From: "Liam R. Howlett" <Liam.Howlett@oracle.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, stable@vger.kernel.org
Cc: maple-tree@lists.infradead.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org,
"Liam R. Howlett" <Liam.Howlett@Oracle.com>,
Stable@vger.kernel.org, Liam Howlett <Liam.Howlett@oracle.com>
Subject: [PATCH 6.1 07/14] maple_tree: be more cautious about dead nodes
Date: Tue, 11 Apr 2023 11:10:48 -0400 [thread overview]
Message-ID: <20230411151055.2910579-8-Liam.Howlett@oracle.com> (raw)
In-Reply-To: <20230411151055.2910579-1-Liam.Howlett@oracle.com>
From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
commit 39d0bd86c499ecd6abae42a9b7112056c5560691 upstream.
ma_pivots() and ma_data_end() may be called with a dead node. Ensure to
that the node isn't dead before using the returned values.
This is necessary for RCU mode of the maple tree.
Link: https://lkml.kernel.org/r/20230227173632.3292573-1-surenb@google.com
Link: https://lkml.kernel.org/r/20230227173632.3292573-2-surenb@google.com
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Liam Howlett <Liam.Howlett@oracle.com>
---
lib/maple_tree.c | 52 +++++++++++++++++++++++++++++++++++++++---------
1 file changed, 43 insertions(+), 9 deletions(-)
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index c50646fcb8ca..7c8225e7df13 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -534,6 +534,7 @@ static inline bool ma_dead_node(const struct maple_node *node)
return (parent == node);
}
+
/*
* mte_dead_node() - check if the @enode is dead.
* @enode: The encoded maple node
@@ -615,6 +616,8 @@ static inline unsigned int mas_alloc_req(const struct ma_state *mas)
* @node - the maple node
* @type - the node type
*
+ * In the event of a dead node, this array may be %NULL
+ *
* Return: A pointer to the maple node pivots
*/
static inline unsigned long *ma_pivots(struct maple_node *node,
@@ -1086,8 +1089,11 @@ static int mas_ascend(struct ma_state *mas)
a_type = mas_parent_enum(mas, p_enode);
a_node = mte_parent(p_enode);
a_slot = mte_parent_slot(p_enode);
- pivots = ma_pivots(a_node, a_type);
a_enode = mt_mk_node(a_node, a_type);
+ pivots = ma_pivots(a_node, a_type);
+
+ if (unlikely(ma_dead_node(a_node)))
+ return 1;
if (!set_min && a_slot) {
set_min = true;
@@ -1393,6 +1399,9 @@ static inline unsigned char ma_data_end(struct maple_node *node,
{
unsigned char offset;
+ if (!pivots)
+ return 0;
+
if (type == maple_arange_64)
return ma_meta_end(node, type);
@@ -1428,6 +1437,9 @@ static inline unsigned char mas_data_end(struct ma_state *mas)
return ma_meta_end(node, type);
pivots = ma_pivots(node, type);
+ if (unlikely(ma_dead_node(node)))
+ return 0;
+
offset = mt_pivots[type] - 1;
if (likely(!pivots[offset]))
return ma_meta_end(node, type);
@@ -4499,6 +4511,9 @@ static inline int mas_prev_node(struct ma_state *mas, unsigned long min)
node = mas_mn(mas);
slots = ma_slots(node, mt);
pivots = ma_pivots(node, mt);
+ if (unlikely(ma_dead_node(node)))
+ return 1;
+
mas->max = pivots[offset];
if (offset)
mas->min = pivots[offset - 1] + 1;
@@ -4520,6 +4535,9 @@ static inline int mas_prev_node(struct ma_state *mas, unsigned long min)
slots = ma_slots(node, mt);
pivots = ma_pivots(node, mt);
offset = ma_data_end(node, mt, pivots, mas->max);
+ if (unlikely(ma_dead_node(node)))
+ return 1;
+
if (offset)
mas->min = pivots[offset - 1] + 1;
@@ -4568,6 +4586,7 @@ static inline int mas_next_node(struct ma_state *mas, struct maple_node *node,
struct maple_enode *enode;
int level = 0;
unsigned char offset;
+ unsigned char node_end;
enum maple_type mt;
void __rcu **slots;
@@ -4591,7 +4610,11 @@ static inline int mas_next_node(struct ma_state *mas, struct maple_node *node,
node = mas_mn(mas);
mt = mte_node_type(mas->node);
pivots = ma_pivots(node, mt);
- } while (unlikely(offset == ma_data_end(node, mt, pivots, mas->max)));
+ node_end = ma_data_end(node, mt, pivots, mas->max);
+ if (unlikely(ma_dead_node(node)))
+ return 1;
+
+ } while (unlikely(offset == node_end));
slots = ma_slots(node, mt);
pivot = mas_safe_pivot(mas, pivots, ++offset, mt);
@@ -4607,6 +4630,9 @@ static inline int mas_next_node(struct ma_state *mas, struct maple_node *node,
mt = mte_node_type(mas->node);
slots = ma_slots(node, mt);
pivots = ma_pivots(node, mt);
+ if (unlikely(ma_dead_node(node)))
+ return 1;
+
offset = 0;
pivot = pivots[0];
}
@@ -4653,11 +4679,14 @@ static inline void *mas_next_nentry(struct ma_state *mas,
return NULL;
}
- pivots = ma_pivots(node, type);
slots = ma_slots(node, type);
- mas->index = mas_safe_min(mas, pivots, mas->offset);
+ pivots = ma_pivots(node, type);
count = ma_data_end(node, type, pivots, mas->max);
- if (ma_dead_node(node))
+ if (unlikely(ma_dead_node(node)))
+ return NULL;
+
+ mas->index = mas_safe_min(mas, pivots, mas->offset);
+ if (unlikely(ma_dead_node(node)))
return NULL;
if (mas->index > max)
@@ -4815,6 +4844,11 @@ static inline void *mas_prev_nentry(struct ma_state *mas, unsigned long limit,
slots = ma_slots(mn, mt);
pivots = ma_pivots(mn, mt);
+ if (unlikely(ma_dead_node(mn))) {
+ mas_rewalk(mas, index);
+ goto retry;
+ }
+
if (offset == mt_pivots[mt])
pivot = mas->max;
else
@@ -6617,11 +6651,11 @@ static inline void *mas_first_entry(struct ma_state *mas, struct maple_node *mn,
while (likely(!ma_is_leaf(mt))) {
MT_BUG_ON(mas->tree, mte_dead_node(mas->node));
