Fix build warnings of function signature when CONFIG_STACKTRACE is not
enabled by reordering the 'inline' and 'void' keywords.
../fs/btrfs/ref-verify.c:221:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration]
static void inline __save_stack_trace(struct ref_action *ra)
../fs/btrfs/ref-verify.c:225:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration]
static void inline __print_stack_trace(struct btrfs_fs_info *fs_info,
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
I noticed that shared ref entries in ref-verify didn't have the proper
owner set, which caused me to think there was something seriously wrong.
However the problem is if we have a parent we simply weren't filling out
the owner part of the reference, even though we have it.
Fix this by making sure we set all the proper fields when we modify a
reference, this way we'll have the proper owner if a problem happens and
we don't waste time thinking we're updating the wrong level.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
I noticed that sometimes I would have the wrong level printed out with
ref-verify while testing some error injection related problems. This is
because we only get the level from the main extent item, but our
references could go off the current leaf into another, and at that point
we lose our level.
Fix this by keeping track of the last tree block level that we found,
the same way we keep track of our bytenr and num_bytes, in case we
happen to wander into another leaf while still processing the references
for a bytenr.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're open-coding btrfs_read_node_slot() here, replace with the helper.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we're using a rw_semaphore we no longer need to indicate if a
lock is blocking or not, nor do we need to flip the entire path from
blocking to spinning. Remove these helpers and all the places they are
called.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Long time ago the explicit casts were necessary for u64 but we don't
need it. Remove casts where the type matches, leaving only cases that
cast sector_t or loff_t.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is one error handling path that does not free ref, which may cause
a minor memory leak.
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
clang static analysis flags this error
fs/btrfs/ref-verify.c:290:3: warning: Potential leak of memory pointed to by 're' [unix.Malloc]
kfree(be);
^~~~~
The problem is in this block of code:
if (root_objectid) {
struct root_entry *exist_re;
exist_re = insert_root_entry(&exist->roots, re);
if (exist_re)
kfree(re);
}
There is no 'else' block freeing when root_objectid is 0. Add the
missing kfree to the else branch.
Fixes: fd708b81d9 ("Btrfs: add a extent ref verify tool")
CC: stable@vger.kernel.org # 4.19+
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Convert fall through comments to the pseudo-keyword which is now the
preferred way.
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
While debugging I noticed I wasn't getting ref verify errors before
everything blew up. Turns out it's because we don't warn when we try to
add a normal ref via btrfs_inc_ref() if the block entry exists but has 0
references. This is incorrect, we should never be doing anything other
than adding a new extent once a block entry drops to 0 references.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In btrfs_ref_tree_mod(), 'ref' and 'ra' are allocated through kzalloc() and
kmalloc(), respectively. In the following code, if an error occurs, the
execution will be redirected to 'out' or 'out_unlock' and the function will
be exited. However, on some of the paths, 'ref' and 'ra' are not
deallocated, leading to memory leaks. For example, if 'action' is
BTRFS_ADD_DELAYED_EXTENT, add_block_entry() will be invoked. If the return
value indicates an error, the execution will be redirected to 'out'. But,
'ref' is not deallocated on this path, causing a memory leak.
To fix the above issues, deallocate both 'ref' and 'ra' before exiting from
the function when an error is encountered.
CC: stable@vger.kernel.org # 4.15+
Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Coverity caught a case where we could return with a uninitialized value
in ret in process_leaf. This is actually pretty likely because we could
very easily run into a block group item key and have a garbage value in
ret and think there was an errror. Fix this by initializing ret to 0.
Reported-by: Colin Ian King <colin.king@canonical.com>
Fixes: fd708b81d9 ("Btrfs: add a extent ref verify tool")
CC: stable@vger.kernel.org # 4.19+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Hi Linus,
This is my very first pull-request. I've been working full-time as
a kernel developer for more than two years now. During this time I've
been fixing bugs reported by Coverity all over the tree and, as part
of my work, I'm also contributing to the KSPP. My work in the kernel
community has been supervised by Greg KH and Kees Cook.
OK. So, after the quick introduction above, please, pull the following
patches that mark switch cases where we are expecting to fall through.
These patches are part of the ongoing efforts to enable -Wimplicit-fallthrough.
They have been ignored for a long time (most of them more than 3 months,
even after pinging multiple times), which is the reason why I've created
this tree. Most of them have been baking in linux-next for a whole development
cycle. And with Stephen Rothwell's help, we've had linux-next nag-emails
going out for newly introduced code that triggers -Wimplicit-fallthrough
to avoid gaining more of these cases while we work to remove the ones
that are already present.
