user/sven/linux.git/fs/ext4/ialloc.c, branch v5.7

ext4: increase wait time needed before reuse of deleted inode numbers

2020-04-16T03:58:49Z

Current wait times have proven to be too short to protect against inode reuses that lead to metadata inconsistencies. Now that we will retry the inode allocation if we can't find any recently deleted inodes, it's a lot safer to increase the recently deleted time from 5 seconds to a minute. Link: https://lore.kernel.org/r/20200414023925.273867-1-tytso@mit.edu Google-Bug-Id: 36602237 Signed-off-by: Theodore Ts'o

ext4: fix return-value types in several function comments

2020-04-16T03:58:48Z

The documentation comments for ext4_read_block_bitmap_nowait and ext4_read_inode_bitmap describe them as returning NULL on error, but they return an ERR_PTR on error; update the documentation to match. The documentation comment for ext4_wait_block_bitmap describes it as returning 1 on error, but it returns -errno on error; update the documentation to match. Signed-off-by: Josh Triplett Reviewed-by: Ritesh Harani Link: https://lore.kernel.org/r/60a3f4996f4932c45515aaa6b75ca42f2a78ec9b.1585512514.git.josh@joshtriplett.org Signed-off-by: Theodore Ts'o

ext4: save all error info in save_error_info() and drop ext4_set_errno()

2020-04-01T21:29:06Z

Using a separate function, ext4_set_errno() to set the errno is problematic because it doesn't do the right thing once s_last_error_errorcode is non-zero. It's also less racy to set all of the error information all at once. (Also, as a bonus, it shrinks code size slightly.) Link: https://lore.kernel.org/r/20200329020404.686965-1-tytso@mit.edu Fixes: 878520ac45f9 ("ext4: save the error code which triggered...") Signed-off-by: Theodore Ts'o

ext4: avoid ENOSPC when avoiding to reuse recently deleted inodes

2020-03-26T14:55:00Z

When ext4 is running on a filesystem without a journal, it tries not to reuse recently deleted inodes to provide better chances for filesystem recovery in case of crash. However this logic forbids reuse of freed inodes for up to 5 minutes and especially for filesystems with smaller number of inodes can lead to ENOSPC errors returned when allocating new inodes. Fix the problem by allowing to reuse recently deleted inode if there's no other inode free in the scanned range. Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20200318121317.31941-1-jack@suse.cz Signed-off-by: Theodore Ts'o

ext4: fix potential race between s_flex_groups online resizing and access

2020-02-22T00:31:46Z

During an online resize an array of s_flex_groups structures gets replaced so it can get enlarged. If there is a concurrent access to the array and this memory has been reused then this can lead to an invalid memory access. The s_flex_group array has been converted into an array of pointers rather than an array of structures. This is to ensure that the information contained in the structures cannot get out of sync during a resize due to an accessor updating the value in the old structure after it has been copied but before the array pointer is updated. Since the structures them- selves are no longer copied but only the pointers to them this case is mitigated. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443 Link: https://lore.kernel.org/r/20200221053458.730016-4-tytso@mit.edu Signed-off-by: Suraj Jitindar Singh Signed-off-by: Theodore Ts'o Cc: stable@kernel.org

ext4: simulate various I/O and checksum errors when reading metadata

2019-12-26T16:28:31Z

This allows us to test various error handling code paths Link: https://lore.kernel.org/r/20191209012317.59398-1-tytso@mit.edu Signed-off-by: Theodore Ts'o

ext4: save the error code which triggered an ext4_error() in the superblock

2019-12-26T16:28:23Z

This allows the cause of an ext4_error() report to be categorized based on whether it was triggered due to an I/O error, or an memory allocation error, or other possible causes. Most errors are caused by a detected file system inconsistency, so the default code stored in the superblock will be EXT4_ERR_EFSCORRUPTED. Link: https://lore.kernel.org/r/20191204032335.7683-1-tytso@mit.edu Signed-off-by: Theodore Ts'o

