The patch titled
Subject: maple_tree: clean up after bulk allocation failure in mas_alloc_nodes()
has been added to the -mm tree. Its filename is
maple-tree-add-new-data-structure-fix.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/maple-tree-add-new-data-structure-fix.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/maple-tree-add-new-data-structure-fix.patch
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------------------------------------------------------
From: Liam Howlett <liam.howlett@xxxxxxxxxx>
Subject: maple_tree: clean up after bulk allocation failure in mas_alloc_nodes()
Link: https://lkml.kernel.org/r/20220419155055.qf52xpcftqb3r5nj@revolver
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/maple_tree.c | 22 ++++++++++++++--------
1 file changed, 14 insertions(+), 8 deletions(-)
--- a/lib/maple_tree.c~maple-tree-add-new-data-structure-fix
+++ a/lib/maple_tree.c
@@ -1206,6 +1206,8 @@ static inline void mas_alloc_nodes(struc
unsigned long success = allocated;
unsigned int requested = mas_alloc_req(mas);
unsigned int count;
+ void **slots = NULL;
+ unsigned int max_req = 0;
if (!requested)
return;
@@ -1214,7 +1216,7 @@ static inline void mas_alloc_nodes(struc
if (!allocated || mas->alloc->node_count == MAPLE_ALLOC_SLOTS - 1) {
node = (struct maple_alloc *)mt_alloc_one(gfp);
if (!node)
- goto nomem;
+ goto nomem_one;
if (allocated)
node->slot[0] = mas->alloc;
@@ -1226,20 +1228,20 @@ static inline void mas_alloc_nodes(struc
node = mas->alloc;
while (requested) {
- void **slots = (void **)&node->slot;
- unsigned int max_req = MAPLE_NODE_SLOTS - 1;
-
+ max_req = MAPLE_NODE_SLOTS - 1;
if (node->slot[0]) {
unsigned int offset = node->node_count + 1;
slots = (void **)&node->slot[offset];
max_req -= offset;
+ } else {
+ slots = (void **)&node->slot;
}
- count = mt_alloc_bulk(gfp, min(requested, max_req),
- slots);
+ max_req = min(requested, max_req);
+ count = mt_alloc_bulk(gfp, max_req, slots);
if (!count)
- goto nomem;
+ goto nomem_bulk;
node->node_count += count;
/* zero indexed. */
@@ -1253,7 +1255,11 @@ static inline void mas_alloc_nodes(struc
}
mas->alloc->total = success;
return;
-nomem:
+
+nomem_bulk:
+ /* Clean up potential freed allocations on bulk failure */
+ memset(slots, 0, max_req * sizeof(unsigned long));
+nomem_one:
mas_set_alloc_req(mas, requested);
if (mas->alloc && !(((unsigned long)mas->alloc & 0x1)))
mas->alloc->total = success;
_
Patches currently in -mm which might be from liam.howlett@xxxxxxxxxx are
radix-tree-test-suite-add-lockdep_is_held-to-header.patch
mips-rename-mt_init-to-mips_mt_init.patch
maple-tree-add-new-data-structure-fix.patch
lib-test_maple_tree-add-testing-for-maple-tree.patch
mmap-change-zeroing-of-maple-tree-in-__vma_adjust.patch
riscv-use-vma-iterator-for-vdso.patch
mm-mmapc-pass-in-mapping-to-__vma_link_file.patch
mglru-vs-maple-tree-fix.patch
