Hello Namjae Jeon,
This is a semi-automatic email about new static checker warnings.
The patch e43bb4e612b4: "ext4: decrement free clusters/inodes
counters when block group declared bad" from Jun 26, 2014, leads to
the following Smatch complaint:
fs/ext4/ialloc.c:343 ext4_free_inode()
error: we previously assumed 'gdp' could be null (see line 300)
fs/ext4/ialloc.c
299 gdp = ext4_get_group_desc(sb, block_group, &bh2);
300 if (gdp) {
^^^
Check for NULL.
301 BUFFER_TRACE(bh2, "get_write_access");
302 fatal = ext4_journal_get_write_access(handle, bh2);
303 }
304 ext4_lock_group(sb, block_group);
305 cleared = ext4_test_and_clear_bit(bit, bitmap_bh->b_data);
306 if (fatal || !cleared) {
307 ext4_unlock_group(sb, block_group);
308 goto out;
309 }
310
311 count = ext4_free_inodes_count(sb, gdp) + 1;
312 ext4_free_inodes_set(sb, gdp, count);
313 if (is_directory) {
314 count = ext4_used_dirs_count(sb, gdp) - 1;
315 ext4_used_dirs_set(sb, gdp, count);
316 percpu_counter_dec(&sbi->s_dirs_counter);
317 }
318 ext4_inode_bitmap_csum_set(sb, block_group, gdp, bitmap_bh,
319 EXT4_INODES_PER_GROUP(sb) / 8);
320 ext4_group_desc_csum_set(sb, block_group, gdp);
321 ext4_unlock_group(sb, block_group);
322
323 percpu_counter_inc(&sbi->s_freeinodes_counter);
324 if (sbi->s_log_groups_per_flex) {
325 ext4_group_t f = ext4_flex_group(sbi, block_group);
326
327 atomic_inc(&sbi->s_flex_groups[f].free_inodes);
328 if (is_directory)
329 atomic_dec(&sbi->s_flex_groups[f].used_dirs);
330 }
331 BUFFER_TRACE(bh2, "call ext4_handle_dirty_metadata");
332 fatal = ext4_handle_dirty_metadata(handle, NULL, bh2);
333 out:
334 if (cleared) {
335 BUFFER_TRACE(bitmap_bh, "call ext4_handle_dirty_metadata");
336 err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
337 if (!fatal)
338 fatal = err;
339 } else {
340 ext4_error(sb, "bit already cleared for inode %lu", ino);
341 if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
342 int count;
343 count = ext4_free_inodes_count(sb, gdp);
^^^
Patch adds new unchecked dereference inside the function call.
344 percpu_counter_sub(&sbi->s_freeinodes_counter,
345 count);
regards,
dan carpenter
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