I'm happy to let you know that we are getting close to completing this
work. Currently, there are only 32 of 2311 of these cases left to be
addressed in linux-next. I'm auditing every case; I take a look into
the code and analyze it in order to determine if I'm dealing with an
actual bug or a false positive, as explained here:
https://lore.kernel.org/lkml/c2fad584-1705-a5f2-d63c-824e9b96cf50@embeddedor.com/
While working on this, I've found and fixed the following missing
break/return bugs, some of them introduced more than 5 years ago:
84242b82d87850b51b6c5e420fe63509186e5034b5be8531817264235ee7cc5034a5d2479826cc865340f23df8df997abeeb2f10d82373307b00c5e65d25ff7a54a7ed5b3e7dc24bfa8f21ad0eaee6199ba8376ce1dc586a60a1a8e9b186f14e57562b4860747828eac5b974bee9cc44ba91162c930e3d0a
Once this work is finish, we'll be able to universally enable
"-Wimplicit-fallthrough" to avoid any of these kinds of bugs from
entering the kernel again.
Thanks
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
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Merge tag 'Wimplicit-fallthrough-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux
Pull Wimplicit-fallthrough updates from Gustavo A. R. Silva:
"Mark switch cases where we are expecting to fall through.
This is part of the ongoing efforts to enable -Wimplicit-fallthrough.
Most of them have been baking in linux-next for a whole development
cycle. And with Stephen Rothwell's help, we've had linux-next
nag-emails going out for newly introduced code that triggers
-Wimplicit-fallthrough to avoid gaining more of these cases while we
work to remove the ones that are already present.
We are getting close to completing this work. Currently, there are
only 32 of 2311 of these cases left to be addressed in linux-next. I'm
auditing every case; I take a look into the code and analyze it in
order to determine if I'm dealing with an actual bug or a false
positive, as explained here:
https://lore.kernel.org/lkml/c2fad584-1705-a5f2-d63c-824e9b96cf50@embeddedor.com/
While working on this, I've found and fixed the several missing
break/return bugs, some of them introduced more than 5 years ago.
Once this work is finished, we'll be able to universally enable
"-Wimplicit-fallthrough" to avoid any of these kinds of bugs from
entering the kernel again"
* tag 'Wimplicit-fallthrough-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (27 commits)
memstick: mark expected switch fall-throughs
drm/nouveau/nvkm: mark expected switch fall-throughs
NFC: st21nfca: Fix fall-through warnings
NFC: pn533: mark expected switch fall-throughs
block: Mark expected switch fall-throughs
ASN.1: mark expected switch fall-through
lib/cmdline.c: mark expected switch fall-throughs
lib: zstd: Mark expected switch fall-throughs
scsi: sym53c8xx_2: sym_nvram: Mark expected switch fall-through
scsi: sym53c8xx_2: sym_hipd: mark expected switch fall-throughs
scsi: ppa: mark expected switch fall-through
scsi: osst: mark expected switch fall-throughs
scsi: lpfc: lpfc_scsi: Mark expected switch fall-throughs
scsi: lpfc: lpfc_nvme: Mark expected switch fall-through
scsi: lpfc: lpfc_nportdisc: Mark expected switch fall-through
scsi: lpfc: lpfc_hbadisc: Mark expected switch fall-throughs
scsi: lpfc: lpfc_els: Mark expected switch fall-throughs
scsi: lpfc: lpfc_ct: Mark expected switch fall-throughs
scsi: imm: mark expected switch fall-throughs
scsi: csiostor: csio_wr: mark expected switch fall-through
...
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Merge tag 'for-5.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"This time the majority of changes are cleanups, though there's still a
number of changes of user interest.
User visible changes:
- better read time and write checks to catch errors early and before
writing data to disk (to catch potential memory corruption on data
that get checksummed)
- qgroups + metadata relocation: last speed up patch int the series
to address the slowness, there should be no overhead comparing
balance with and without qgroups
- FIEMAP ioctl does not start a transaction unnecessarily, this can
result in a speed up and less blocking due to IO
- LOGICAL_INO (v1, v2) does not start transaction unnecessarily, this
can speed up the mentioned ioctl and scrub as well
- fsync on files with many (but not too many) hardlinks is faster,
finer decision if the links should be fsynced individually or
completely
- send tries harder to find ranges to clone
- trim/discard will skip unallocated chunks that haven't been touched
since the last mount
Fixes:
- send flushes delayed allocation before start, otherwise it could
miss some changes in case of a very recent rw->ro switch of a
subvolume
- fix fallocate with qgroups that could lead to space accounting
underflow, reported as a warning
- trim/discard ioctl honours the requested range
- starting send and dedupe on a subvolume at the same time will let
only one of them succeed, this is to prevent changes that send
could miss due to dedupe; both operations are restartable
Core changes:
- more tree-checker validations, errors reported by fuzzing tools:
- device item
- inode item
- block group profiles
- tracepoints for extent buffer locking
- async cow preallocates memory to avoid errors happening too deep in
the call chain
- metadata reservations for delalloc reworked to better adapt in
many-writers/low-space scenarios
- improved space flushing logic for intense DIO vs buffered workloads
- lots of cleanups
- removed unused struct members
- redundant argument removal
- properties and xattrs
- extent buffer locking
- selftests
- use common file type conversions
- many-argument functions reduction"
* tag 'for-5.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (227 commits)
btrfs: Use kvmalloc for allocating compressed path context
btrfs: Factor out common extent locking code in submit_compressed_extents
btrfs: Set io_tree only once in submit_compressed_extents
btrfs: Replace clear_extent_bit with unlock_extent
btrfs: Make compress_file_range take only struct async_chunk
btrfs: Remove fs_info from struct async_chunk
btrfs: Rename async_cow to async_chunk
btrfs: Preallocate chunks in cow_file_range_async
btrfs: reserve delalloc metadata differently
btrfs: track DIO bytes in flight
btrfs: merge calls of btrfs_setxattr and btrfs_setxattr_trans in btrfs_set_prop
btrfs: delete unused function btrfs_set_prop_trans
btrfs: start transaction in xattr_handler_set_prop
btrfs: drop local copy of inode i_mode
btrfs: drop old_fsflags in btrfs_ioctl_setflags
btrfs: modify local copy of btrfs_inode flags
btrfs: drop useless inode i_flags copy and restore
btrfs: start transaction in btrfs_ioctl_setflags()
btrfs: export btrfs_set_prop
btrfs: refactor btrfs_set_props to validate externally
...
