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: a7800aa ("KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memory") Cc: [email protected] Reviewed-by: Liam Merwick <[email protected]> Reviewed-by: Isaku Yamahata <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
wafgo · Jun 20, 2024 · c31745d · c31745d
1 parent f474092
commit c31745d
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
@@ -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);