Commit Graph

257 Commits

Author SHA1 Message Date
David Sterba
a5d95a73f9 btrfs-progs: add an extensible pointer array struct
API for extensible array of pointers for covenience. A simple wrapper
around a (void *) array with length.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-28 17:24:24 +02:00
David Sterba
ede538f98d btrfs-progs: print null value for empty uuid in json
This is a potentially breaking change to json output. An all zeros uuid
was printed as "-" but we can utilize native json type null for that.
Note the va_copy must be used as va_arg advances the pointer.

{
	"nulluuid": null
}

Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-28 17:24:23 +02:00
David Sterba
70ae158ec8 btrfs-progs: rename time-long format name to date-time
Make the timestamp format more descriptive what is actually printed. We
may need separate date or time in the future.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-28 17:24:23 +02:00
David Sterba
25fc470252 btrfs-progs: print numeric values unquoted in json
The json spec allows numeric values and it's recommended to use them
instead of the stringified numbers. This is a potentially breaking change
if some tools relied on the string value.

As most formats we now have are '%llu' and it's convenient to just pass
it to vprintf, don't add a special type for ints. Any new int type must
be added to the list.

{
	"number": 1234
}

Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-28 17:24:23 +02:00
David Sterba
155eb56417 btrfs-progs: document json format str
The 'str' type was added in ecbb6a7fcd ("btrfs-progs: add json
formatter for escaped string") but not documented. It should be used
e.g. for paths or strings from unknown origin.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-28 17:24:23 +02:00
David Sterba
be5cb7dfe9 btrfs-progs: add bool type to json
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-28 17:24:23 +02:00
David Sterba
b890183072 btrfs-progs: support unquoted values in json
For null or boolean values the "..." quoting must not be done, add
support for that. This is detected internally for each printed value.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-28 17:24:23 +02:00
Christoph Heiss
27a5722fe5 btrfs-progs: common: document time-long output format
Seems this was forgotten; rectify that.

Signed-off-by: Christoph Heiss <christoph@c8h4.io>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-28 17:24:23 +02:00
David Sterba
c135550c28 btrfs-progs: help: indent option description newlines
A newline character in option description text will break line and then
indent the text properly, can be used for lists or paragraphs.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-07-27 14:45:29 +02:00
David Sterba
8922ab5d6a btrfs-progs: add simple error injection framework
To be able to test errors at specific locations, add a simple way to
check for a condition in code and controlled from user space environment
variable INJECT. For now a single value is accepted.

Use like:

	if (inject_error(0x1234)) {
		do_something();
		return -ERROR;
	}

This is enabled in debugging build by default (make D=1) and can be
enabled on demand too (make EXTRA_CFLAGS=-DINJECT).

Signed-off-by: David Sterba <dsterba@suse.com>
2023-07-27 14:45:29 +02:00
David Sterba
b3b041302e btrfs-progs: add btrfs-find-root to btrfs.box
There's a report that btrfs-find-root does not work as built-in tool in
btrfs.box, while it's advertised in the help:

  $ ./btrfs.box help --box
  Standalone tools built-in in the busybox style:
  - mkfs.btrfs
  - btrfs-image
  - btrfs-convert
  - btrfstune
  - btrfs-find-root

Add the support as it might be useful tool sometimes. In the future the
command should be moved to e.g. inspect-internal or rescue.

Issue: #648
Signed-off-by: David Sterba <dsterba@suse.com>
2023-07-26 15:00:48 +02:00
Anand Jain
77f366c9da btrfs-progs: add noscan parameter to check_where_mounted
The function check_where_mounted() scans the system for all other btrfs
devices, which is necessary for its operation.  However, in certain
cases, devices remaining in the scanned state is undesirable.  Introduce
the 'noscan' argument to make devices unscanned before return.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-07-26 15:00:48 +02:00
Anand Jain
e408cfb49b btrfs-progs: factor out btrfs_scan_argv_devices
To prepare for handling command line given devices factor out
btrfs_scan_argv_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-07-26 15:00:48 +02:00
Anand Jain
626d53fc75 btrfs-progs: switch is_btrfs to bool in check_mounted_where
The variable 'is_btrfs' is declared as an integer but should be a boolean
instead.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-07-26 15:00:47 +02:00
David Sterba
e4bb48dcf3 btrfs-progs: sync send.h from kernel
The send.h for libbtrfs has been separated some time ago so we're now
free to keep up with kernel, 6.4-rc1.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:32 +02:00
Qu Wenruo
3ce08b2ff6 btrfs-progs: constify the buffer pointer for write functions
The following functions accept a buffer for write, which can be marked
as const:

- btrfs_pwrite()
- write_data_to_disk()

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:31 +02:00
Qu Wenruo
2b51d006cd btrfs-progs: split btrfs_direct_pio() functions into read and write
It's not a common practice to use the same io function for both read and
write (we have pread() and pwrite(), not pio()).

