diff options
Diffstat (limited to 'sys/vm/vm_glue.c')
| -rw-r--r-- | sys/vm/vm_glue.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/sys/vm/vm_glue.c b/sys/vm/vm_glue.c index 22091d772737f..71bcb7c67c4b4 100644 --- a/sys/vm/vm_glue.c +++ b/sys/vm/vm_glue.c @@ -59,7 +59,7 @@ * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. * - * $Id: vm_glue.c,v 1.55.2.1 1996/12/22 23:21:25 joerg Exp $ + * $Id: vm_glue.c,v 1.55.2.2 1997/02/13 08:17:31 bde Exp $ */ #include "opt_rlimit.h" @@ -126,7 +126,9 @@ kernacc(addr, len, rw) saddr = trunc_page(addr); eaddr = round_page(addr + len); + vm_map_lock_read(kernel_map); rv = vm_map_check_protection(kernel_map, saddr, eaddr, prot); + vm_map_unlock_read(kernel_map); return (rv == TRUE); } @@ -137,6 +139,8 @@ useracc(addr, len, rw) { boolean_t rv; vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE; + vm_map_t map; + vm_map_entry_t save_hint; /* * XXX - check separately to disallow access to user area and user @@ -151,8 +155,18 @@ useracc(addr, len, rw) || (vm_offset_t) addr + len < (vm_offset_t) addr) { return (FALSE); } - rv = vm_map_check_protection(&curproc->p_vmspace->vm_map, + map = &curproc->p_vmspace->vm_map; + vm_map_lock_read(map); + /* + * We save the map hint, and restore it. Useracc appears to distort + * the map hint unnecessarily. + */ + save_hint = map->hint; + rv = vm_map_check_protection(map, trunc_page(addr), round_page(addr + len), prot); + map->hint = save_hint; + vm_map_unlock_read(map); + return (rv == TRUE); } |