From: Matthew Wilcox (Oracle) willy@infradead.org
commit c44aa5e8ab58b5f4cf473970ec784c3333496a2e upstream.
If you call xas_find() with the initial index > max, it should have returned NULL but was returning the entry at index.
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 | 5 +++++ lib/xarray.c | 10 ++++++++-- 2 files changed, 13 insertions(+), 2 deletions(-)
--- a/lib/test_xarray.c +++ b/lib/test_xarray.c @@ -2,6 +2,7 @@ /* * test_xarray.c: Test the XArray API * Copyright (c) 2017-2018 Microsoft Corporation + * Copyright (c) 2019-2020 Oracle * Author: Matthew Wilcox willy@infradead.org */
@@ -911,6 +912,7 @@ static noinline void check_multi_find_1(
xa_store_order(xa, multi, order, xa_mk_value(multi), GFP_KERNEL); XA_BUG_ON(xa, xa_store_index(xa, next, GFP_KERNEL) != NULL); + XA_BUG_ON(xa, xa_store_index(xa, next + 1, GFP_KERNEL) != NULL);
index = 0; XA_BUG_ON(xa, xa_find(xa, &index, ULONG_MAX, XA_PRESENT) != @@ -923,9 +925,12 @@ static noinline void check_multi_find_1( XA_BUG_ON(xa, xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT) != xa_mk_value(next)); XA_BUG_ON(xa, index != next); + XA_BUG_ON(xa, xa_find_after(xa, &index, next, XA_PRESENT) != NULL); + XA_BUG_ON(xa, index != next);
xa_erase_index(xa, multi); xa_erase_index(xa, next); + xa_erase_index(xa, next + 1); XA_BUG_ON(xa, !xa_empty(xa)); #endif } --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1,7 +1,8 @@ // SPDX-License-Identifier: GPL-2.0+ /* * XArray implementation - * Copyright (c) 2017 Microsoft Corporation + * Copyright (c) 2017-2018 Microsoft Corporation + * Copyright (c) 2018-2020 Oracle * Author: Matthew Wilcox willy@infradead.org */
@@ -1081,6 +1082,8 @@ void *xas_find(struct xa_state *xas, uns
if (xas_error(xas)) return NULL; + if (xas->xa_index > max) + return set_bounds(xas);
if (!xas->xa_node) { xas->xa_index = 1; @@ -1150,6 +1153,8 @@ void *xas_find_marked(struct xa_state *x
if (xas_error(xas)) return NULL; + if (xas->xa_index > max) + goto max;
if (!xas->xa_node) { xas->xa_index = 1; @@ -1867,7 +1872,8 @@ void *xa_find_after(struct xarray *xa, u entry = xas_find_marked(&xas, max, filter); else entry = xas_find(&xas, max); - if (xas.xa_node == XAS_BOUNDS) + + if (xas_invalid(&xas)) break; if (xas_sibling(&xas)) continue;