Furthermore the original function has the following problems:

- Not returning proper error number
  If we had ioctl/stat errors we just return 0 with errno set.
  Thus caller would treat it as a short read, not a proper error.

- Unnecessary @ret_rw
  This is not that obvious if we have different handling for read and
  write, but if we split them it's super obvious we can reuse @ret.

- No proper copy back for short read

- Unable to constify the @buf pointer for write operation

All those problems would be addressed in this patch.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:31 +02:00
Qu Wenruo
b3327119ec btrfs-progs: fix -Wmissing-prototypes warnings
The fixes involve the following changes:

- Unexport functions which are not utilized out of the file
  * print_path_column()
  * parse_reflink_range()
  * btrfs_list_setup_print_column()
  * device_get_partition_size_sysfs()
  * max_zone_append_size()

- Include related headers before implementing the function
  * change-uuid.c
  * convert-bgt.c
  * seed.h

- Add missing headers caused by the above header changes
  * include <uuid/uuid.h> for tune/tune.h.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:31 +02:00
Josef Bacik
bf743c4cf8 btrfs-progs: sync async-thread.[ch] from the kernel
We won't actually use the async code in progs, however we call the
helpers and such all over the normal code, so sync this into btrfs-progs
to make syncing other parts of the kernel easier.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:29 +02:00
David Sterba
164bc10dfc btrfs-progs: add musl compatibility for printf format %pV
Glibc provides an interface to extend the printf formats but this is not
standardized and does not work on musl. The code brought from kernel
uses %pV for varargs and also has own implementation of printk.

As a workaround for musl expand the pV value to a string and then
simply print it. The details are hidden behind macros:

- DECLARE_PV(vaf)
- PV_ASSIGN(vaf, format, args)
- PV_FMT in printf string
- PV_VAL in arguments

Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:28 +02:00
Josef Bacik
762dbd6d70 btrfs-progs: add struct va_format support to our btrfs_no_printk helper
We use the struct va_format to do nested printk's internally with our
message handling.  Add the appropriate user space code to make this work
properly so when we start copying this code into btrfs-progs we get the
proper messages.

Note: this breaks build on musl, printf.h is not available.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:28 +02:00
Josef Bacik
228aa34f10 btrfs-progs: sync messages.[ch] from the kernel
These are the printk helpers from the kernel.  There were a few
modifications, the hi-lights are

- We do not have fs_info::fs_state, so that needed to be removed.
- We do not have discard.h sync'ed yet, so that dependency was dropped.
- Anything related to struct super_block was commented out.
- The transaction abort had to be modified to fit with the current
  btrfs-progs code.
- Added a btrfs_no_printk() helper to common/messages.* so that the
  print statements still worked.
- The 32bit limit checkers are not needed so are behind __KERNEL__

Additionally there were kerncompat.h changes that needed to be made to
handle the dependencies properly.  Those are easier to spot.

Any function that needed to be modified has a MODIFIED tag in the
comment section with a list of things that were changed.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:28 +02:00
Josef Bacik
a754fe29d9 btrfs-progs: sync uapi/btrfs.h into btrfs-progs
We want to keep this file locally as we want to be uptodate with
upstream, so we can build btrfs-progs regardless of which kernel is
currently installed.  Sync this with the upstream version and put it in
kernel-shared/uapi to maintain some semblance of where this file comes
from.

There are some changes that need to be synced back to kernel. A local
definition of static_assert is used to avoid compilation problems on gcc
(< 9) due to mandatory 2nd parameter.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:28 +02:00
Josef Bacik
6636d9a6e2 btrfs-progs: consolidate the btrfs message helpers
These helpers all do variations on the same thing, so add a helper to
just do the printf part, and a macro to handle the special prefix and
postfix, and then make the helpers just use the macro and new helper.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:28 +02:00
Josef Bacik
49581d0556 btrfs-progs: remove the _on() related message helpers
We have different helpers for warning_on and error_on(), which take the
condition and then do the printf.  However we can just check the
condition in the macro and call the normal warning or error helper, so
clean this usage up and delete the unneeded message helpers.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:28 +02:00
Josef Bacik
e051593934 btrfs-progs: move BTRFS_DISABLE_BACKTRACE check in print_trace
Everybody who calls print_trace wraps it around this check, move the
check instead to print_trace and remove the check from all the callers.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:28 +02:00
Josef Bacik
bf0f3db765 btrfs-progs: introduce UASSERT() for purely userspace code
While syncing messages.[ch] I had to back out the ASSERT() code in
kerncompat.h, which means we now rely on the kernel code for ASSERT().
In order to maintain some semblance of separation introduce UASSERT()
and use that in all the purely userspace code.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 18:02:28 +02:00
David Sterba
0251b2f539 btrfs-progs: mkfs: remove block-group-tree from -R
The block-group-tree used to be under experimental flag in -R but now
that we've deprecated -R it does not make sense to leave
block-group-tree there for compatibility, this has never been exposed to
users.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 19:28:05 +02:00
Qu Wenruo
716c3be363 btrfs-progs: move block-group-tree out of experimental features
The feedback from the community on block group tree is very positive,
the only complain is, end users need to recompile btrfs-progs with
experimental features to enjoy the new feature.

