git: 75bf78a0ed8d - stable/15 - kern/sys_process.c: make vmspace_rwmem() similar to io functions

The branch stable/15 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=75bf78a0ed8d3e108532c8893f5dad8bdb2b0b3e

commit 75bf78a0ed8d3e108532c8893f5dad8bdb2b0b3e
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2026-08-14 05:46:07 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-08-16 02:41:19 +0000

    kern/sys_process.c: make vmspace_rwmem() similar to io functions
    
    PR:     297512
    
    (cherry picked from commit 1a71d24ecd0dbaf61fd2a44166e9be07c328b198)
---
 sys/kern/sys_process.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c
index 9ba8ec33e5dc..a365f833b2af 100644
--- a/sys/kern/sys_process.c
+++ b/sys/kern/sys_process.c
@@ -418,6 +418,7 @@ vmspace_rwmem(struct vmspace *vm, struct uio *uio)
 	vm_map_t map;
 	vm_offset_t pageno;		/* page number */
 	vm_prot_t reqprot;
+	ssize_t orig_resid;
 	int error, fault_flags, page_offset, writing;
 
 	map = &vm->vm_map;
@@ -431,10 +432,12 @@ vmspace_rwmem(struct vmspace *vm, struct uio *uio)
 	reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ;
 	fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL;
 
+	orig_resid = uio->uio_resid;
+
 	if (writing) {
 		error = priv_check(curthread, PRIV_PROC_MEM_WRITE);
 		if (error != 0)
-			goto out;
+			return (error);
 	}
 
 	/*
@@ -491,9 +494,7 @@ vmspace_rwmem(struct vmspace *vm, struct uio *uio)
 		vm_page_unwire(m, PQ_ACTIVE);
 
 	} while (error == 0 && uio->uio_resid > 0);
-
-out:
-	return (error);
+	return (uio->uio_resid == orig_resid ? error : 0);
 }
 
 int