- 30 4月, 2017 2 次提交
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由 Eric Biggers 提交于
There's no difference between ext4_xattr_list() and ext4_listxattr(), so merge them together and just have ext4_listxattr(). Some years ago they took different arguments, but that's no longer the case. Signed-off-by: NEric Biggers <ebiggers@google.com> Reviewed-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Eric Biggers 提交于
Constify static data in ext4 that is never (intentionally) modified so that it is placed in .rodata and benefits from memory protection. Signed-off-by: NEric Biggers <ebiggers@google.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 26 3月, 2017 1 次提交
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由 Theodore Ts'o 提交于
We must lock the xattr block before calculating or verifying the checksum in order to avoid spurious checksum failures. https://bugzilla.kernel.org/show_bug.cgi?id=193661Reported-by: NColin Ian King <colin.king@canonical.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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- 05 2月, 2017 1 次提交
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由 Theodore Ts'o 提交于
Add a shutdown bit that will cause ext4 processing to fail immediately with EIO. Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 12 1月, 2017 1 次提交
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由 Theodore Ts'o 提交于
The xattr_sem deadlock problems fixed in commit 2e81a4ee: "ext4: avoid deadlock when expanding inode size" didn't include the use of xattr_sem in fs/ext4/inline.c. With the addition of project quota which added a new extra inode field, this exposed deadlocks in the inline_data code similar to the ones fixed by 2e81a4ee. The deadlock can be reproduced via: dmesg -n 7 mke2fs -t ext4 -O inline_data -Fq -I 256 /dev/vdc 32768 mount -t ext4 -o debug_want_extra_isize=24 /dev/vdc /vdc mkdir /vdc/a umount /vdc mount -t ext4 /dev/vdc /vdc echo foo > /vdc/a/foo and looks like this: [ 11.158815] [ 11.160276] ============================================= [ 11.161960] [ INFO: possible recursive locking detected ] [ 11.161960] 4.10.0-rc3-00015-g011b30a8a3cf #160 Tainted: G W [ 11.161960] --------------------------------------------- [ 11.161960] bash/2519 is trying to acquire lock: [ 11.161960] (&ei->xattr_sem){++++..}, at: [<c1225a4b>] ext4_expand_extra_isize_ea+0x3d/0x4cd [ 11.161960] [ 11.161960] but task is already holding lock: [ 11.161960] (&ei->xattr_sem){++++..}, at: [<c1227941>] ext4_try_add_inline_entry+0x3a/0x152 [ 11.161960] [ 11.161960] other info that might help us debug this: [ 11.161960] Possible unsafe locking scenario: [ 11.161960] [ 11.161960] CPU0 [ 11.161960] ---- [ 11.161960] lock(&ei->xattr_sem); [ 11.161960] lock(&ei->xattr_sem); [ 11.161960] [ 11.161960] *** DEADLOCK *** [ 11.161960] [ 11.161960] May be due to missing lock nesting notation [ 11.161960] [ 11.161960] 4 locks held by bash/2519: [ 11.161960] #0: (sb_writers#3){.+.+.+}, at: [<c11a2414>] mnt_want_write+0x1e/0x3e [ 11.161960] #1: (&type->i_mutex_dir_key){++++++}, at: [<c119508b>] path_openat+0x338/0x67a [ 11.161960] #2: (jbd2_handle){++++..}, at: [<c123314a>] start_this_handle+0x582/0x622 [ 11.161960] #3: (&ei->xattr_sem){++++..}, at: [<c1227941>] ext4_try_add_inline_entry+0x3a/0x152 [ 11.161960] [ 11.161960] stack backtrace: [ 11.161960] CPU: 0 PID: 2519 Comm: bash Tainted: G W 4.10.0-rc3-00015-g011b30a8a3cf #160 [ 11.161960] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1 04/01/2014 [ 11.161960] Call Trace: [ 11.161960] dump_stack+0x72/0xa3 [ 11.161960] __lock_acquire+0xb7c/0xcb9 [ 11.161960] ? kvm_clock_read+0x1f/0x29 [ 11.161960] ? __lock_is_held+0x36/0x66 [ 11.161960] ? __lock_is_held+0x36/0x66 [ 11.161960] lock_acquire+0x106/0x18a [ 11.161960] ? ext4_expand_extra_isize_ea+0x3d/0x4cd [ 11.161960] down_write+0x39/0x72 [ 11.161960] ? ext4_expand_extra_isize_ea+0x3d/0x4cd [ 11.161960] ext4_expand_extra_isize_ea+0x3d/0x4cd [ 11.161960] ? _raw_read_unlock+0x22/0x2c [ 11.161960] ? jbd2_journal_extend+0x1e2/0x262 [ 11.161960] ? __ext4_journal_get_write_access+0x3d/0x60 [ 11.161960] ext4_mark_inode_dirty+0x17d/0x26d [ 11.161960] ? ext4_add_dirent_to_inline.isra.12+0xa5/0xb2 [ 11.161960] ext4_add_dirent_to_inline.isra.12+0xa5/0xb2 [ 11.161960] ext4_try_add_inline_entry+0x69/0x152 [ 11.161960] ext4_add_entry+0xa3/0x848 [ 11.161960] ? __brelse+0x14/0x2f [ 11.161960] ? _raw_spin_unlock_irqrestore+0x44/0x4f [ 11.161960] ext4_add_nondir+0x17/0x5b [ 11.161960] ext4_create+0xcf/0x133 [ 11.161960] ? ext4_mknod+0x12f/0x12f [ 11.161960] lookup_open+0x39e/0x3fb [ 11.161960] ? __wake_up+0x1a/0x40 [ 11.161960] ? lock_acquire+0x11e/0x18a [ 11.161960] path_openat+0x35c/0x67a [ 11.161960] ? sched_clock_cpu+0xd7/0xf2 [ 11.161960] do_filp_open+0x36/0x7c [ 11.161960] ? _raw_spin_unlock+0x22/0x2c [ 11.161960] ? __alloc_fd+0x169/0x173 [ 11.161960] do_sys_open+0x59/0xcc [ 11.161960] SyS_open+0x1d/0x1f [ 11.161960] do_int80_syscall_32+0x4f/0x61 [ 11.161960] entry_INT80_32+0x2f/0x2f [ 11.161960] EIP: 0xb76ad469 [ 11.161960] EFLAGS: 00000286 CPU: 0 [ 11.161960] EAX: ffffffda EBX: 08168ac8 ECX: 00008241 EDX: 000001b6 [ 11.161960] ESI: b75e46bc EDI: b7755000 EBP: bfbdb108 ESP: bfbdafc0 [ 11.161960] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b Cc: stable@vger.kernel.org # 3.10 (requires 2e81a4ee as a prereq) Reported-by: NGeorge Spelvin <linux@sciencehorizons.net> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 02 12月, 2016 2 次提交
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由 Eric Biggers 提交于
It was possible for an xattr value to have a very large size, which would then pass validation on 32-bit architectures due to a pointer wraparound. Fix this by validating the size in a way which avoids pointer wraparound. It was also possible that a value's size would fit in the available space but its padded size would not. This would cause an out-of-bounds memory write in ext4_xattr_set_entry when replacing the xattr value. For example, if an xattr value of unpadded size 253 bytes went until the very end of the inode or block, then using setxattr(2) to replace this xattr's value with 256 bytes would cause a write to the 3 bytes past the end of the inode or buffer, and the new xattr value would be incorrectly truncated. Fix this by requiring that the padded size fit in the available space rather than the unpadded size. This patch shouldn't have any noticeable effect on non-corrupted/non-malicious filesystems. Signed-off-by: NEric Biggers <ebiggers@google.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Eric Biggers 提交于
With i_extra_isize equal to or close to the available space, it was possible for us to read past the end of the inode when trying to detect or validate in-inode xattrs. Fix this by checking for the needed extra space first. This patch shouldn't have any noticeable effect on non-corrupted/non-malicious filesystems. Signed-off-by: NEric Biggers <ebiggers@google.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Reviewed-by: NAndreas Dilger <adilger@dilger.ca>
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- 15 11月, 2016 2 次提交
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由 Eric Whitney 提交于
The parameter "handle" isn't used. Signed-off-by: NEric Whitney <enwlinux@gmail.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Deepa Dinamani 提交于
CURRENT_TIME_SEC and CURRENT_TIME are not y2038 safe. current_time() will be transitioned to be y2038 safe along with vfs. current_time() returns timestamps according to the granularities set in the super_block. The granularity check in ext4_current_time() to call current_time() or CURRENT_TIME_SEC is not required. Use current_time() directly to obtain timestamps unconditionally, and remove ext4_current_time(). Quota files are assumed to be on the same filesystem. Hence, use current_time() for these files as well. Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Reviewed-by: NArnd Bergmann <arnd@arndb.de>
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- 15 10月, 2016 2 次提交
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由 Joe Perches 提交于
Recent commits require line continuing printks to always use pr_cont or KERN_CONT. Add these markings to a few more printks. Miscellaneaous: o Integrate the ea_idebug and ea_bdebug macros to use a single call to printk(KERN_DEBUG instead of 3 separate printks o Use the more common varargs macro style Signed-off-by: NJoe Perches <joe@perches.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Reviewed-by: NAndreas Dilger <adilger@dilger.ca>
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由 Eric Biggers 提交于
It should be cpu_to_le32(), not le32_to_cpu(). No change in behavior. Found with sparse, and this was the only endianness warning in fs/ext4/. Signed-off-by: NEric Biggers <ebiggers@google.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Reviewed-by: NJan Kara <jack@suse.cz>
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- 30 8月, 2016 7 次提交
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由 Jan Kara 提交于
Move loop to make enough space in the inode from ext4_expand_extra_isize_ea() into a separate function to make that function smaller and better readable and also to avoid delaration of variables inside a loop block. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