So let's move it out of experimental features and let more people enjoy
faster mount speed.

Also change the option of btrfstune, from `-b` to
`--enable-block-group-tree` to avoid short option.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 19:28:05 +02:00
Qu Wenruo
4dbe66ca2f btrfs-progs: mkfs: make -R|--runtime-features option deprecated
The option -R|--runtime-features was introduced to support features that
don't result in a full incompat flag change, thus things like
free-space-tree and quota features are put here.

But to end users, such separation of features is not helpful and can be
sometimes confusing.

Thus we're already migrating those runtime features into -O|--features
option under experimental builds.

I believe this is the proper time to move those runtime features into
-O|--features option, and mark the -R|--runtime-features option
deprecated.

For now we still keep the old option as for compatibility purposes.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 19:27:53 +02:00
David Sterba
6ea85b680b btrfs-progs: path-utils: rename path_is_mount_point to avoid potential symbol name clash
There's a report that a static build fails when there's a static version
of libudev:

  /usr/lib/gcc/x86_64-pc-linux-gnu/12.2.0/../../../../x86_64-pc-linux-gnu/bin/ld: /usr/lib/libudev.a(path-util.o): in function `path_is_mount_point':
  path-util.c:(.text+0xbc0): multiple definition of `path_is_mount_point'; common/path-utils.o:path-utils.c:(.text+0x290): first defined here

There's a helper path_is_mount_point in libudev too but not exported so
dynamic library is fine, unlike static build. The static build of
libudev is not common but we can support that with a simple rename.

Issue: #611
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-03 19:14:13 +02:00
David Sterba
600f374058 btrfs-progs: qgroup show: fix formatting of qgroupid on json output
On a 32bit host the split qgroupid is wrong due to the way the numbers
are passed to the formatter as variable length arguments. The level is
u16, promoted to int and then parsed as u64. This means that the values
are shifted and some stack data are printed instead.

Example error messages from yast2-bootloader:

  SystemCmd.cc(addLine):569 Adding Line 7 "      "qgroupid": "21474836480/23885859321282560","

The value 21474836480 = 0x5000000 is 0x5 shifted by 32 bits,
23885859321282560 is 0x54dc1000000000 and shifting by 32 does not
lead to a valid value which should be 0 in this case.

Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1209136
Signed-off-by: David Sterba <dsterba@suse.com>
2023-03-16 15:48:41 +01:00
David Sterba
4996e4375c btrfs-progs: convert common options to option formatter
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-28 20:11:24 +01:00
Qu Wenruo
f61b90aff9 btrfs-progs: make usage call properly return an exit value
[BUG]
Currently cli/009 test case failed with different exit number:

  ====== RUN CHECK /home/adam/btrfs-progs/btrfstune --help
  usage: btrfstune [options] device
  [...]
  failed: /home/adam/btrfs-progs/btrfstune --help
  test failed for case 009-btrfstune

[CAUSE]
In tune/main.c, we have the following call on usage():

  static void print_usage(int ret)
  {
	usage(&tune_cmd);
	exit(ret);
  }

However usage() itself would always call exit(1):

  void usage(const struct cmd_struct *cmd)
  {
	usage_command_usagestr(cmd->usagestr, NULL, 0, true, true);
	exit(1);
  }

This makes prevents any caller of usage() to modify its exit number.

[FIX]
Add a new argument @error for print_usage(), so we can properly return 0
for -h/--help usage.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-28 20:11:23 +01:00
David Sterba
7fba4bf4db btrfs-progs: add special CPU flag bit representing no features
Add CPU_FLAG_NONE that's first in the list and represents a CPU without
any acceleration features. Can be used for reference/fallback
implementation.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-28 19:49:31 +01:00
David Sterba
3157c572e1 btrfs-progs: add run-time CPU feature detection
Add support for run-time detection of CPU features on x86_64 to allow
selection of accelerated implementations of hash algorithms.

