| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <aRBVIcoLcBmQzwXU@rli9-mobl>
Date: Sun, 9 Nov 2025 16:47:29 +0800
From: Philip Li <philip.li@...el.com>
To: kernel test robot <lkp@...el.com>
CC: Filipe Manana <fdmanana@...e.com>, <oe-kbuild-all@...ts.linux.dev>,
<linux-kernel@...r.kernel.org>, David Sterba <dsterba@...e.com>
Subject: Re: fs/btrfs/tree-log.c:2649:32: warning: 'inode_item' may be used
uninitialized
On Sun, Nov 09, 2025 at 03:48:21AM +0800, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 0d7bee10beeb59b1133bf5a4749b17a4ef3bbb01
> commit: 2ac70946621ff3d90eb84d2e3b74563f4154f24c btrfs: add current log leaf, key and slot to struct walk_control
> date: 7 weeks ago
> config: um-randconfig-001-20251109 (https://download.01.org/0day-ci/archive/20251109/202511090321.X08Rh6eK-lkp@intel.com/config)
> compiler: gcc-13 (Debian 13.3.0-16) 13.3.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251109/202511090321.X08Rh6eK-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@...el.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202511090321.X08Rh6eK-lkp@intel.com/
>
> Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
> http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
>
> All warnings (new ones prefixed by >>):
Kindly ignore this report, it should be a false positive, sorry about this.
>
> fs/btrfs/tree-log.c: In function 'replay_one_buffer':
> >> fs/btrfs/tree-log.c:2649:32: warning: 'inode_item' may be used uninitialized [-Wmaybe-uninitialized]
> 2649 | mode = btrfs_inode_mode(eb, inode_item);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> fs/btrfs/tree-log.c:2607:42: note: 'inode_item' was declared here
> 2607 | struct btrfs_inode_item *inode_item;
> | ^~~~~~~~~~
>
>
> vim +/inode_item +2649 fs/btrfs/tree-log.c
>
> e02119d5a7b439 Chris Mason 2008-09-05 2563
> e02119d5a7b439 Chris Mason 2008-09-05 2564 /*
> e02119d5a7b439 Chris Mason 2008-09-05 2565 * the process_func used to replay items from the log tree. This
> e02119d5a7b439 Chris Mason 2008-09-05 2566 * gets called in two different stages. The first stage just looks
> e02119d5a7b439 Chris Mason 2008-09-05 2567 * for inodes and makes sure they are all copied into the subvolume.
> e02119d5a7b439 Chris Mason 2008-09-05 2568 *
> e02119d5a7b439 Chris Mason 2008-09-05 2569 * The second stage copies all the other item types from the log into
> e02119d5a7b439 Chris Mason 2008-09-05 2570 * the subvolume. The two stage approach is slower, but gets rid of
> e02119d5a7b439 Chris Mason 2008-09-05 2571 * lots of complexity around inodes referencing other inodes that exist
> e02119d5a7b439 Chris Mason 2008-09-05 2572 * only in the log (references come from either directory items or inode
> e02119d5a7b439 Chris Mason 2008-09-05 2573 * back refs).
> e02119d5a7b439 Chris Mason 2008-09-05 2574 */
> efa44fc4fde3eb Filipe Manana 2025-08-26 2575 static int replay_one_buffer(struct extent_buffer *eb,
> 581c1760415c48 Qu Wenruo 2018-03-29 2576 struct walk_control *wc, u64 gen, int level)
> e02119d5a7b439 Chris Mason 2008-09-05 2577 {
> e02119d5a7b439 Chris Mason 2008-09-05 2578 int nritems;
> 789d6a3a876e32 Qu Wenruo 2022-09-14 2579 struct btrfs_tree_parent_check check = {
> 789d6a3a876e32 Qu Wenruo 2022-09-14 2580 .transid = gen,
> 789d6a3a876e32 Qu Wenruo 2022-09-14 2581 .level = level
> 789d6a3a876e32 Qu Wenruo 2022-09-14 2582 };
> e02119d5a7b439 Chris Mason 2008-09-05 2583 struct btrfs_path *path;
> 2c123db1f0e1fb Filipe Manana 2025-08-26 2584 struct btrfs_root *root = wc->root;
> 425652cf102838 Filipe Manana 2025-07-16 2585 struct btrfs_trans_handle *trans = wc->trans;
> e02119d5a7b439 Chris Mason 2008-09-05 2586 int ret;
> e02119d5a7b439 Chris Mason 2008-09-05 2587
> 6cb7f0b8c9b0d6 Filipe Manana 2025-08-28 2588 if (level != 0)
> 6cb7f0b8c9b0d6 Filipe Manana 2025-08-28 2589 return 0;
> 6cb7f0b8c9b0d6 Filipe Manana 2025-08-28 2590
> 789d6a3a876e32 Qu Wenruo 2022-09-14 2591 ret = btrfs_read_extent_buffer(eb, &check);
> 912c257c88cd8c Filipe Manana 2025-07-18 2592 if (ret) {
> 912c257c88cd8c Filipe Manana 2025-07-18 2593 btrfs_abort_transaction(trans, ret);
> 018642a1f19788 Tsutomu Itoh 2012-05-29 2594 return ret;
> 912c257c88cd8c Filipe Manana 2025-07-18 2595 }
> e02119d5a7b439 Chris Mason 2008-09-05 2596
> e02119d5a7b439 Chris Mason 2008-09-05 2597 path = btrfs_alloc_path();
> 912c257c88cd8c Filipe Manana 2025-07-18 2598 if (!path) {
> 912c257c88cd8c Filipe Manana 2025-07-18 2599 btrfs_abort_transaction(trans, -ENOMEM);
> 1e5063d093b5f0 Mark Fasheh 2011-07-12 2600 return -ENOMEM;
> 912c257c88cd8c Filipe Manana 2025-07-18 2601 }
> e02119d5a7b439 Chris Mason 2008-09-05 2602
> 2ac70946621ff3 Filipe Manana 2025-09-01 2603 wc->log_leaf = eb;
> 2ac70946621ff3 Filipe Manana 2025-09-01 2604
> e02119d5a7b439 Chris Mason 2008-09-05 2605 nritems = btrfs_header_nritems(eb);
> 2ac70946621ff3 Filipe Manana 2025-09-01 2606 for (wc->log_slot = 0; wc->log_slot < nritems; wc->log_slot++) {