slots = ma_slots(mn, mt);
- pivots = ma_pivots(mn, mt);
- max = pivots[0];
entry = mas_slot(mas, slots, 0);
+ pivots = ma_pivots(mn, mt);
if (unlikely(ma_dead_node(mn)))
return NULL;
+ max = pivots[0];
mas->node = entry;
mn = mas_mn(mas);
mt = mte_node_type(mas->node);
@@ -6641,13 +6675,13 @@ static inline void *mas_first_entry(struct ma_state *mas, struct maple_node *mn,
if (likely(entry))
return entry;
- pivots = ma_pivots(mn, mt);
- mas->index = pivots[0] + 1;
mas->offset = 1;
entry = mas_slot(mas, slots, 1);
+ pivots = ma_pivots(mn, mt);
if (unlikely(ma_dead_node(mn)))
return NULL;
+ mas->index = pivots[0] + 1;
if (mas->index > limit)
goto none;
--
2.39.2
next prev parent reply other threads:[~2023-04-11 15:11 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-11 15:10 [PATCH 6.1 00/14] Backport of maple tree fixes for 6.1/6.2 Liam R. Howlett
2023-04-11 15:10 ` [PATCH 6.1 01/14] maple_tree: remove GFP_ZERO from kmem_cache_alloc() and kmem_cache_alloc_bulk() Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: remove GFP_ZERO from kmem_cache_alloc() and kmem_cache_alloc_bulk()" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: remove GFP_ZERO from kmem_cache_alloc() and kmem_cache_alloc_bulk()" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 02/14] maple_tree: fix potential rcu issue Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: fix potential rcu issue" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: fix potential rcu issue" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 03/14] maple_tree: reduce user error potential Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: reduce user error potential" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: reduce user error potential" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 04/14] maple_tree: fix handle of invalidated state in mas_wr_store_setup() Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: fix handle of invalidated state in mas_wr_store_setup()" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: fix handle of invalidated state in mas_wr_store_setup()" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 05/14] maple_tree: fix mas_prev() and mas_find() state handling Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: fix mas_prev() and mas_find() state handling" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: fix mas_prev() and mas_find() state handling" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 06/14] maple_tree: fix mas_skip_node() end slot detection Liam R. Howlett
2023-04-11 15:10 ` Liam R. Howlett [this message]
2023-04-12 8:12 ` Patch "maple_tree: be more cautious about dead nodes" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: be more cautious about dead nodes" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 08/14] maple_tree: refine ma_state init from mas_start() Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: refine ma_state init from mas_start()" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: refine ma_state init from mas_start()" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 09/14] maple_tree: detect dead nodes in mas_start() Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: detect dead nodes in mas_start()" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: detect dead nodes in mas_start()" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 10/14] maple_tree: fix freeing of nodes in rcu mode Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: fix freeing of nodes in rcu mode" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: fix freeing of nodes in rcu mode" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 11/14] maple_tree: remove extra smp_wmb() from mas_dead_leaves() Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: remove extra smp_wmb() from mas_dead_leaves()" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: remove extra smp_wmb() from mas_dead_leaves()" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 12/14] maple_tree: add smp_rmb() to dead node detection Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: add smp_rmb() to dead node detection" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: add smp_rmb() to dead node detection" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 13/14] maple_tree: add RCU lock checking to rcu callback functions Liam R. Howlett
2023-04-12 8:12 ` Patch "maple_tree: add RCU lock checking to rcu callback functions" has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "maple_tree: add RCU lock checking to rcu callback functions" has been added to the 6.1-stable tree gregkh
2023-04-11 15:10 ` [PATCH 6.1 14/14] mm: enable maple tree RCU mode by default Liam R. Howlett
2023-04-12 8:12 ` Patch "mm: enable maple tree RCU mode by default." has been added to the 6.2-stable tree gregkh
2023-04-12 8:13 ` Patch "mm: enable maple tree RCU mode by default." has been added to the 6.1-stable tree gregkh
2023-04-12 8:12 ` [PATCH 6.1 00/14] Backport of maple tree fixes for 6.1/6.2 Greg Kroah-Hartman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230411151055.2910579-8-Liam.Howlett@oracle.com \
--to=liam.howlett@oracle.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=maple-tree@lists.infradead.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).