Unicorn CPU emulator framework (ARM, AArch64, M68K, Mips, Sparc, X86)
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Peter Maydell 1a3abaa81a target/i386: Check privilege level for protected mode 'int N' task gate
When the 'int N' instruction is executed in protected mode, the
pseudocode in the architecture manual specifies that we need to check:

* vector number within IDT limits
* selected IDT descriptor is a valid type (interrupt, trap or task gate)
* if this was a software interrupt then gate DPL < CPL

The way we had structured the code meant that the privilege check for
software interrupts ended up not in the code path taken for task gate
handling, because all of the task gate handling code was in the 'case 5'
of the switch which was checking "is this descriptor a valid type".

Move the task gate handling code out of that switch (so that it is now
purely doing the "valid type?" check) and below the software interrupt
privilege check.

The effect of this missing check was that in a guest userspace binary
executing 'int 8' would cause a guest kernel panic rather than the
userspace binary being handed a SEGV.

This is essentially the same bug fixed in VirtualBox in 2012:
https://www.halfdog.net/Security/2012/VirtualBoxSoftwareInterrupt0x8GuestCrash/

Note that for QEMU this is not a security issue because it is only
present when using TCG.

Backports 3df1a3d070575419859cbbab1083fafa7ec2669a
2021-03-03 19:32:10 -05:00
bindings python: handle UC_ERR_TIMEOUT, so sample_x86.py behaves like sample_x86.c 2020-01-14 09:53:10 -05:00
docs docs: we no longer requires python2 in building 2020-01-14 09:07:44 -05:00
include Timeout error (#1173) 2020-01-14 09:42:57 -05:00
msvc msvc: Define CONFIG_TCG 2019-01-30 13:52:30 -05:00
qemu target/i386: Check privilege level for protected mode 'int N' task gate 2021-03-03 19:32:10 -05:00
samples Timeout error (#1173) 2020-01-14 09:42:57 -05:00
tests Tests, fixes on third platform. (#1168) 2020-01-14 09:45:55 -05:00
.appveyor.yml MSYS test (#852) 2017-06-25 10:11:35 +08:00
.gitignore target/riscv: Initial introduction of the RISC-V target 2019-03-08 21:46:10 -05:00
.travis.yml use new travis osx image and brew (#935) 2018-01-05 10:29:49 +08:00
AUTHORS.TXT import 2015-08-21 15:04:50 +08:00
Brewfile Update Brewfile 2017-09-30 17:36:44 +07:00
ChangeLog update ChangeLog 2017-04-20 13:28:02 +08:00
config.mk Fix document file extension 2016-08-08 17:33:49 +09:00
COPYING import 2015-08-21 15:04:50 +08:00
COPYING.LGPL2 LGPL2 for all header files under include/unicorn/ 2017-12-16 10:08:42 +08:00
COPYING_GLIB glib_compat: add COPYING_GLIB 2016-12-27 10:15:08 +08:00
CREDITS.TXT Adding Philippe Antoine to CREDITS 2018-10-06 04:50:10 -04:00
install-cmocka-linux.sh Start moving examples in S files (#851) 2017-06-25 10:14:22 +08:00
list.c callback to count number of instructions in uc_emu_start() should be executed first. fix #727 2017-06-16 13:22:38 +08:00
make.sh remove broken iOS builds (#1109) 2019-08-08 20:09:05 -04:00
Makefile uc: Restore armeb target 2019-04-19 15:29:25 -04:00
msvc.bat add msvc.bat 2017-04-21 15:35:40 +08:00
pkgconfig.mk bump extra version to 2 2017-04-21 15:30:40 +08:00
README.md add Clojure 2017-12-23 00:32:33 +08:00
uc.c Timeout error (#1173) 2020-01-14 09:42:57 -05:00
windows_export.bat Make the call out to visual studio extremely resilient 2017-01-02 03:32:48 -08:00

Unicorn Engine

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Build Status Build status

Unicorn is a lightweight, multi-platform, multi-architecture CPU emulator framework based on QEMU.

Unicorn offers some unparalleled features:

  • Multi-architecture: ARM, ARM64 (ARMv8), M68K, MIPS, SPARC, and X86 (16, 32, 64-bit)
  • Clean/simple/lightweight/intuitive architecture-neutral API
  • Implemented in pure C language, with bindings for Crystal, Clojure, Visual Basic, Perl, Rust, Ruby, Python, Java, .NET, Go, Delphi/Free Pascal and Haskell.
  • Native support for Windows & *nix (with Mac OSX, Linux, *BSD & Solaris confirmed)
  • High performance via Just-In-Time compilation
  • Support for fine-grained instrumentation at various levels
  • Thread-safety by design
  • Distributed under free software license GPLv2

Further information is available at http://www.unicorn-engine.org

License

This project is released under the GPL license.

Compilation & Docs

See docs/COMPILE.md file for how to compile and install Unicorn.

More documentation is available in docs/README.md.

Contact

Contact us via mailing list, email or twitter for any questions.

Contribute

If you want to contribute, please pick up something from our Github issues.

We also maintain a list of more challenged problems in a TODO list.

CREDITS.TXT records important contributors of our project.