> e02119d5a7b439 Chris Mason 2008-09-05 2607 struct btrfs_inode_item *inode_item;
> e02119d5a7b439 Chris Mason 2008-09-05 2608
> 2ac70946621ff3 Filipe Manana 2025-09-01 2609 btrfs_item_key_to_cpu(eb, &wc->log_key, wc->log_slot);
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2610
> 2ac70946621ff3 Filipe Manana 2025-09-01 2611 if (wc->log_key.type == BTRFS_INODE_ITEM_KEY) {
> 2ac70946621ff3 Filipe Manana 2025-09-01 2612 inode_item = btrfs_item_ptr(eb, wc->log_slot,
> 2ac70946621ff3 Filipe Manana 2025-09-01 2613 struct btrfs_inode_item);
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2614 /*
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2615 * An inode with no links is either:
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2616 *
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2617 * 1) A tmpfile (O_TMPFILE) that got fsync'ed and never
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2618 * got linked before the fsync, skip it, as replaying
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2619 * it is pointless since it would be deleted later.
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2620 * We skip logging tmpfiles, but it's always possible
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2621 * we are replaying a log created with a kernel that
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2622 * used to log tmpfiles;
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2623 *
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2624 * 2) A non-tmpfile which got its last link deleted
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2625 * while holding an open fd on it and later got
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2626 * fsynced through that fd. We always log the
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2627 * parent inodes when inode->last_unlink_trans is
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2628 * set to the current transaction, so ignore all the
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2629 * inode items for this inode. We will delete the
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2630 * inode when processing the parent directory with
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2631 * replay_dir_deletes().
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2632 */
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2633 if (btrfs_inode_nlink(eb, inode_item) == 0) {
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2634 wc->ignore_cur_inode = true;
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2635 continue;
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2636 } else {
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2637 wc->ignore_cur_inode = false;
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2638 }
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2639 }
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2640
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2641 /* Inode keys are done during the first stage. */
> 2ac70946621ff3 Filipe Manana 2025-09-01 2642 if (wc->log_key.type == BTRFS_INODE_ITEM_KEY &&
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2643 wc->stage == LOG_WALK_REPLAY_INODES) {
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2644 u32 mode;
> 0a32e4f0025a74 Filipe Manana 2025-07-30 2645
> 2ac70946621ff3 Filipe Manana 2025-09-01 2646 ret = replay_xattr_deletes(wc, path);
> 4f764e5153616f Filipe Manana 2015-02-23 2647 if (ret)
> 4f764e5153616f Filipe Manana 2015-02-23 2648 break;
> e02119d5a7b439 Chris Mason 2008-09-05 @2649 mode = btrfs_inode_mode(eb, inode_item);
> e02119d5a7b439 Chris Mason 2008-09-05 2650 if (S_ISDIR(mode)) {
> 2ac70946621ff3 Filipe Manana 2025-09-01 2651 ret = replay_dir_deletes(wc, path, wc->log_key.objectid, false);
> b50c6e250ef913 Josef Bacik 2013-04-25 2652 if (ret)
> b50c6e250ef913 Josef Bacik 2013-04-25 2653 break;
> e02119d5a7b439 Chris Mason 2008-09-05 2654 }
> 2ac70946621ff3 Filipe Manana 2025-09-01 2655 ret = overwrite_item(wc, path);
> b50c6e250ef913 Josef Bacik 2013-04-25 2656 if (ret)
> b50c6e250ef913 Josef Bacik 2013-04-25 2657 break;
> e02119d5a7b439 Chris Mason 2008-09-05 2658
> 471d557afed155 Filipe Manana 2018-04-05 2659 /*
> 471d557afed155 Filipe Manana 2018-04-05 2660 * Before replaying extents, truncate the inode to its
> 471d557afed155 Filipe Manana 2018-04-05 2661 * size. We need to do it now and not after log replay
> 471d557afed155 Filipe Manana 2018-04-05 2662 * because before an fsync we can have prealloc extents
> 471d557afed155 Filipe Manana 2018-04-05 2663 * added beyond the inode's i_size. If we did it after,
> 471d557afed155 Filipe Manana 2018-04-05 2664 * through orphan cleanup for example, we would drop
> 471d557afed155 Filipe Manana 2018-04-05 2665 * those prealloc extents just after replaying them.
