diff options
| author | Liu Shixin <[email protected]> | 2025-01-23 02:10:29 +0000 |
|---|---|---|
| committer | Andrew Morton <[email protected]> | 2025-01-26 04:42:30 +0000 |
| commit | d1366e74342e75555af2648a2964deb2d5c92200 (patch) | |
| tree | 4f61c69609b06ec356bbdadca947855d198942fe /mm/compaction.c | |
| parent | s390/mm: add missing ctor/dtor on page table upgrade (diff) | |
| download | kernel-d1366e74342e75555af2648a2964deb2d5c92200.tar.gz kernel-d1366e74342e75555af2648a2964deb2d5c92200.zip | |
mm/compaction: fix UBSAN shift-out-of-bounds warning
syzkaller reported a UBSAN shift-out-of-bounds warning of (1UL << order)
in isolate_freepages_block(). The bogus compound_order can be any value
because it is union with flags. Add back the MAX_PAGE_ORDER check to fix
the warning.
Link: https://lkml.kernel.org/r/[email protected]
Fixes: 3da0272a4c7d ("mm/compaction: correctly return failure with bogus compound_order in strict mode")
Signed-off-by: Liu Shixin <[email protected]>
Reviewed-by: Kemeng Shi <[email protected]>
Acked-by: David Hildenbrand <[email protected]>
Reviewed-by: Oscar Salvador <[email protected]>
Cc: Baolin Wang <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Kemeng Shi <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Nanyong Sun <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Diffstat (limited to 'mm/compaction.c')
| -rw-r--r-- | mm/compaction.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index 07bd22789f07..0f49f060d251 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -631,7 +631,8 @@ static unsigned long isolate_freepages_block(struct compact_control *cc, if (PageCompound(page)) { const unsigned int order = compound_order(page); - if (blockpfn + (1UL << order) <= end_pfn) { + if ((order <= MAX_PAGE_ORDER) && + (blockpfn + (1UL << order) <= end_pfn)) { blockpfn += (1UL << order) - 1; page += (1UL << order) - 1; nr_scanned += (1UL << order) - 1; |