diff options
| author | Martin Pieuchot <mpi@cvs.openbsd.org> | 2024-04-16 08:53:03 +0000 |
|---|---|---|
| committer | Martin Pieuchot <mpi@cvs.openbsd.org> | 2024-04-16 08:53:03 +0000 |
| commit | 24fa894f29740c8b4143233f6003dc9d28834169 (patch) | |
| tree | 12fb671a8166ccba12f0b44ced00c3a4ef00615c /sys | |
| parent | 1dff650f39a64387f01ee36fe46137289f99bce2 (diff) | |
Prevent a NULL dereference in error code path.
Under memory pressure allocating an amap chunk can fail. In such case it
is not possible to call amap_wipeout() because the newly allocated amap
isn't yet on the global list.
Issue reported by bluhm@, ok jsg@
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/uvm/uvm_amap.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/sys/uvm/uvm_amap.c b/sys/uvm/uvm_amap.c index 63dc8534081..fb85a3c91a8 100644 --- a/sys/uvm/uvm_amap.c +++ b/sys/uvm/uvm_amap.c @@ -1,4 +1,4 @@ -/* $OpenBSD: uvm_amap.c,v 1.92 2023/04/11 00:45:09 jsg Exp $ */ +/* $OpenBSD: uvm_amap.c,v 1.93 2024/04/16 08:53:02 mpi Exp $ */ /* $NetBSD: uvm_amap.c,v 1.27 2000/11/25 06:27:59 chs Exp $ */ /* @@ -662,9 +662,10 @@ amap_copy(struct vm_map *map, struct vm_map_entry *entry, int waitf, chunk = amap_chunk_get(amap, lcv, 1, PR_NOWAIT); if (chunk == NULL) { - /* amap_wipeout() releases the lock. */ - amap->am_ref = 0; - amap_wipeout(amap); + amap_unlock(srcamap); + /* Destroy the new amap. */ + amap->am_ref--; + amap_free(amap); return; } |