From: Matthew Wilcox (Oracle) willy@infradead.org
commit c36d451ad386b34f452fc3c8621ff14b9eaa31a6 upstream.
Inspired by the recent Coverity report, I looked for other places where the offset wasn't being converted to an unsigned long before being shifted, and I found one in xas_pause() when the entry being paused is of order >32.
Fixes: b803b42823d0 ("xarray: Add XArray iterators") Signed-off-by: Matthew Wilcox (Oracle) willy@infradead.org Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- lib/test_xarray.c | 37 +++++++++++++++++++++++++++++++++++++ lib/xarray.c | 2 +- 2 files changed, 38 insertions(+), 1 deletion(-)
--- a/lib/test_xarray.c +++ b/lib/test_xarray.c @@ -1156,6 +1156,42 @@ static noinline void check_find_entry(st XA_BUG_ON(xa, !xa_empty(xa)); }
+static noinline void check_pause(struct xarray *xa) +{ + XA_STATE(xas, xa, 0); + void *entry; + unsigned int order; + unsigned long index = 1; + unsigned int count = 0; + + for (order = 0; order < order_limit; order++) { + XA_BUG_ON(xa, xa_store_order(xa, index, order, + xa_mk_index(index), GFP_KERNEL)); + index += 1UL << order; + } + + rcu_read_lock(); + xas_for_each(&xas, entry, ULONG_MAX) { + XA_BUG_ON(xa, entry != xa_mk_index(1UL << count)); + count++; + } + rcu_read_unlock(); + XA_BUG_ON(xa, count != order_limit); + + count = 0; + xas_set(&xas, 0); + rcu_read_lock(); + xas_for_each(&xas, entry, ULONG_MAX) { + XA_BUG_ON(xa, entry != xa_mk_index(1UL << count)); + count++; + xas_pause(&xas); + } + rcu_read_unlock(); + XA_BUG_ON(xa, count != order_limit); + + xa_destroy(xa); +} + static noinline void check_move_tiny(struct xarray *xa) { XA_STATE(xas, xa, 0); @@ -1664,6 +1700,7 @@ static int xarray_checks(void) check_xa_alloc(); check_find(&array); check_find_entry(&array); + check_pause(&array); check_account(&array); check_destroy(&array); check_move(&array); --- a/lib/xarray.c +++ b/lib/xarray.c @@ -970,7 +970,7 @@ void xas_pause(struct xa_state *xas)
xas->xa_node = XAS_RESTART; if (node) { - unsigned int offset = xas->xa_offset; + unsigned long offset = xas->xa_offset; while (++offset < XA_CHUNK_SIZE) { if (!xa_is_sibling(xa_entry(xas->xa, node, offset))) break;