> e02119d5a7b439 Chris Mason 2008-09-05 2666 */
> e02119d5a7b439 Chris Mason 2008-09-05 2667 if (S_ISREG(mode)) {
> 5893dfb98f2578 Filipe Manana 2020-11-04 2668 struct btrfs_drop_extents_args drop_args = { 0 };
> b4c50cbb01a1b6 Filipe Manana 2025-03-06 2669 struct btrfs_inode *inode;
> 471d557afed155 Filipe Manana 2018-04-05 2670 u64 from;
> 471d557afed155 Filipe Manana 2018-04-05 2671
> 2ac70946621ff3 Filipe Manana 2025-09-01 2672 inode = btrfs_iget_logging(wc->log_key.objectid, root);
> 5f61b961599acb Filipe Manana 2025-06-18 2673 if (IS_ERR(inode)) {
> 5f61b961599acb Filipe Manana 2025-06-18 2674 ret = PTR_ERR(inode);
> 912c257c88cd8c Filipe Manana 2025-07-18 2675 btrfs_abort_transaction(trans, ret);
> 471d557afed155 Filipe Manana 2018-04-05 2676 break;
> 471d557afed155 Filipe Manana 2018-04-05 2677 }
> b4c50cbb01a1b6 Filipe Manana 2025-03-06 2678 from = ALIGN(i_size_read(&inode->vfs_inode),
> 471d557afed155 Filipe Manana 2018-04-05 2679 root->fs_info->sectorsize);
> 5893dfb98f2578 Filipe Manana 2020-11-04 2680 drop_args.start = from;
> 5893dfb98f2578 Filipe Manana 2020-11-04 2681 drop_args.end = (u64)-1;
> 5893dfb98f2578 Filipe Manana 2020-11-04 2682 drop_args.drop_cache = true;
> 425652cf102838 Filipe Manana 2025-07-16 2683 ret = btrfs_drop_extents(trans, root, inode, &drop_args);
> 912c257c88cd8c Filipe Manana 2025-07-18 2684 if (ret) {
> 912c257c88cd8c Filipe Manana 2025-07-18 2685 btrfs_abort_transaction(trans, ret);
> 912c257c88cd8c Filipe Manana 2025-07-18 2686 } else {
> b4c50cbb01a1b6 Filipe Manana 2025-03-06 2687 inode_sub_bytes(&inode->vfs_inode,
> 2766ff61762c3f Filipe Manana 2020-11-04 2688 drop_args.bytes_found);
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2689 /* Update the inode's nbytes. */
> 425652cf102838 Filipe Manana 2025-07-16 2690 ret = btrfs_update_inode(trans, inode);
> 912c257c88cd8c Filipe Manana 2025-07-18 2691 if (ret)
> 912c257c88cd8c Filipe Manana 2025-07-18 2692 btrfs_abort_transaction(trans, ret);
> 471d557afed155 Filipe Manana 2018-04-05 2693 }
> b4c50cbb01a1b6 Filipe Manana 2025-03-06 2694 iput(&inode->vfs_inode);
> b50c6e250ef913 Josef Bacik 2013-04-25 2695 if (ret)
> b50c6e250ef913 Josef Bacik 2013-04-25 2696 break;
> e02119d5a7b439 Chris Mason 2008-09-05 2697 }
> c71bf099abddf3 Yan, Zheng 2009-11-12 2698
> 2ac70946621ff3 Filipe Manana 2025-09-01 2699 ret = link_to_fixup_dir(wc, path, wc->log_key.objectid);
> b50c6e250ef913 Josef Bacik 2013-04-25 2700 if (ret)
> b50c6e250ef913 Josef Bacik 2013-04-25 2701 break;
> e02119d5a7b439 Chris Mason 2008-09-05 2702 }
> dd8e721773fdab Josef Bacik 2013-09-11 2703
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2704 if (wc->ignore_cur_inode)
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2705 continue;
> f2d72f42d5fa3b Filipe Manana 2018-10-08 2706