'start' variable is completely unused in ext4_expand_extra_isize_ea(). Variable 'first' is used only once in one place. So just remove them. Variables 'entry' and 'last' are only really used later in the function inside a loop. Move their declarations there. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
Factor out function for moving xattrs from inode into external xattr block from ext4_expand_extra_isize_ea(). That function is already quite long and factoring out this rather standalone functionality helps readability. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
We were checking whether computed offsets do not exceed end of block in ext4_xattr_shift_entries(). However this does not make sense since we always only decrease offsets. So replace that assertion with a check whether we really decrease xattrs value offsets. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
Currently we don't support xattrs with e_value_block set. We don't allow them to pass initial xattr check so there's no point for checking for this later. Since these tests were untested, bugs were creeping in and not all places which should have checked were checking e_value_block anyway. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
Currently we don't support xattrs with values stored out of line. Check for that in ext4_xattr_check_names() to make sure we never work with such xattrs since not all the code counts with that resulting is possible weird corruption issues. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
Conditions checking whether there is enough free space in an xattr block and when xattr is large enough to make enough space in the inode forgot to account for the fact that inode need not be completely filled up with xattrs. Thus we could move unnecessarily many xattrs out of inode or even falsely claim there is not enough space to expand the inode. We also forgot to update the amount of free space in xattr block when moving more xattrs and thus could decide to move too big xattr resulting in unexpected failure. Fix these problems by properly updating free space in the inode and xattr block as we move xattrs. To simplify the math, avoid shifting xattrs after removing each one xattr and instead just shift xattrs only once there is enough free space in the inode. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 12 8月, 2016 2 次提交
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由 Jan Kara 提交于
When we need to move xattrs into external xattr block, we call ext4_xattr_block_set() from ext4_expand_extra_isize_ea(). That may end up calling ext4_mark_inode_dirty() again which will recurse back into the inode expansion code leading to deadlocks. Protect from recursion using EXT4_STATE_NO_EXPAND inode flag and move its management into ext4_expand_extra_isize_ea() since its manipulation is safe there (due to xattr_sem) from possible races with ext4_xattr_set_handle() which plays with it as well. CC: stable@vger.kernel.org # 4.4.x Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
We did not count with the padding of xattr value when computing desired shift of xattrs in the inode when expanding i_extra_isize. As a result we could create unaligned start of inline xattrs. Account for alignment properly. CC: stable@vger.kernel.org # 4.4.x- Signed-off-by: NJan Kara <jack@suse.cz>
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- 11 8月, 2016 2 次提交
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由 Jan Kara 提交于
When multiple xattrs need to be moved out of inode, we did not properly recompute total size of xattr headers in the inode and the new header position. Thus when moving the second and further xattr we asked ext4_xattr_shift_entries() to move too much and from the wrong place, resulting in possible xattr value corruption or general memory corruption. CC: stable@vger.kernel.org # 4.4.x Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
The code in ext4_expand_extra_isize_ea() treated new_extra_isize argument sometimes as the desired target i_extra_isize and sometimes as the amount by which we need to grow current i_extra_isize. These happen to coincide when i_extra_isize is 0 which used to be the common case and so nobody noticed this until recently when we added i_projid to the inode and so i_extra_isize now needs to grow from 28 to 32 bytes. The result of these bugs was that we sometimes unnecessarily decided to move xattrs out of inode even if there was enough space and we often ended up corrupting in-inode xattrs because arguments to ext4_xattr_shift_entries() were just wrong. This could demonstrate itself as BUG_ON in ext4_xattr_shift_entries() triggering. Fix the problem by introducing new isize_diff variable and use it where appropriate. CC: stable@vger.kernel.org # 4.4.x Reported-by: NDave Chinner <david@fromorbit.com> Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 04 7月, 2016 1 次提交
