pm24.git/fs/ext4/namei.c, branch v4.7

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2016-05-24T19:55:26Z

Pull ext4 updates from Ted Ts'o: "Fix a number of bugs, most notably a potential stale data exposure after a crash and a potential BUG_ON crash if a file has the data journalling flag enabled while it has dirty delayed allocation blocks that haven't been written yet. Also fix a potential crash in the new project quota code and a maliciously corrupted file system. In addition, fix some DAX-specific bugs, including when there is a transient ENOSPC situation and races between writes via direct I/O and an mmap'ed segment that could lead to lost I/O. Finally the usual set of miscellaneous cleanups" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits) ext4: pre-zero allocated blocks for DAX IO ext4: refactor direct IO code ext4: fix race in transient ENOSPC detection ext4: handle transient ENOSPC properly for DAX dax: call get_blocks() with create == 1 for write faults to unwritten extents ext4: remove unmeetable inconsisteny check from ext4_find_extent() jbd2: remove excess descriptions for handle_s ext4: remove unnecessary bio get/put ext4: silence UBSAN in ext4_mb_init() ext4: address UBSAN warning in mb_find_order_for_block() ext4: fix oops on corrupted filesystem ext4: fix check of dqget() return value in ext4_ioctl_setproject() ext4: clean up error handling when orphan list is corrupted ext4: fix hang when processing corrupted orphaned inode list ext4: remove trailing \n from ext4_warning/ext4_error calls ext4: fix races between changing inode journal mode and ext4_writepages ext4: handle unwritten or delalloc buffers before enabling data journaling ext4: fix jbd2 handle extension in ext4_ext_truncate_extend_restart() ext4: do not ask jbd2 to write data for delalloc buffers jbd2: add support for avoiding data writes during transaction commits ...

ext4: fix oops on corrupted filesystem

2016-05-05T15:10:15Z

When filesystem is corrupted in the right way, it can happen ext4_mark_iloc_dirty() in ext4_orphan_add() returns error and we subsequently remove inode from the in-memory orphan list. However this deletion is done with list_del(&EXT4_I(inode)->i_orphan) and thus we leave i_orphan list_head with a stale content. Later we can look at this content causing list corruption, oops, or other issues. The reported trace looked like: WARNING: CPU: 0 PID: 46 at lib/list_debug.c:53 __list_del_entry+0x6b/0x100() list_del corruption, 0000000061c1d6e0->next is LIST_POISON1 0000000000100100) CPU: 0 PID: 46 Comm: ext4.exe Not tainted 4.1.0-rc4+ #250 Stack: 60462947 62219960 602ede24 62219960 602ede24 603ca293 622198f0 602f02eb 62219950 6002c12c 62219900 601b4d6b Call Trace: [<6005769c>] ? vprintk_emit+0x2dc/0x5c0 [<602ede24>] ? printk+0x0/0x94 [<600190bc>] show_stack+0xdc/0x1a0 [<602ede24>] ? printk+0x0/0x94 [<602ede24>] ? printk+0x0/0x94 [<602f02eb>] dump_stack+0x2a/0x2c [<6002c12c>] warn_slowpath_common+0x9c/0xf0 [<601b4d6b>] ? __list_del_entry+0x6b/0x100 [<6002c254>] warn_slowpath_fmt+0x94/0xa0 [<602f4d09>] ? __mutex_lock_slowpath+0x239/0x3a0 [<6002c1c0>] ? warn_slowpath_fmt+0x0/0xa0 [<60023ebf>] ? set_signals+0x3f/0x50 [<600a205a>] ? kmem_cache_free+0x10a/0x180 [<602f4e88>] ? mutex_lock+0x18/0x30 [<601b4d6b>] __list_del_entry+0x6b/0x100 [<601177ec>] ext4_orphan_del+0x22c/0x2f0 [<6012f27c>] ? __ext4_journal_start_sb+0x2c/0xa0 [<6010b973>] ? ext4_truncate+0x383/0x390 [<6010bc8b>] ext4_write_begin+0x30b/0x4b0 [<6001bb50>] ? copy_from_user+0x0/0xb0 [<601aa840>] ? iov_iter_fault_in_readable+0xa0/0xc0 [<60072c4f>] generic_perform_write+0xaf/0x1e0 [<600c4166>] ? file_update_time+0x46/0x110 [<60072f0f>] __generic_file_write_iter+0x18f/0x1b0 [<6010030f>] ext4_file_write_iter+0x15f/0x470 [<60094e10>] ? unlink_file_vma+0x0/0x70 [<6009b180>] ? unlink_anon_vmas+0x0/0x260 [<6008f169>] ? free_pgtables+0xb9/0x100 [<600a6030>] __vfs_write+0xb0/0x130 [<600a61d5>] vfs_write+0xa5/0x170 [<600a63d6>] SyS_write+0x56/0xe0 [<6029fcb0>] ? __libc_waitpid+0x0/0xa0 [<6001b698>] handle_syscall+0x68/0x90 [<6002633d>] userspace+0x4fd/0x600 [<6002274f>] ? save_registers+0x1f/0x40 [<60028bd7>] ? arch_prctl+0x177/0x1b0 [<60017bd5>] fork_handler+0x85/0x90 Fix the problem by using list_del_init() as we always should with i_orphan list. CC: stable@vger.kernel.org Reported-by: Vegard Nossum Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o

