untrusted comment: verify with openbsd-78-base.pub
RWS3/nvFmk4SWVlP4nezURf6flQQ3h4uStOF9qtDsAkLJAuKWpKz4RPf40NZBiGPK56qSnRaAjaaUZME4kVc6RYkFI5eGZv6ewQ=

OpenBSD 7.8 errata 048, August 22, 2026:

The sysctl(2) kern.proc could leak kernel memory.

Apply by doing:
    signify -Vep /etc/signify/openbsd-78-base.pub -x 048_kernproc.patch.sig \
        -m - | (cd /usr/src && patch -p0)

And then rebuild and install a new kernel:
    KK=`sysctl -n kern.osversion | cut -d# -f1`
    cd /usr/src/sys/arch/`machine`/compile/$KK
    make obj
    make config
    make
    make install

Index: sys/uvm/uvm_io.c
===================================================================
RCS file: /cvs/src/sys/uvm/uvm_io.c,v
diff -u -p -r1.30 uvm_io.c
--- sys/uvm/uvm_io.c	7 Oct 2022 14:59:39 -0000	1.30
+++ sys/uvm/uvm_io.c	14 Aug 2026 17:02:23 -0000
@@ -74,7 +74,7 @@ uvm_io(vm_map_t map, struct uio *uio, in
 		return(EIO);
 
 	if (baseva >= VM_MAXUSER_ADDRESS)
-		return(0);
+		return (EIO);
 	if (endva >= VM_MAXUSER_ADDRESS)
 		/* EOF truncate */
 		togo = togo - (endva - VM_MAXUSER_ADDRESS + 1);