From: Hongfu Li <[email protected]> In mremap_dontunmap_partial_mapping_overwrite(), mremap() stores its returned remapped address into remapped_mapping, while the BUG_ON incorrectly checks dest_mapping instead.
If mremap() fails, dest_mapping still holds a valid pointer obtained from the prior mmap() call, making this BUG_ON never trigger at all. Correct the check to validate the actual mremap() return value stored in remapped_mapping. Signed-off-by: Hongfu Li <[email protected]> --- tools/testing/selftests/mm/mremap_dontunmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/mremap_dontunmap.c b/tools/testing/selftests/mm/mremap_dontunmap.c index a4f75d836733..96ba537facf7 100644 --- a/tools/testing/selftests/mm/mremap_dontunmap.c +++ b/tools/testing/selftests/mm/mremap_dontunmap.c @@ -313,7 +313,7 @@ static void mremap_dontunmap_partial_mapping_overwrite(void) mremap(source_mapping, 5 * page_size, 5 * page_size, MREMAP_DONTUNMAP | MREMAP_MAYMOVE | MREMAP_FIXED, dest_mapping); - BUG_ON(dest_mapping == MAP_FAILED, "mremap"); + BUG_ON(remapped_mapping == MAP_FAILED, "mremap"); BUG_ON(dest_mapping != remapped_mapping, "expected to remap to dest_mapping"); BUG_ON(check_region_contains_byte(source_mapping, 5 * page_size, 0) != -- 2.54.0
