bcache: Fix bch_ptr_bad()

Previously, bch_ptr_bad() could return false when there was a pointer to
a nonexistant device... it only filtered out keys with PTR_CHECK_DEV
pointers.

This behaviour was intended for multiple cache device support; for that,
just because the device for one of the pointers has gone away doesn't
mean we want to filter out the rest of the pointers.

But we don't yet explicitly filter/check individual pointers, so without
that this behaviour was wrong - a corrupt bkey with a bad device pointer
could cause us to deref a bad pointer. Doh.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This commit is contained in:
Kent Overstreet 2013-07-24 18:14:44 -07:00
parent 81ab4190ac
commit e58ff15503

View File

@ -116,47 +116,46 @@ bool bch_ptr_bad(struct btree *b, const struct bkey *k)
bch_ptr_invalid(b, k))
return true;
if (KEY_PTRS(k) && PTR_DEV(k, 0) == PTR_CHECK_DEV)
return true;
for (i = 0; i < KEY_PTRS(k); i++) {
if (!ptr_available(b->c, k, i))
return true;
for (i = 0; i < KEY_PTRS(k); i++)
if (ptr_available(b->c, k, i)) {
g = PTR_BUCKET(b->c, k, i);
stale = ptr_stale(b->c, k, i);
g = PTR_BUCKET(b->c, k, i);
stale = ptr_stale(b->c, k, i);
btree_bug_on(stale > 96, b,
"key too stale: %i, need_gc %u",
stale, b->c->need_gc);
btree_bug_on(stale > 96, b,
"key too stale: %i, need_gc %u",
stale, b->c->need_gc);
btree_bug_on(stale && KEY_DIRTY(k) && KEY_SIZE(k),
b, "stale dirty pointer");
btree_bug_on(stale && KEY_DIRTY(k) && KEY_SIZE(k),
b, "stale dirty pointer");
if (stale)
return true;
if (stale)
return true;
#ifdef CONFIG_BCACHE_EDEBUG
if (!mutex_trylock(&b->c->bucket_lock))
continue;
if (!mutex_trylock(&b->c->bucket_lock))
continue;
if (b->level) {
if (KEY_DIRTY(k) ||
g->prio != BTREE_PRIO ||
(b->c->gc_mark_valid &&
GC_MARK(g) != GC_MARK_METADATA))
goto bug;
if (b->level) {
if (KEY_DIRTY(k) ||
g->prio != BTREE_PRIO ||
(b->c->gc_mark_valid &&
GC_MARK(g) != GC_MARK_METADATA))
goto bug;
} else {
if (g->prio == BTREE_PRIO)
goto bug;
} else {
if (g->prio == BTREE_PRIO)
goto bug;
if (KEY_DIRTY(k) &&
b->c->gc_mark_valid &&
GC_MARK(g) != GC_MARK_DIRTY)
goto bug;
}
mutex_unlock(&b->c->bucket_lock);
#endif
if (KEY_DIRTY(k) &&
b->c->gc_mark_valid &&
GC_MARK(g) != GC_MARK_DIRTY)
goto bug;
}
mutex_unlock(&b->c->bucket_lock);
#endif
}
return false;
#ifdef CONFIG_BCACHE_EDEBUG