Check the return value of md_bitmap_get_counter() in case it returns NULL pointer, which will result in a null pointer dereference. Signed-off-by: Li Zhong <floridsleeves@xxxxxxxxx> --- drivers/md/md-bitmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c index bf6dffadbe6f..06ab1098ff99 100644 --- a/drivers/md/md-bitmap.c +++ b/drivers/md/md-bitmap.c @@ -2195,7 +2195,7 @@ int md_bitmap_resize(struct bitmap *bitmap, sector_t blocks, if (set) { bmc_new = md_bitmap_get_counter(&bitmap->counts, block, &new_blocks, 1); - if (*bmc_new == 0) { + if (bmc_new && *bmc_new == 0) { /* need to set on-disk bits too. */ sector_t end = block + new_blocks; sector_t start = block >> chunkshift; -- 2.25.1