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diff --git a/share/man/man9/copy.9 b/share/man/man9/copy.9
--- a/share/man/man9/copy.9
+++ b/share/man/man9/copy.9
@@ -32,15 +32,19 @@
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
-.Dd May 11, 2020
+.Dd December 19, 2025
.Dt COPY 9
.Os
.Sh NAME
.Nm copy ,
.Nm copyin ,
.Nm copyin_nofault ,
+.Nm copyinptr ,
+.Nm copyinptr_nofault ,
.Nm copyout ,
.Nm copyout_nofault ,
+.Nm copyoutptr ,
+.Nm copyoutptr_nofault ,
.Nm copystr ,
.Nm copyinstr
.Nd heterogeneous address space copy functions
@@ -52,9 +56,15 @@
.Ft int
.Fn copyin_nofault "const void *uaddr" "void *kaddr" "size_t len"
.Ft int
+.Fn copyinptr "const void *uaddr" "void *kaddr" "size_t len"
+.Ft int
.Fn copyout "const void *kaddr" "void *uaddr" "size_t len"
.Ft int
.Fn copyout_nofault "const void *kaddr" "void *uaddr" "size_t len"
+.Ft int
+.Fn copyoutptr "const void *kaddr" "void *uaddr" "size_t len"
+.Ft int
+.Fn copyoutptr_nofault "const void *kaddr" "void *uaddr" "size_t len"
.Ft int __deprecated
.Fn copystr "const void *kfaddr" "void *kdaddr" "size_t len" "size_t *done"
.Ft int
@@ -81,7 +91,12 @@
bytes of data from the user-space address
.Fa uaddr
to the kernel-space address
-.Fa kaddr .
+.Fa kaddr
+without preserving pointer provenance.
+The
+.Fn copyinptr
+function does the same,
+but preserve the provenance of copied pointers.
.Pp
The
.Fn copyout
@@ -92,7 +107,14 @@
bytes of data from the kernel-space address
.Fa kaddr
to the user-space address
-.Fa uaddr .
+.Fa uaddr
+without perservice pointer provenance.
+The
+.Fn copyoutptr
+and
+.Fn copyoutptr_nofault
+functions do the same,
+but preserve the provenance of copied pointers.
.Pp
The
.Fn copyin_nofault
@@ -105,6 +127,15 @@
destination addresses may be pageable.
.Pp
The
+.Fn copyinptr ,
+.Fn copyoutptr ,
+and
+.Fn copyoutptr_nofault
+functions must be used when copying data which may contain pointers,
+but they should only be used when necessary to limit the number of
+code paths that could leak pointers.
+.Pp
+The
.Fn copystr
function copies a NUL-terminated string, at most
.Fa len
diff --git a/sys/kern/subr_uio.c b/sys/kern/subr_uio.c
--- a/sys/kern/subr_uio.c
+++ b/sys/kern/subr_uio.c
@@ -88,6 +88,19 @@
return (error);
}
+#ifdef __CHERI__
+int
+copyoutptr_nofault(const void *kaddr, void *udaddr, size_t len)
+{
+ int error, save;
+
+ save = vm_fault_disable_pagefaults();
+ error = copyoutptr(kaddr, udaddr, len);
+ vm_fault_enable_pagefaults(save);
+ return (error);
+}
+#endif
+
#define PHYS_PAGE_COUNT(len) (howmany(len, PAGE_SIZE) + 1)
int
diff --git a/sys/sys/systm.h b/sys/sys/systm.h
--- a/sys/sys/systm.h
+++ b/sys/sys/systm.h
@@ -324,6 +324,22 @@
const void * _Nonnull __restrict kaddr, void * __restrict udaddr,
size_t len);
+#ifdef __CHERI__
+int __result_use_check copyinptr(const void * __restrict udaddr,
+ void * _Nonnull __restrict kaddr, size_t len);
+int __result_use_check copyoutptr(
+ const void * _Nonnull __restrict kaddr, void * __restrict udaddr,
+ size_t len);
+int __result_use_check copyoutptr_nofault(
+ const void * _Nonnull __restrict kaddr, void * __restrict udaddr,
+ size_t len);
+#else
+#define copyinptr copyin
+/* copyinptr_nofault not implemented due to no users */
+#define copyoutptr copyout
+#define copyoutptr_nofault copyout_nofault
+#endif
+
#ifdef SAN_NEEDS_INTERCEPTORS
int SAN_INTERCEPTOR(copyin)(const void *, void *, size_t);
int SAN_INTERCEPTOR(copyinstr)(const void *, void *, size_t, size_t *);

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