diff options
| -rw-r--r-- | sys/vm/vm_mmap.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/sys/vm/vm_mmap.c b/sys/vm/vm_mmap.c index 3fccd9e..90a2aaf 100644 --- a/sys/vm/vm_mmap.c +++ b/sys/vm/vm_mmap.c @@ -207,11 +207,23 @@ sys_mmap(td, uap) fp = NULL; - /* Make sure mapping fits into numeric range, etc. */ - if ((uap->len == 0 && !SV_CURPROC_FLAG(SV_AOUT) && - curproc->p_osrel >= P_OSREL_MAP_ANON) || - ((flags & MAP_ANON) && (uap->fd != -1 || pos != 0))) - return (EINVAL); + /* + * Enforce the constraints. + * Mapping of length 0 is only allowed for old binaries. + * Anonymous mapping shall specify -1 as filedescriptor and + * zero position for new code. Be nice to ancient a.out + * binaries and correct pos for anonymous mapping, since old + * ld.so sometimes issues anonymous map requests with non-zero + * pos. + */ + if (!SV_CURPROC_FLAG(SV_AOUT)) { + if ((uap->len == 0 && curproc->p_osrel >= P_OSREL_MAP_ANON) || + ((flags & MAP_ANON) != 0 && (uap->fd != -1 || pos != 0))) + return (EINVAL); + } else { + if ((flags & MAP_ANON) != 0) + pos = 0; + } if (flags & MAP_STACK) { if ((uap->fd != -1) || |