> 2ac70946621ff3 Filipe Manana 2025-09-01 2707 if (wc->log_key.type == BTRFS_DIR_INDEX_KEY &&
> dd8e721773fdab Josef Bacik 2013-09-11 2708 wc->stage == LOG_WALK_REPLAY_DIR_INDEX) {
> 2ac70946621ff3 Filipe Manana 2025-09-01 2709 ret = replay_one_dir_item(wc, path);
> dd8e721773fdab Josef Bacik 2013-09-11 2710 if (ret)
> dd8e721773fdab Josef Bacik 2013-09-11 2711 break;
> dd8e721773fdab Josef Bacik 2013-09-11 2712 }
> dd8e721773fdab Josef Bacik 2013-09-11 2713
> e02119d5a7b439 Chris Mason 2008-09-05 2714 if (wc->stage < LOG_WALK_REPLAY_ALL)
> e02119d5a7b439 Chris Mason 2008-09-05 2715 continue;
> e02119d5a7b439 Chris Mason 2008-09-05 2716
> e02119d5a7b439 Chris Mason 2008-09-05 2717 /* these keys are simply copied */
> 2ac70946621ff3 Filipe Manana 2025-09-01 2718 if (wc->log_key.type == BTRFS_XATTR_ITEM_KEY) {
> 2ac70946621ff3 Filipe Manana 2025-09-01 2719 ret = overwrite_item(wc, path);
> b50c6e250ef913 Josef Bacik 2013-04-25 2720 if (ret)
> b50c6e250ef913 Josef Bacik 2013-04-25 2721 break;
> 2ac70946621ff3 Filipe Manana 2025-09-01 2722 } else if (wc->log_key.type == BTRFS_INODE_REF_KEY ||
> 2ac70946621ff3 Filipe Manana 2025-09-01 2723 wc->log_key.type == BTRFS_INODE_EXTREF_KEY) {
> 2ac70946621ff3 Filipe Manana 2025-09-01 2724 ret = add_inode_ref(wc, path);
> 7ebf381a69421a Filipe Manana 2025-07-11 2725 if (ret)
> b50c6e250ef913 Josef Bacik 2013-04-25 2726 break;
> 2ac70946621ff3 Filipe Manana 2025-09-01 2727 } else if (wc->log_key.type == BTRFS_EXTENT_DATA_KEY) {
> 2ac70946621ff3 Filipe Manana 2025-09-01 2728 ret = replay_one_extent(wc, path);
> b50c6e250ef913 Josef Bacik 2013-04-25 2729 if (ret)
> b50c6e250ef913 Josef Bacik 2013-04-25 2730 break;
> e02119d5a7b439 Chris Mason 2008-09-05 2731 }
> 339d035424849c Filipe Manana 2021-10-25 2732 /*
> 339d035424849c Filipe Manana 2021-10-25 2733 * We don't log BTRFS_DIR_ITEM_KEY keys anymore, only the
> 339d035424849c Filipe Manana 2021-10-25 2734 * BTRFS_DIR_INDEX_KEY items which we use to derive the
> 339d035424849c Filipe Manana 2021-10-25 2735 * BTRFS_DIR_ITEM_KEY items. If we are replaying a log from an
> 339d035424849c Filipe Manana 2021-10-25 2736 * older kernel with such keys, ignore them.
> 339d035424849c Filipe Manana 2021-10-25 2737 */
> e02119d5a7b439 Chris Mason 2008-09-05 2738 }
> e02119d5a7b439 Chris Mason 2008-09-05 2739 btrfs_free_path(path);
> b50c6e250ef913 Josef Bacik 2013-04-25 2740 return ret;
> e02119d5a7b439 Chris Mason 2008-09-05 2741 }
> e02119d5a7b439 Chris Mason 2008-09-05 2742
>
> :::::: The code at line 2649 was first introduced by commit
> :::::: e02119d5a7b4396c5a872582fddc8bd6d305a70a Btrfs: Add a write ahead tree log to optimize synchronous operations
>
> :::::: TO: Chris Mason <chris.mason@...cle.com>
> :::::: CC: Chris Mason <chris.mason@...cle.com>
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
>
Powered by blists - more mailing lists