kernel.git/fs/quota, branch linux-5.19.y

quota: Check next/prev free block number after reading from quota file

2022-10-24T07:56:44Z

commit 6c8ea8b8cd4722efd419f91ca46a2dc81b7d89a3 upstream. Following process: Init: v2_read_file_info: <3> dqi_free_blk 0 dqi_free_entry 5 dqi_blks 6 Step 1. chown bin f_a -> dquot_acquire -> v2_write_dquot: qtree_write_dquot do_insert_tree find_free_dqentry get_free_dqblk write_blk(info->dqi_blocks) // info->dqi_blocks = 6, failure. The content in physical block (corresponding to blk 6) is random. Step 2. chown root f_a -> dquot_transfer -> dqput_all -> dqput -> ext4_release_dquot -> v2_release_dquot -> qtree_delete_dquot: dquot_release remove_tree free_dqentry put_free_dqblk(6) info->dqi_free_blk = blk // info->dqi_free_blk = 6 Step 3. drop cache (buffer head for block 6 is released) Step 4. chown bin f_b -> dquot_acquire -> commit_dqblk -> v2_write_dquot: qtree_write_dquot do_insert_tree find_free_dqentry get_free_dqblk dh = (struct qt_disk_dqdbheader *)buf blk = info->dqi_free_blk // 6 ret = read_blk(info, blk, buf) // The content of buf is random info->dqi_free_blk = le32_to_cpu(dh->dqdh_next_free) // random blk Step 5. chown bin f_c -> notify_change -> ext4_setattr -> dquot_transfer: dquot = dqget -> acquire_dquot -> ext4_acquire_dquot -> dquot_acquire -> commit_dqblk -> v2_write_dquot -> dq_insert_tree: do_insert_tree find_free_dqentry get_free_dqblk blk = info->dqi_free_blk // If blk < 0 and blk is not an error code, it will be returned as dquot transfer_to[USRQUOTA] = dquot // A random negative value __dquot_transfer(transfer_to) dquot_add_inodes(transfer_to[cnt]) spin_lock(&dquot->dq_dqb_lock) // page fault , which will lead to kernel page fault: Quota error (device sda): qtree_write_dquot: Error -8000 occurred while creating quota BUG: unable to handle page fault for address: ffffffffffffe120 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page Oops: 0002 [#1] PREEMPT SMP CPU: 0 PID: 5974 Comm: chown Not tainted 6.0.0-rc1-00004 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:_raw_spin_lock+0x3a/0x90 Call Trace: dquot_add_inodes+0x28/0x270 __dquot_transfer+0x377/0x840 dquot_transfer+0xde/0x540 ext4_setattr+0x405/0x14d0 notify_change+0x68e/0x9f0 chown_common+0x300/0x430 __x64_sys_fchownat+0x29/0x40 In order to avoid accessing invalid quota memory address, this patch adds block number checking of next/prev free block read from quota file. Fetch a reproducer in [Link]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=216372 Fixes: 1da177e4c3f4152 ("Linux-2.6.12-rc2") CC: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220923134555.2623931-2-chengzhihao1@huawei.com Signed-off-by: Zhihao Cheng Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman

quota: Prevent memory allocation recursion while holding dq_lock

2022-06-06T08:08:10Z

As described in commit 02117b8ae9c0 ("f2fs: Set GF_NOFS in read_cache_page_gfp while doing f2fs_quota_read"), we must not enter filesystem reclaim while holding the dq_lock. Prevent this more generally by using memalloc_nofs_save() while holding the lock. Link: https://lore.kernel.org/r/20220605143815.2330891-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Jan Kara

quota: make dquot_quota_sync return errors from ->sync_fs

2022-01-30T16:59:47Z

Strangely, dquot_quota_sync ignores the return code from the ->sync_fs call, which means that quotacalls like Q_SYNC never see the error. This doesn't seem right, so fix that. Signed-off-by: Darrick J. Wong Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Acked-by: Christian Brauner

Merge tag 'fs_for_v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2021-11-06T23:40:48Z

Pull quota, isofs, and reiserfs updates from Jan Kara: "Fixes for handling of corrupted quota files, fix for handling of corrupted isofs filesystem, and a small cleanup for reiserfs" * tag 'fs_for_v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fs: reiserfs: remove useless new_opts in reiserfs_remount isofs: Fix out of bound access for corrupted isofs image quota: correct error number in free_dqentry() quota: check block number when reading the block in quota file

mm: don't include in

2021-10-18T12:17:01Z

blk-cgroup.h pulls in blkdev.h and thus pretty much all the block headers. Break this dependency chain by turning wbc_blkcg_css into a macro and dropping the blk-cgroup.h include. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20210920123328.1399408-2-hch@lst.de Signed-off-by: Jens Axboe

quota: correct error number in free_dqentry()

2021-10-11T08:57:04Z

Fix the error path in free_dqentry(), pass out the error number if the block to free is not correct. Fixes: 1ccd14b9c271 ("quota: Split off quota tree handling into a separate file") Link: https://lore.kernel.org/r/20211008093821.1001186-3-yi.zhang@huawei.com Signed-off-by: Zhang Yi Cc: stable@kernel.org Signed-off-by: Jan Kara

quota: check block number when reading the block in quota file

2021-10-11T08:55:47Z

The block number in the quota tree on disk should be smaller than the v2_disk_dqinfo.dqi_blocks. If the quota file was corrupted, we may be allocating an 'allocated' block and that would lead to a loop in a tree, which will probably trigger oops later. This patch adds a check for the block number in the quota tree to prevent such potential issue. Link: https://lore.kernel.org/r/20211008093821.1001186-2-yi.zhang@huawei.com Signed-off-by: Zhang Yi Cc: stable@kernel.org Signed-off-by: Jan Kara

quota: remove unnecessary oom message

2021-06-22T08:40:52Z

Fixes scripts/checkpatch.pl warning: WARNING: Possible unnecessary 'out of memory' message Remove it can help us save a bit of memory. After that, the static function getdqbuf() becomes unnecessary, get rid of it and instead call kmalloc() directly. Link: https://lore.kernel.org/r/20210618014720.1977-2-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei Signed-off-by: Jan Kara

quota: Change quotactl_path() systcall to an fd-based one

2021-06-07T10:11:24Z

Some users have pointed out that path-based syscalls are problematic in some environments and at least directory fd argument and possibly also resolve flags are desirable for such syscalls. Rather than reimplementing all details of pathname lookup and following where it may eventually evolve, let's go for full file descriptor based syscall similar to how ioctl(2) works since the beginning. Managing of quotas isn't performance sensitive so the extra overhead of open does not matter and we are able to consume O_PATH descriptors as well which makes open cheap anyway. Also for frequent operations (such as retrieving usage information for all users) we can reuse single fd and in fact get even better performance as well as avoiding races with possible remounts etc. Tested-by: Sascha Hauer Acked-by: Christian Brauner Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara

quota: Use 'hlist_for_each_entry' to simplify code

2021-05-10T14:27:49Z

Use 'hlist_for_each_entry' instead of hand writing it. This saves a few lines of code. Link: https://lore.kernel.org/r/f82d3e33964dcbd2aac19866735e0a8381c8a735.1619599407.git.christophe.jaillet@wanadoo.fr Signed-off-by: Christophe JAILLET Signed-off-by: Jan Kara