forked from Minki/linux
mainlining shenanigans
3ca9419227
Reported by syzkaller: WARNING: CPU: 0 PID: 6544 at /home/kernel/data/kvm/arch/x86/kvm//vmx/vmx.c:4689 handle_desc+0x37/0x40 [kvm_intel] CPU: 0 PID: 6544 Comm: a.out Tainted: G OE 5.3.0-rc4+ #4 RIP: 0010:handle_desc+0x37/0x40 [kvm_intel] Call Trace: vmx_handle_exit+0xbe/0x6b0 [kvm_intel] vcpu_enter_guest+0x4dc/0x18d0 [kvm] kvm_arch_vcpu_ioctl_run+0x407/0x660 [kvm] kvm_vcpu_ioctl+0x3ad/0x690 [kvm] do_vfs_ioctl+0xa2/0x690 ksys_ioctl+0x6d/0x80 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x74/0x720 entry_SYSCALL_64_after_hwframe+0x49/0xbe When CR4.UMIP is set, guest should have UMIP cpuid flag. Current kvm set_sregs function doesn't have such check when userspace inputs sregs values. SECONDARY_EXEC_DESC is enabled on writes to CR4.UMIP in vmx_set_cr4 though guest doesn't have UMIP cpuid flag. The testcast triggers handle_desc warning when executing ltr instruction since guest architectural CR4 doesn't set UMIP. This patch fixes it by adding valid CR4 and CPUID combination checking in __set_sregs. syzkaller source: https://syzkaller.appspot.com/x/repro.c?x=138efb99600000 Reported-by: syzbot+0f1819555fbdce992df9@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.