It's a perfect match for btrfs_ref_tree_mod() to use btrfs_ref, as
btrfs_ref describes a metadata/data reference update comprehensively.
Now we have one less function use confusing owner/level trick.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
This patch fixes the following warnings:
fs/affs/affs.h:124:38: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1692:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1694:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ceph/file.c:249:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:233:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:246:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1237:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1244:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1182:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1188:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1432:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1440:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:618:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:620:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/btrfs/ref-verify.c:522:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:711:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:722:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/jffs2/fs.c:339:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/nfsd/nfs4proc.c:429:12: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:62:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:43:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/fcntl.c:770:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/seq_file.c:319:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:148:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:150:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/signalfd.c:178:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/locks.c:1473:16: warning: this statement may fall through [-Wimplicit-fallthrough=]
Warning level 3 was used: -Wimplicit-fallthrough=3
This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
We can use the right helper where the lock type is a fixed parameter.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
The typos accumulate over time so once in a while time they get fixed in
a large patch.
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are two members in struct btrfs_root which indicate root's
objectid: objectid and root_key.objectid.
They are both set to the same value in __setup_root():
static void __setup_root(struct btrfs_root *root,
struct btrfs_fs_info *fs_info,
u64 objectid)
{
...
root->objectid = objectid;
...
root->root_key.objectid = objecitd;
...
}
and not changed to other value after initialization.
grep in btrfs directory shows both are used in many places:
$ grep -rI "root->root_key.objectid" | wc -l
133
$ grep -rI "root->objectid" | wc -l
55
(4.17, inc. some noise)
It is confusing to have two similar variable names and it seems
that there is no rule about which should be used in a certain case.
Since ->root_key itself is needed for tree reloc tree, let's remove
'objecitd' member and unify code to use ->root_key.objectid in all places.
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Remove GPL boilerplate text (long, short, one-line) and keep the rest,
ie. personal, company or original source copyright statements. Add the
SPDX header.
Signed-off-by: David Sterba <dsterba@suse.com>
We have several reports about node pointer points to incorrect child
tree blocks, which could have even wrong owner and level but still with
valid generation and checksum.
Although btrfs check could handle it and print error message like:
leaf parent key incorrect 60670574592
Kernel doesn't have enough check on this type of corruption correctly.
At least add such check to read_tree_block() and btrfs_read_buffer(),
where we need two new parameters @level and @first_key to verify the
child tree block.
The new @level check is mandatory and all call sites are already
modified to extract expected level from its call chain.
While @first_key is optional, the following call sites are skipping such
check:
1) Root node/leaf
As ROOT_ITEM doesn't contain the first key, skip @first_key check.
2) Direct backref
Only parent bytenr and level is known and we need to resolve the key
all by ourselves, skip @first_key check.
Another note of this verification is, it needs extra info from nodeptr
or ROOT_ITEM, so it can't fit into current tree-checker framework, which
is limited to node/leaf boundary.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With gcc-4.1.2:
fs/btrfs/ref-verify.c: In function ‘btrfs_build_ref_tree’:
fs/btrfs/ref-verify.c:1017: warning: ‘root’ is used uninitialized in this function
The variable is indeed passed uninitialized, but it is never used by the
callee. However, not all versions of gcc are smart enough to notice.
Hence remove the unused parameter from walk_up_tree() to silence the
compiler warning.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David Sterba <dsterba@suse.com>
We were having corruption issues that were tied back to problems with
the extent tree. In order to track them down I built this tool to try
and find the culprit, which was pretty successful. If you compile with
this tool on it will live verify every ref update that the fs makes and
make sure it is consistent and valid. I've run this through with
xfstests and haven't gotten any false positives. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update error messages, add fixup from Dan Carpenter to handle errors
of read_tree_block ]
Signed-off-by: David Sterba <dsterba@suse.com>