git: 42094ab41e5a - stable/15 - linux: correct errors from mremap(2)

The branch stable/15 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=42094ab41e5ad34b56603fa343ba53f93c7f4984

commit 42094ab41e5ad34b56603fa343ba53f93c7f4984
Author:     Joy <amutu@amutu.com>
AuthorDate: 2026-10-24 02:22:29 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-10-31 03:15:21 +0000

    linux: correct errors from mremap(2)
    
    PR:     299835
    
    (cherry picked from commit 9a8d5af1ba0174ec5fcc3eedba545aec9a627987)
---
 sys/compat/linux/linux_misc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/sys/compat/linux/linux_misc.c b/sys/compat/linux/linux_misc.c
index de40449e6f15..604453e48285 100644
--- a/sys/compat/linux/linux_misc.c
+++ b/sys/compat/linux/linux_misc.c
@@ -62,6 +62,7 @@
 #include <security/mac/mac_framework.h>
 
 #include <vm/pmap.h>
+#include <vm/vm_extern.h>
 #include <vm/vm_map.h>
 #include <vm/swap_pager.h>
 
@@ -325,7 +326,10 @@ linux_mremap(struct thread *td, struct linux_mremap_args *args)
 
 	if (args->new_len > args->old_len) {
 		td->td_retval[0] = 0;
-		return (ENOMEM);
+		if (useracc((void *)(uintptr_t)args->addr, args->old_len,
+		    VM_PROT_READ))
+			return (ENOMEM);
+		return (EFAULT);
 	}
 
 	if (args->new_len < args->old_len) {