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由 Daeho Jeong 提交于
We temporally change checksum fields in buffers of some types of metadata into '0' for verifying the checksum values. By doing this without locking the buffer, some metadata's checksums, which are being committed or written back to the storage, could be damaged. In our test, several metadata blocks were found with damaged metadata checksum value during recovery process. When we only verify the checksum value, we have to avoid modifying checksum fields directly. Signed-off-by: NDaeho Jeong <daeho.jeong@samsung.com> Signed-off-by: NYoungjin Gil <youngjin.gil@samsung.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
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- 23 3月, 2016 1 次提交
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由 Theodore Ts'o 提交于
We aren't checking to see if the in-inode extended attribute is corrupted before we try to expand the inode's extra isize fields. This can lead to potential crashes caused by the BUG_ON() check in ext4_xattr_shift_entries(). Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 23 2月, 2016 4 次提交
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由 Andreas Gruenbacher 提交于
To reduce amount of damage caused by single bad block, we limit number of inodes sharing an xattr block to 1024. Thus there can be more xattr blocks with the same contents when there are lots of files with the same extended attributes. These xattr blocks naturally result in hash collisions and can form long hash chains and we unnecessarily check each such block only to find out we cannot use it because it is already shared by too many inodes. Add a reusable flag to cache entries which is cleared when a cache entry has reached its maximum refcount. Cache entries which are not marked reusable are skipped by mb_cache_entry_find_{first,next}. This significantly speeds up mbcache when there are many same xattr blocks. For example for xattr-bench with 5 values and each process handling 20000 files, the run for 64 processes is 25x faster with this patch. Even for 8 processes the speedup is almost 3x. We have also verified that for situations where there is only one xattr block of each kind, the patch doesn't have a measurable cost. [JK: Remove handling of setting the same value since it is not needed anymore, check for races in e_reusable setting, improve changelog, add measurements] Signed-off-by: NAndreas Gruenbacher <agruenba@redhat.com> Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
When someone tried to set xattr to the same value (i.e., not changing anything) we did all the work of removing original xattr, possibly breaking references to shared xattr block, inserting new xattr, and merging xattr blocks again. Since this is not so rare operation and it is relatively cheap for us to detect this case, check for this and shortcut xattr setting in that case. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
Since old mbcache code is gone, let's rename new code to mbcache since number 2 is now meaningless. This is just a mechanical replacement. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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由 Jan Kara 提交于
The conversion is generally straightforward. The only tricky part is that xattr block corresponding to found mbcache entry can get freed before we get buffer lock for that block. So we have to check whether the entry is still valid after getting buffer lock. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 07 1月, 2016 1 次提交
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由 Dmitry Monakhov 提交于
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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- 14 12月, 2015 1 次提交
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由 Andreas Gruenbacher 提交于
Change the list operation to only return whether or not an attribute should be listed. Copying the attribute names into the buffer is moved to the callers. Since the result only depends on the dentry and not on the attribute name, we do not pass the attribute name to list operations. Signed-off-by: NAndreas Gruenbacher <agruenba@redhat.com> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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- 14 11月, 2015 1 次提交
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由 Andreas Gruenbacher 提交于
