From c44aa5e8ab58b5f4cf473970ec784c3333496a2e Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Fri, 17 Jan 2020 22:13:21 -0500 Subject: XArray: Fix xas_find returning too many entries 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) Cc: stable@vger.kernel.org --- lib/test_xarray.c | 5 +++++ lib/xarray.c | 10 ++++++++-- 2 files changed, 13 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/test_xarray.c b/lib/test_xarray.c index c8cc97ded0fa..55c14e8c8859 100644 --- 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 */ @@ -911,6 +912,7 @@ static noinline void check_multi_find_1(struct xarray *xa, unsigned order) 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(struct xarray *xa, unsigned order) 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 } diff --git a/lib/xarray.c b/lib/xarray.c index 03300a0d6425..1d9fab7db8da 100644 --- 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 */ @@ -1083,6 +1084,8 @@ void *xas_find(struct xa_state *xas, unsigned long max) if (xas_error(xas) || xas->xa_node == XAS_BOUNDS) return NULL; + if (xas->xa_index > max) + return set_bounds(xas); if (!xas->xa_node) { xas->xa_index = 1; @@ -1152,6 +1155,8 @@ void *xas_find_marked(struct xa_state *xas, unsigned long max, xa_mark_t mark) if (xas_error(xas)) return NULL; + if (xas->xa_index > max) + goto max; if (!xas->xa_node) { xas->xa_index = 1; @@ -1869,7 +1874,8 @@ void *xa_find_after(struct xarray *xa, unsigned long *indexp, 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; -- cgit v1.2.3-59-g8ed1b