(ARMGICClass),
 };
 
 static void arm_gic_register_types(void)