This is a note to let you know that I've just added the patch titled maple_tree: fix mas_prev() and mas_find() state handling to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: maple_tree-fix-mas_prev-and-mas_find-state-handling.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From stable-owner@xxxxxxxxxxxxxxx Tue Apr 11 17:13:01 2023 From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx> Date: Tue, 11 Apr 2023 11:10:46 -0400 Subject: maple_tree: fix mas_prev() and mas_find() state handling To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>, stable@xxxxxxxxxxxxxxx Cc: maple-tree@xxxxxxxxxxxxxxxxxxx, linux-mm@xxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>, Stable@xxxxxxxxxxxxxxx, "Liam R . Howlett" <Liam.Howlett@xxxxxxxxxx>, syzbot+502859d610c661e56545@xxxxxxxxxxxxxxxxxxxxxxxxx Message-ID: <20230411151055.2910579-6-Liam.Howlett@xxxxxxxxxx> From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx> commit 17dc622c7b0f94e49bed030726df4db12ecaa6b5 upstream. When mas_prev() does not find anything, set the state to MAS_NONE. Handle the MAS_NONE in mas_find() like a MAS_START. Link: https://lkml.kernel.org/r/20230120162650.984577-7-Liam.Howlett@xxxxxxxxxx Cc: <Stable@xxxxxxxxxxxxxxx> Fixes: 54a611b60590 ("Maple Tree: add new data structure") Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> Reported-by: <syzbot+502859d610c661e56545@xxxxxxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- lib/maple_tree.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -4844,7 +4844,7 @@ static inline void *mas_prev_entry(struc if (mas->index < min) { mas->index = mas->last = min; - mas_pause(mas); + mas->node = MAS_NONE; return NULL; } retry: @@ -5906,6 +5906,7 @@ void *mas_prev(struct ma_state *mas, uns if (!mas->index) { /* Nothing comes before 0 */ mas->last = 0; + mas->node = MAS_NONE; return NULL; } @@ -5996,6 +5997,9 @@ void *mas_find(struct ma_state *mas, uns mas->index = ++mas->last; } + if (unlikely(mas_is_none(mas))) + mas->node = MAS_START; + if (unlikely(mas_is_start(mas))) { /* First run or continue */ void *entry; Patches currently in stable-queue which might be from stable-owner@xxxxxxxxxxxxxxx are queue-6.1/maple_tree-fix-potential-rcu-issue.patch queue-6.1/maple_tree-add-smp_rmb-to-dead-node-detection.patch queue-6.1/maple_tree-add-rcu-lock-checking-to-rcu-callback-functions.patch queue-6.1/maple_tree-fix-handle-of-invalidated-state-in-mas_wr_store_setup.patch queue-6.1/maple_tree-reduce-user-error-potential.patch queue-6.1/maple_tree-fix-mas_prev-and-mas_find-state-handling.patch queue-6.1/maple_tree-remove-gfp_zero-from-kmem_cache_alloc-and-kmem_cache_alloc_bulk.patch queue-6.1/maple_tree-be-more-cautious-about-dead-nodes.patch queue-6.1/mm-enable-maple-tree-rcu-mode-by-default.patch queue-6.1/maple_tree-detect-dead-nodes-in-mas_start.patch queue-6.1/maple_tree-fix-freeing-of-nodes-in-rcu-mode.patch queue-6.1/maple_tree-remove-extra-smp_wmb-from-mas_dead_leaves.patch queue-6.1/maple_tree-refine-ma_state-init-from-mas_start.patch