The xattr_handler operations are currently all passed a file system specific flags value which the operations can use to disambiguate between different handlers; some file systems use that to distinguish the xattr namespace, for example. In some oprations, it would be useful to also have access to the handler prefix. To allow that, pass a pointer to the handler to operations instead of the flags value alone. Signed-off-by: NAndreas Gruenbacher <agruenba@redhat.com> Reviewed-by: NChristoph Hellwig <hch@lst.de> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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- 18 10月, 2015 2 次提交
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由 Darrick J. Wong 提交于
Create separate predicate functions to test/set/clear feature flags, thereby replacing the wordy old macros. Furthermore, clean out the places where we open-coded feature tests. Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
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由 Darrick J. Wong 提交于
Instead of overloading EIO for CRC errors and corrupt structures, return the same error codes that XFS returns for the same issues. Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 16 4月, 2015 1 次提交
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由 David Howells 提交于
that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: NDavid Howells <dhowells@redhat.com> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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- 03 4月, 2015 2 次提交
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由 Wei Yuan 提交于
In this if statement, the previous condition is useless, the later one has covered it. Signed-off-by: NWeiyuan <weiyuan.wei@huawei.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Reviewed-by: NLukas Czerner <lczerner@redhat.com>
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由 Sheng Yong 提交于
Remove unused header files and header files which are included in ext4.h. Signed-off-by: NSheng Yong <shengyong1@huawei.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 13 10月, 2014 1 次提交
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由 Dmitry Monakhov 提交于
Besides the fact that this replacement improves code readability it also protects from errors caused direct EXT4_S(sb)->s_es manipulation which may result attempt to use uninitialized csum machinery. #Testcase_BEGIN IMG=/dev/ram0 MNT=/mnt mkfs.ext4 $IMG mount $IMG $MNT #Enable feature directly on disk, on mounted fs tune2fs -O metadata_csum $IMG # Provoke metadata update, likey result in OOPS touch $MNT/test umount $MNT #Testcase_END # Replacement script @@ expression E; @@ - EXT4_HAS_RO_COMPAT_FEATURE(E, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) + ext4_has_metadata_csum(E) https://bugzilla.kernel.org/show_bug.cgi?id=82201Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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- 17 9月, 2014 1 次提交
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由 Darrick J. Wong 提交于
When loading extended attributes, check each entry's value offset to make sure it doesn't collide with the entries. Without this check it is easy to crash the kernel by mounting a malicious FS containing a file with an EA wherein e_value_offs = 0 and e_value_size > 0 and then deleting the EA, which corrupts the name list. (See the f_ea_value_crash test's FS image in e2fsprogs for an example.) Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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- 05 9月, 2014 1 次提交
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由 Theodore Ts'o 提交于
The EXT4_STATE_DELALLOC_RESERVED flag was originally implemented because it was too hard to make sure the mballoc and get_block flags could be reliably passed down through all of the codepaths that end up calling ext4_mb_new_blocks(). Since then, we have mb_flags passed down through most of the code paths, so getting rid of EXT4_STATE_DELALLOC_RESERVED isn't as tricky as it used to. This commit plumbs in the last of what is required, and then adds a WARN_ON check to make sure we haven't missed anything. If this passes a full regression test run, we can then drop EXT4_STATE_DELALLOC_RESERVED. Signed-off-by: NTheodore Ts'o <tytso@mit.edu> Reviewed-by: NJan Kara <jack@suse.cz>
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- 13 5月, 2014 1 次提交
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由 liang xie 提交于
Make them more consistently Signed-off-by: Nxieliang <xieliang@xiaomi.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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