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| author | Victor Stinner <vstinner@python.org> | 2024-04-16 20:34:12 (GMT) |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2024-04-16 20:34:12 (GMT) |
| commit | 3fe03ccea61121b05e933013f76aa02f690014c1 (patch) | |
| tree | 8da922b3d5a618c6324c6ad6d9bf613d639a9d52 | |
| parent | e05d202ebf0904cf0a980fde76f4a38bb8dc7c3b (diff) | |
| download | cpython-3fe03ccea61121b05e933013f76aa02f690014c1.zip cpython-3fe03ccea61121b05e933013f76aa02f690014c1.tar.gz cpython-3fe03ccea61121b05e933013f76aa02f690014c1.tar.bz2 | |
gh-117755: Fix mimalloc for huge allocation on s390x (#117809)
Fix mimalloc allocator for huge memory allocation (around
8,589,934,592 GiB) on s390x.
Abort allocation early in mimalloc if the number of slices doesn't
fit into uint32_t, to prevent a integer overflow (cast 64-bit
size_t to uint32_t).
| -rw-r--r-- | Misc/NEWS.d/next/Core and Builtins/2024-04-12-12-28-49.gh-issue-117755.6ct8kU.rst | 2 | ||||
| -rw-r--r-- | Objects/mimalloc/segment.c | 6 |
2 files changed, 8 insertions, 0 deletions
diff --git a/Misc/NEWS.d/next/Core and Builtins/2024-04-12-12-28-49.gh-issue-117755.6ct8kU.rst b/Misc/NEWS.d/next/Core and Builtins/2024-04-12-12-28-49.gh-issue-117755.6ct8kU.rst new file mode 100644 index 0000000..a65ec43 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2024-04-12-12-28-49.gh-issue-117755.6ct8kU.rst @@ -0,0 +1,2 @@ +Fix mimalloc allocator for huge memory allocation (around 8,589,934,592 GiB) on +s390x. Patch by Victor Stinner. diff --git a/Objects/mimalloc/segment.c b/Objects/mimalloc/segment.c index 08b1564..0b4d3ab 100644 --- a/Objects/mimalloc/segment.c +++ b/Objects/mimalloc/segment.c @@ -814,6 +814,9 @@ static mi_segment_t* mi_segment_os_alloc( size_t required, size_t page_alignment const size_t extra = align_offset - info_size; // recalculate due to potential guard pages *psegment_slices = mi_segment_calculate_slices(required + extra, ppre_size, pinfo_slices); + + // mi_page_t.slice_count type is uint32_t + if (*psegment_slices > (size_t)UINT32_MAX) return NULL; } const size_t segment_size = (*psegment_slices) * MI_SEGMENT_SLICE_SIZE; @@ -865,6 +868,9 @@ static mi_segment_t* mi_segment_alloc(size_t required, size_t page_alignment, mi size_t pre_size; size_t segment_slices = mi_segment_calculate_slices(required, &pre_size, &info_slices); + // mi_page_t.slice_count type is uint32_t + if (segment_slices > (size_t)UINT32_MAX) return NULL; + // Commit eagerly only if not the first N lazy segments (to reduce impact of many threads that allocate just a little) const bool eager_delay = (// !_mi_os_has_overcommit() && // never delay on overcommit systems _mi_current_thread_count() > 1 && // do not delay for the first N threads |