[ Upstream commit b86bc2858b389255cd44555ce4b1e427b2b770c0 ]
This ensures that the address and length provided to DBG_DECRYPT and
DBG_ENCRYPT do not cause an overflow.
At the same time, pass the actual number of pages pinned in memory to
sev_unpin_memory() as a cleanup.
Reported-by: Cfir Cohen <c...@google.com>
Signed-off-by: David Rientjes <rient...@google.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
Signed-off-by: Sasha Levin (Microsoft) <sas...@kernel.org>
---
arch/x86/kvm/svm.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index e544cec812f9..2a07e43ee666 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6815,7 +6815,8 @@ static int sev_dbg_crypt(struct kvm *kvm, struct
kvm_sev_cmd *argp, bool dec)
struct page **src_p, **dst_p;
struct kvm_sev_dbg debug;
unsigned long n;
- int ret, size;
+ unsigned int size;
+ int ret;
if (!sev_guest(kvm))
return -ENOTTY;
@@ -6823,6 +6824,11 @@ static int sev_dbg_crypt(struct kvm *kvm, struct
kvm_sev_cmd *argp, bool dec)
if (copy_from_user(&debug, (void __user *)(uintptr_t)argp->data,
sizeof(debug)))
return -EFAULT;
+ if (!debug.len || debug.src_uaddr + debug.len < debug.src_uaddr)
+ return -EINVAL;
+ if (!debug.dst_uaddr)
+ return -EINVAL;
+
vaddr = debug.src_uaddr;
size = debug.len;
vaddr_end = vaddr + size;
@@ -6873,8 +6879,8 @@ static int sev_dbg_crypt(struct kvm *kvm, struct
kvm_sev_cmd *argp, bool dec)
dst_vaddr,
len, &argp->error);
- sev_unpin_memory(kvm, src_p, 1);
- sev_unpin_memory(kvm, dst_p, 1);
+ sev_unpin_memory(kvm, src_p, n);
+ sev_unpin_memory(kvm, dst_p, n);
if (ret)
goto err;
--
2.20.1
