[kbuild-all] [chao-linux:simple_copy 2/5] block/blk-lib.c:221 blk_read_to_buf() error: uninitialized symbol 'bio'.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git simple_copy head: d6f32b90156624ae9dc06ef5873334a48e9b9806 commit: fcbd83ffa72af1eba12bcab1f34e0b956a563e02 [2/5] block: add simple copy support config: xtensa-randconfig-m031-20210209 (attached as .config) compiler: xtensa-linux-gcc (GCC) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: block/blk-lib.c:221 blk_read_to_buf() error: uninitialized symbol 'bio'. block/blk-lib.c:352 blkdev_issue_copy() warn: ignoring unreachable code. vim +/bio +221 block/blk-lib.c fcbd83ffa72af1e SelvaKumar S 2021-02-08 180 int blk_read_to_buf(struct block_device *bdev, struct blk_copy_payload *payload, fcbd83ffa72af1e SelvaKumar S 2021-02-08 181 gfp_t gfp_mask, void **buf_p) fcbd83ffa72af1e SelvaKumar S 2021-02-08 182 { fcbd83ffa72af1e SelvaKumar S 2021-02-08 183 struct request_queue *q = bdev_get_queue(bdev); fcbd83ffa72af1e SelvaKumar S 2021-02-08 184 struct bio *bio, *parent = NULL; fcbd83ffa72af1e SelvaKumar S 2021-02-08 185 void *buf = NULL; fcbd83ffa72af1e SelvaKumar S 2021-02-08 186 bool is_vmalloc; fcbd83ffa72af1e SelvaKumar S 2021-02-08 187 int i, nr_srcs, copy_len, ret, cur_size, t_len = 0; fcbd83ffa72af1e SelvaKumar S 2021-02-08 188 fcbd83ffa72af1e SelvaKumar S 2021-02-08 189 nr_srcs = payload->copy_range; fcbd83ffa72af1e SelvaKumar S 2021-02-08 190 copy_len = payload->copy_size << SECTOR_SHIFT; fcbd83ffa72af1e SelvaKumar S 2021-02-08 191 fcbd83ffa72af1e SelvaKumar S 2021-02-08 192 buf = kvmalloc(copy_len, gfp_mask); fcbd83ffa72af1e SelvaKumar S 2021-02-08 193 if (!buf) fcbd83ffa72af1e SelvaKumar S 2021-02-08 194 return -ENOMEM; fcbd83ffa72af1e SelvaKumar S 2021-02-08 195 is_vmalloc = is_vmalloc_addr(buf); fcbd83ffa72af1e SelvaKumar S 2021-02-08 196 fcbd83ffa72af1e SelvaKumar S 2021-02-08 197 for (i = 0; i < nr_srcs; i++) { Smatch is complaining that if "nr_secs" is zero then this leads to an uninitialized variable warning. As a human reviewer I would worry that payload->copy_range can be controlled by the user, but I don't have an easy way to check. fcbd83ffa72af1e SelvaKumar S 2021-02-08 198 cur_size = payload->range[i].len << SECTOR_SHIFT; fcbd83ffa72af1e SelvaKumar S 2021-02-08 199 fcbd83ffa72af1e SelvaKumar S 2021-02-08 200 bio = bio_map_kern(q, buf + t_len, cur_size, gfp_mask); fcbd83ffa72af1e SelvaKumar S 2021-02-08 201 if (IS_ERR(bio)) { fcbd83ffa72af1e SelvaKumar S 2021-02-08 202 ret = PTR_ERR(bio); fcbd83ffa72af1e SelvaKumar S 2021-02-08 203 goto out; fcbd83ffa72af1e SelvaKumar S 2021-02-08 204 } fcbd83ffa72af1e SelvaKumar S 2021-02-08 205 fcbd83ffa72af1e SelvaKumar S 2021-02-08 206 bio->bi_iter.bi_sector = payload->range[i].src; fcbd83ffa72af1e SelvaKumar S 2021-02-08 207 bio->bi_opf = REQ_OP_READ; fcbd83ffa72af1e SelvaKumar S 2021-02-08 208 bio_set_dev(bio, bdev); fcbd83ffa72af1e SelvaKumar S 2021-02-08 209 bio->bi_end_io = NULL; fcbd83ffa72af1e SelvaKumar S 2021-02-08 210 bio->bi_private = NULL; fcbd83ffa72af1e SelvaKumar S 2021-02-08 211 fcbd83ffa72af1e SelvaKumar S 2021-02-08 212 if (parent) { fcbd83ffa72af1e SelvaKumar S 2021-02-08 213 bio_chain(parent, bio); fcbd83ffa72af1e SelvaKumar S 2021-02-08 214 submit_bio(parent); fcbd83ffa72af1e SelvaKumar S 2021-02-08 215 } fcbd83ffa72af1e SelvaKumar S 2021-02-08 216 fcbd83ffa72af1e SelvaKumar S 2021-02-08 217 parent = bio; fcbd83ffa72af1e SelvaKumar S 2021-02-08 218 t_len += cur_size; fcbd83ffa72af1e SelvaKumar S 2021-02-08 219 } fcbd83ffa72af1e