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| author | Jan Kiszka <jan.kiszka@web.de> | 2009-07-02 21:45:47 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2009-08-05 13:58:03 +0300 |
| commit | e125e7b6944898831b56739a5448e705578bf7e2 (patch) | |
| tree | 27bdf220e2bedfd20358627563509089e8584003 /arch/x86/kvm/x86.c | |
| parent | 90bc1a658a53f8832ee799685703977a450e5af9 (diff) | |
| download | lwn-e125e7b6944898831b56739a5448e705578bf7e2.tar.gz lwn-e125e7b6944898831b56739a5448e705578bf7e2.zip | |
KVM: Fix KVM_GET_MSR_INDEX_LIST
So far, KVM copied the emulated_msrs (only MSR_IA32_MISC_ENABLE) to a
wrong address in user space due to broken pointer arithmetic. This
caused subtle corruption up there (missing MSR_IA32_MISC_ENABLE had
probably no practical relevance). Moreover, the size check for the
user-provided kvm_msr_list forgot about emulated MSRs.
Cc: stable@kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/x86/kvm/x86.c')
| -rw-r--r-- | arch/x86/kvm/x86.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index fe5474aec41a..7bc311464fae 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1079,14 +1079,13 @@ long kvm_arch_dev_ioctl(struct file *filp, if (copy_to_user(user_msr_list, &msr_list, sizeof msr_list)) goto out; r = -E2BIG; - if (n < num_msrs_to_save) + if (n < msr_list.nmsrs) goto out; r = -EFAULT; if (copy_to_user(user_msr_list->indices, &msrs_to_save, num_msrs_to_save * sizeof(u32))) goto out; - if (copy_to_user(user_msr_list->indices - + num_msrs_to_save * sizeof(u32), + if (copy_to_user(user_msr_list->indices + num_msrs_to_save, &emulated_msrs, ARRAY_SIZE(emulated_msrs) * sizeof(u32))) goto out; |