virt: guest_memfd: fix reference leak on hwpoisoned page

If kvm_gmem_get_pfn() detects an hwpoisoned page, it returns -EHWPOISON
but it does not put back the reference that kvm_gmem_get_folio() had
grabbed.  Add the forgotten folio_put().

Fixes: a7800aa80e ("KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memory")
Cc: stable@vger.kernel.org
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2024-06-11 04:22:18 -04:00
parent f474092c6f
commit c31745d2c5

View File

@ -510,8 +510,10 @@ int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot,
}
if (folio_test_hwpoison(folio)) {
folio_unlock(folio);
folio_put(folio);
r = -EHWPOISON;
goto out_unlock;
goto out_fput;
}
page = folio_file_page(folio, index);
@ -522,7 +524,6 @@ int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot,
r = 0;
out_unlock:
folio_unlock(folio);
out_fput:
fput(file);