SelvaKumar S 2021-02-08 220 fcbd83ffa72af1e SelvaKumar S 2021-02-08 @221 ret = submit_bio_wait(bio); ^^^ fcbd83ffa72af1e SelvaKumar S 2021-02-08 222 bio_put(bio); fcbd83ffa72af1e SelvaKumar S 2021-02-08 223 if (is_vmalloc) fcbd83ffa72af1e SelvaKumar S 2021-02-08 224 invalidate_kernel_vmap_range(buf, copy_len); fcbd83ffa72af1e SelvaKumar S 2021-02-08 225 if (ret) fcbd83ffa72af1e SelvaKumar S 2021-02-08 226 goto out; fcbd83ffa72af1e SelvaKumar S 2021-02-08 227 fcbd83ffa72af1e SelvaKumar S 2021-02-08 228 *buf_p = buf; fcbd83ffa72af1e SelvaKumar S 2021-02-08 229 return 0; fcbd83ffa72af1e SelvaKumar S 2021-02-08 230 out: fcbd83ffa72af1e SelvaKumar S 2021-02-08 231 kvfree(buf); fcbd83ffa72af1e SelvaKumar S 2021-02-08 232 return ret; fcbd83ffa72af1e SelvaKumar S 2021-02-08 233 } [ snip ] fcbd83ffa72af1e SelvaKumar S 2021-02-08 335 int blkdev_issue_copy(struct block_device *bdev, int nr_srcs, fcbd83ffa72af1e SelvaKumar S 2021-02-08 336 struct range_entry *src_rlist, struct block_device *dest_bdev, fcbd83ffa72af1e SelvaKumar S 2021-02-08 337 sector_t dest, gfp_t gfp_mask) fcbd83ffa72af1e SelvaKumar S 2021-02-08 338 { fcbd83ffa72af1e SelvaKumar S 2021-02-08 339 struct request_queue *q = bdev_get_queue(bdev); fcbd83ffa72af1e SelvaKumar S 2021-02-08 340 struct blk_copy_payload *payload; fcbd83ffa72af1e SelvaKumar S 2021-02-08 341 sector_t bs_mask, dest_sect; fcbd83ffa72af1e SelvaKumar S 2021-02-08 342 void *buf = NULL; fcbd83ffa72af1e SelvaKumar S 2021-02-08 343 int ret; fcbd83ffa72af1e SelvaKumar S 2021-02-08 344 fcbd83ffa72af1e SelvaKumar S 2021-02-08 345 ret = blk_prepare_payload(bdev, nr_srcs, src_rlist, gfp_mask, &payload); fcbd83ffa72af1e SelvaKumar S 2021-02-08 346 if (ret) fcbd83ffa72af1e SelvaKumar S 2021-02-08 347 return ret; fcbd83ffa72af1e SelvaKumar S 2021-02-08 348 fcbd83ffa72af1e SelvaKumar S 2021-02-08 349 bs_mask = (bdev_logical_block_size(dest_bdev) >> 9) - 1; fcbd83ffa72af1e SelvaKumar S 2021-02-08 350 if (dest & bs_mask) { fcbd83ffa72af1e SelvaKumar S 2021-02-08 351 return -EINVAL; ^^^^^^^^^^^^^^^ fcbd83ffa72af1e SelvaKumar S 2021-02-08 @352 goto out; ^^^^^^^^ Memory leak of "payload". fcbd83ffa72af1e SelvaKumar S 2021-02-08 353 } fcbd83ffa72af1e SelvaKumar S 2021-02-08 354 dest_sect = dest >> SECTOR_SHIFT; fcbd83ffa72af1e SelvaKumar S 2021-02-08 355 fcbd83ffa72af1e SelvaKumar S 2021-02-08 356 if (bdev == dest_bdev && q->limits.copy_offload) { fcbd83ffa72af1e SelvaKumar S 2021-02-08 357 ret = blk_copy_offload(bdev, payload, dest_sect, gfp_mask); fcbd83ffa72af1e SelvaKumar S 2021-02-08 358 if (ret) fcbd83ffa72af1e SelvaKumar S 2021-02-08 359 goto out; fcbd83ffa72af1e SelvaKumar S 2021-02-08 360 } else { fcbd83ffa72af1e SelvaKumar S 2021-02-08 361 ret = blk_read_to_buf(bdev, payload, gfp_mask, &buf); fcbd83ffa72af1e SelvaKumar S 2021-02-08 362 if (ret) fcbd83ffa72af1e SelvaKumar S 2021-02-08 363 goto out; fcbd83ffa72af1e SelvaKumar S 2021-02-08 364 ret = blk_write_from_buf(dest_bdev, buf, dest_sect, fcbd83ffa72af1e SelvaKumar S 2021-02-08 365 payload->copy_size << SECTOR_SHIFT, gfp_mask); fcbd83ffa72af1e SelvaKumar S 2021-02-08 366 } fcbd83ffa72af1e SelvaKumar S 2021-02-08 367 fcbd83ffa72af1e SelvaKumar S 2021-02-08 368 if (buf) fcbd83ffa72af1e SelvaKumar S 2021-02-08 369 kvfree(buf); fcbd83ffa72af1e SelvaKumar S 2021-02-08 370 out: fcbd83ffa72af1e SelvaKumar S 2021-02-08 371 kvfree(payload); fcbd83ffa72af1e SelvaKumar S 2021-02-08 372 return ret; fcbd83ffa72af1e SelvaKumar S 2021-02-08 373 } --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org