ext4: reserve revoke credits in __ext4_new_inode

2019-12-14T22:47:13Z

It's possible that __ext4_new_inode will release the xattr block, so it will trigger a warning since there is revoke credits will be 0 if the handle == NULL. The below scripts can reproduce it easily. ------------[ cut here ]------------ WARNING: CPU: 0 PID: 3861 at fs/jbd2/revoke.c:374 jbd2_journal_revoke+0x30e/0x540 fs/jbd2/revoke.c:374 ... __ext4_forget+0x1d7/0x800 fs/ext4/ext4_jbd2.c:248 ext4_free_blocks+0x213/0x1d60 fs/ext4/mballoc.c:4743 ext4_xattr_release_block+0x55b/0x780 fs/ext4/xattr.c:1254 ext4_xattr_block_set+0x1c2c/0x2c40 fs/ext4/xattr.c:2112 ext4_xattr_set_handle+0xa7e/0x1090 fs/ext4/xattr.c:2384 __ext4_set_acl+0x54d/0x6c0 fs/ext4/acl.c:214 ext4_init_acl+0x218/0x2e0 fs/ext4/acl.c:293 __ext4_new_inode+0x352a/0x42b0 fs/ext4/ialloc.c:1151 ext4_mkdir+0x2e9/0xbd0 fs/ext4/namei.c:2774 vfs_mkdir+0x386/0x5f0 fs/namei.c:3811 do_mkdirat+0x11c/0x210 fs/namei.c:3834 do_syscall_64+0xa1/0x530 arch/x86/entry/common.c:294 ... ------------------------------------- scripts: mkfs.ext4 /dev/vdb mount /dev/vdb /mnt cd /mnt && mkdir dir && for i in {1..8}; do setfacl -dm "u:user_"$i":rx" dir; done mkdir dir/dir1 && mv dir/dir1 ./ sh repro.sh && add some user [root@localhost ~]# cat repro.sh while [ 1 -eq 1 ]; do rm -rf dir rm -rf dir1/dir1 mkdir dir for i in {1..8}; do setfacl -dm "u:test"$i":rx" dir; done setfacl -m "u:user_9:rx" dir & mkdir dir1/dir1 & done Before exec repro.sh, dir1 has inherit the default acl from dir, and xattr block of dir1 dir is not the same, so the h_refcount of these two dir's xattr block will be 1. Then repro.sh can trigger the warning with the situation show as below. The last h_refcount can be clear with mkdir, and __ext4_new_inode has not reserved revoke credits, so the warning will happened, fix it by reserve revoke credits in __ext4_new_inode. Thread 1 Thread 2 mkdir dir set default acl(will create a xattr block blk1 and the refcount of ext4_xattr_header will be 1) ... mkdir dir1/dir1 ->....->ext4_init_acl ->__ext4_set_acl(set default acl, will reuse blk1, and h_refcount will be 2) setfacl->ext4_set_acl->... ->ext4_xattr_block_set(will create new block blk2 to store xattr) ->__ext4_set_acl(set access acl, since h_refcount of blk1 is 2, will create blk3 to store xattr) ->ext4_xattr_release_block(dec h_refcount of blk1 to 1) ->ext4_xattr_release_block(dec h_refcount and since it is 0, will release the block and trigger the warning) Link: https://lore.kernel.org/r/20191213014900.47228-1-yangerkun@huawei.com Reported-by: Hulk Robot Reviewed-by: Jan Kara Signed-off-by: yangerkun Signed-off-by: Theodore Ts'o

ext4: fix leak of quota reservations

2019-11-15T00:25:47Z

Commit 8fcc3a580651 ("ext4: rework reserved cluster accounting when invalidating pages") moved freeing of delayed allocation reservations from dirty page invalidation time to time when we evict corresponding status extent from extent status tree. For inodes which don't have any blocks allocated this may actually happen only in ext4_clear_blocks() which is after we've dropped references to quota structures from the inode. Thus reservation of quota leaked. Fix the problem by clearing quota information from the inode only after evicting extent status tree in ext4_clear_inode(). Link: https://lore.kernel.org/r/20191108115420.GI20863@quack2.suse.cz Reported-by: Konstantin Khlebnikov Fixes: 8fcc3a580651 ("ext4: rework reserved cluster accounting when invalidating pages") Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o

ext4: Reserve revoke credits for freed blocks

2019-11-05T21:00:49Z

So far we have reserved only relatively high fixed amount of revoke credits for each transaction. We over-reserved by large amount for most cases but when freeing large directories or files with data journalling, the fixed amount is not enough. In fact the worst case estimate is inconveniently large (maximum extent size) for freeing of one extent. We fix this by doing proper estimate of the amount of blocks that need to be revoked when removing blocks from the inode due to truncate or hole punching and otherwise reserve just a small amount of revoke credits for each transaction to accommodate freeing of xattrs block or so. Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20191105164437.32602-23-jack@suse.cz Signed-off-by: Theodore Ts'o