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f9f705bf3c
Adding the offset between the realloc result and the old allocation to update pointers into the new allocation is undefined behaviour: the old pointers are no longer valid after realloc() according to the C standard. While this works on almost all architectures and compilers, it causes problems on architectures that track pointer bounds (e.g. CHERI or Arm's Morello): the DevPrivateKey pointers will still have the bounds of the previous allocation and therefore any dereference will result in a run-time trap. I found this due to a crash (dereferencing an invalid capability) while trying to run `XVnc` on a CHERI-RISC-V system. With this commit I can successfully connect to the XVnc instance running inside a QEMU with a VNC viewer on my host. This also changes the check whether the allocation was moved to use uintptr_t instead of a pointer since according to the C standard: "The value of a pointer becomes indeterminate when the object it points to (or just past) reaches the end of its lifetime." Casting to an integer type avoids this undefined behaviour. Signed-off-by: Alex Richardson <Alexander.Richardson@cl.cam.ac.uk> |
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| .. | ||
| .gitignore | ||
| atom.c | ||
| buildatoms | ||
| BuiltInAtoms | ||
| colormap.c | ||
| cursor.c | ||
| devices.c | ||
| dispatch.c | ||
| dispatch.h | ||
| dixfonts.c | ||
| dixutils.c | ||
| enterleave.c | ||
| enterleave.h | ||
| eventconvert.c | ||
| events.c | ||
| extension.c | ||
| gc.c | ||
| gestures.c | ||
| getevents.c | ||
| globals.c | ||
| glyphcurs.c | ||
| grabs.c | ||
| initatoms.c | ||
| inpututils.c | ||
| main.c | ||
| Makefile.am | ||
| meson.build | ||
| pixmap.c | ||
| privates.c | ||
| property.c | ||
| protocol.txt | ||
| ptrveloc.c | ||
| region.c | ||
| registry.c | ||
| resource.c | ||
| selection.c | ||
| stubmain.c | ||
| swaprep.c | ||
| swapreq.c | ||
| tables.c | ||
| touch.c | ||
| window.c | ||