ext4: remove trailing \n from ext4_warning/ext4_error calls

2016-04-27T05:11:21Z

Messages passed to ext4_warning() or ext4_error() don't need trailing newlines, because these function add the newlines themselves. Signed-off-by: Jakub Wilk

ext4: allow readdir()'s of large empty directories to be interrupted

2016-04-24T02:50:07Z

If a directory has a large number of empty blocks, iterating over all of them can take a long time, leading to scheduler warnings and users getting irritated when they can't kill a process in the middle of one of these long-running readdir operations. Fix this by adding checks to ext4_readdir() and ext4_htree_fill_tree(). This was reverted earlier due to a typo in the original commit where I experimented with using signal_pending() instead of fatal_signal_pending(). The test was in the wrong place if we were going to return signal_pending() since we would end up returning duplicant entries. See 9f2394c9be47 for a more detailed explanation. Added fix as suggested by Linus to check for signal_pending() in in the filldir() functions. Reported-by: Benjamin LaHaise Google-Bug-Id: 27880676 Signed-off-by: Theodore Ts'o

Revert "ext4: allow readdir()'s of large empty directories to be interrupted"

2016-04-10T23:52:24Z

This reverts commit 1028b55bafb7611dda1d8fed2aeca16a436b7dff. It's broken: it makes ext4 return an error at an invalid point, causing the readdir wrappers to write the the position of the last successful directory entry into the position field, which means that the next readdir will now return that last successful entry _again_. You can only return fatal errors (that terminate the readdir directory walk) from within the filesystem readdir functions, the "normal" errors (that happen when the readdir buffer fills up, for example) happen in the iterorator where we know the position of the actual failing entry. I do have a very different patch that does the "signal_pending()" handling inside the iterator function where it is allowable, but while that one passes all the sanity checks, I screwed up something like four times while emailing it out, so I'm not going to commit it today. So my track record is not good enough, and the stars will have to align better before that one gets committed. And it would be good to get some review too, of course, since celestial alignments are always an iffy debugging model. IOW, let's just revert the commit that caused the problem for now. Reported-by: Greg Thelen Cc: Theodore Ts'o Signed-off-by: Linus Torvalds

don't bother with ->d_inode->i_sb - it's always equal to ->d_sb

2016-04-10T21:11:51Z

... and neither can ever be NULL Signed-off-by: Al Viro

ext4: allow readdir()'s of large empty directories to be interrupted

2016-03-31T02:36:24Z

ext4 crypto: move context consistency check to ext4_file_open()

2016-02-08T05:54:26Z

In the case where the per-file key for the directory is cached, but root does not have access to the key needed to derive the per-file key for the files in the directory, we allow the lookup to succeed, so that lstat(2) and unlink(2) can suceed. However, if a program tries to open the file, it will get an ENOKEY error. Signed-off-by: Theodore Ts'o

ext4 crypto: revalidate dentry after adding or removing the key

2016-02-08T00:35:05Z

Add a validation check for dentries for encrypted directory to make sure we're not caching stale data after a key has been added or removed. Also check to make sure that status of the encryption key is updated when readdir(2) is executed. Signed-off-by: Theodore Ts'o

wrappers for ->i_mutex access

2016-01-22T23:04:28Z

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro