diff options
| author | Theo de Raadt <deraadt@cvs.openbsd.org> | 2022-10-24 15:11:57 +0000 |
|---|---|---|
| committer | Theo de Raadt <deraadt@cvs.openbsd.org> | 2022-10-24 15:11:57 +0000 |
| commit | 492d6afd13b0c019785cb2b706d636ece0d4765e (patch) | |
| tree | 4ac441d50b990a857b0a41c50ab8cda2d6399739 /sys/uvm | |
| parent | 448bd1ad13b26e84b04b29cb4d71276db5e8a5a5 (diff) | |
uvm_unmap_remove() traverses the entries in the start,end range scanning
for IMMUTABLE, before traversing for unmap. I didn't copy enough traversal
code for the scan, and thus MAP_FIXED was subtly broken.
test help from tb, ok kettenis miod
Diffstat (limited to 'sys/uvm')
| -rw-r--r-- | sys/uvm/uvm_map.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/sys/uvm/uvm_map.c b/sys/uvm/uvm_map.c index 130c57b4b24..67749c5c4b3 100644 --- a/sys/uvm/uvm_map.c +++ b/sys/uvm/uvm_map.c @@ -1,4 +1,4 @@ -/* $OpenBSD: uvm_map.c,v 1.300 2022/10/21 20:45:51 deraadt Exp $ */ +/* $OpenBSD: uvm_map.c,v 1.301 2022/10/24 15:11:56 deraadt Exp $ */ /* $NetBSD: uvm_map.c,v 1.86 2000/11/27 08:40:03 chs Exp $ */ /* @@ -2009,9 +2009,14 @@ uvm_unmap_remove(struct vm_map *map, vaddr_t start, vaddr_t end, struct vm_map_entry *entry1 = entry; /* Refuse to unmap if any entries are immutable */ + if (entry1->end <= start) + entry1 = RBT_NEXT(uvm_map_addr, entry1); for (; entry1 != NULL && entry1->start < end; entry1 = next) { KDASSERT(entry1->start >= start); next = RBT_NEXT(uvm_map_addr, entry1); + /* Treat memory holes as free space. */ + if (entry1->start == entry1->end || UVM_ET_ISHOLE(entry1)) + continue; if (entry1->etype & UVM_ET_IMMUTABLE) return EPERM; } @@ -3141,11 +3146,7 @@ uvm_map_protect(struct vm_map *map, vaddr_t start, vaddr_t end, (iter->etype & UVM_ET_IMMUTABLE)) { if (iter->protection == (PROT_READ | PROT_WRITE) && new_prot == PROT_READ) { - /* - * XXX chrome renderer on 2022oct21 does a - * RW->R transition of some immutable range. - * Workaround this until it is found... - */ + /* Permit RW to R as a data-locking mechanism */ ; } else { error = EPERM; |