The patch titled Subject: maple_tree: fix potential out-of-bounds access in mas_wr_end_piv() has been added to the -mm mm-unstable branch. Its filename is maple_tree-fix-potential-out-of-bounds-access-in-mas_wr_end_piv.patch
This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...
This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days
------------------------------------------------------ From: Peng Zhang zhangpeng.00@bytedance.com Subject: maple_tree: fix potential out-of-bounds access in mas_wr_end_piv() Date: Sat, 6 May 2023 10:47:52 +0800
Check the write offset end bounds before using it as the offset into the pivot array. This avoids a possible out-of-bounds access on the pivot array if the write extends to the last slot in the node, in which case the node maximum should be used as the end pivot.
akpm: this doesn't affect any current callers, but new users of mapletree may encounter this problem if backported into earlier kernels, so let's fix it in -stable kernels in case of this.
Link: https://lkml.kernel.org/r/20230506024752.2550-1-zhangpeng.00@bytedance.com Fixes: 54a611b60590 ("Maple Tree: add new data structure") Signed-off-by: Peng Zhang zhangpeng.00@bytedance.com Reviewed-by: Liam R. Howlett Liam.Howlett@oracle.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
lib/maple_tree.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)
--- a/lib/maple_tree.c~maple_tree-fix-potential-out-of-bounds-access-in-mas_wr_end_piv +++ a/lib/maple_tree.c @@ -4262,11 +4262,13 @@ done:
static inline void mas_wr_end_piv(struct ma_wr_state *wr_mas) { - while ((wr_mas->mas->last > wr_mas->end_piv) && - (wr_mas->offset_end < wr_mas->node_end)) - wr_mas->end_piv = wr_mas->pivots[++wr_mas->offset_end]; + while ((wr_mas->offset_end < wr_mas->node_end) && + (wr_mas->mas->last > wr_mas->pivots[wr_mas->offset_end])) + wr_mas->offset_end++;
- if (wr_mas->mas->last > wr_mas->end_piv) + if (wr_mas->offset_end < wr_mas->node_end) + wr_mas->end_piv = wr_mas->pivots[wr_mas->offset_end]; + else wr_mas->end_piv = wr_mas->mas->max; }
@@ -4423,7 +4425,6 @@ static inline void *mas_wr_store_entry(s }
/* At this point, we are at the leaf node that needs to be altered. */ - wr_mas->end_piv = wr_mas->r_max; mas_wr_end_piv(wr_mas);
if (!wr_mas->entry) _
Patches currently in -mm which might be from zhangpeng.00@bytedance.com are
maple_tree-make-maple-state-reusable-after-mas_empty_area.patch maple_tree-fix-potential-out-of-bounds-access-in-mas_wr_end_piv.patch