When possible use the compiler builtin (works on gcc and clang).
The SHA extensions can't be detected by __builtin_cpu_supports and the
__cpuid/__cpuidex macros are not consistently provided in all supported
gcc and clang versions. Copy the __cpuidex and call it manually for the
SHA extensions. Complete list https://en.wikipedia.org/wiki/CPUID .

Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-18 17:44:03 +01:00
Qu Wenruo
3a1d4aa089 btrfs-progs: fix fallthrough cases with proper attributes
[FALSE ALERT]
Unlike gcc, clang doesn't really understand the comments, thus it's
reportings tons of fall through related errors:

  cmds/reflink.c:124:3: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
                  case 'r':
                  ^
  cmds/reflink.c:124:3: note: insert '__attribute__((fallthrough));' to silence this warning
                  case 'r':
                  ^
                  __attribute__((fallthrough));
  cmds/reflink.c:124:3: note: insert 'break;' to avoid fall-through
                  case 'r':
                  ^
                  break;

[CAUSE]
Although gcc is fine with /* fallthrough */ comments, clang is not.

[FIX]
So just introduce a fallthrough macro to handle the situation properly,
and use that macro instead.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-18 17:44:02 +01:00
David Sterba
c719f20b74 btrfs-progs: help: change how padding is printed
Use the configured widths and print padding directly instead of the
embedded printf format and fixed width strings.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-01-25 19:55:47 +01:00
David Sterba
fede0c5057 btrfs-progs: help: add option text formatting infrastructure
To make option formatting a bit easier so the spacing is unified add
macros and formatting helpers.

Usage in the help text:

	OPTLINE("-o value", "description")

Internally the option and description are delimiters by chars that are
not part of normal text, the formatter separates that and uses fixed
with for output. The description text can be of any length, multi-line
text should still end up as one token (i.e. newline without ',' between).

Signed-off-by: David Sterba <dsterba@suse.com>
2023-01-25 19:55:47 +01:00
David Sterba
ecbb6a7fcd btrfs-progs: add json formatter for escaped string
Add formatter type 'str' where the string must be escaped, e.g. paths or
internal data. Otherwise plain %s can be printed if it's known that
there are no special characters.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-16 00:40:32 +01:00
David Sterba
6ecaa3ee4f btrfs-progs: qgroup show: add json output
Support json for 'qgroup show' with values printed by "btrfs qgroup
-pcre", the accounted size and the limits.  It's implemented as a
separate call and not sharing the printing routines so any visible
changes need to by synchronized.

Formatter updates: don't print key name if .out_json is NULL.

Example output:

 # btrfs --format json qgroup show /mnt/path
{
  "__header": {
    "version": "1"
  },
  "qgroup-show": [
    {
      "qgroupid": "0/5",
      "referenced": "8831393792",
      "max_referenced": "none",
      "exclusive": "8224075776",
      "max_exclusive": "none",
      "path": "",
      "parents": [
      ],
      "children": [
      ]
    },
    {
      "qgroupid": "0/361",
      "referenced": "611459072",
      "max_referenced": "none",
      "exclusive": "65536",
      "max_exclusive": "none",
      "path": "subv1",
      "parents": [
        "1/1"
      ],
      "children": [
      ]
    },
    {
      "qgroupid": "0/362",
      "referenced": "611459072",
      "max_referenced": "none",
      "exclusive": "65536",
      "max_exclusive": "none",
      "path": "snap1-r",
      "parents": [
      ],
      "children": [
      ]
    },
    {
      "qgroupid": "1/1",
      "referenced": "611459072",
      "max_referenced": "none",
      "exclusive": "65536",
      "max_exclusive": "none",
      "path": "",
      "parents": [
      ],
      "children": [
        "0/361"
      ]
    }
  ]
}

Issue: #555
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-14 23:42:03 +01:00
David Sterba
8195508f37 btrfs-progs: string-table: add ranged API for printing and clearing
Track how many rows belong to a header (names and separators) so they
can be printed or cleared separately. The rest is body that could be
cleared and filled repeatedly. The ranged API allows to print any number
of rows if the table is filled partially.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 20:32:02 +01:00
David Sterba
b397e0eb63 btrfs-progs: string-table: check bounds before writing to a cell
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 20:32:02 +01:00
David Sterba
9cae43183e btrfs-progs: string-table: cleanup and enhance formatting capabilities
Cleanups are for integer types, prototypes and comments.

New functionality: spacing can be set after table allocation as
->spacing, now able to print 1 or 2 spaces between columns.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 20:32:02 +01:00
Josef Bacik
788a71c16a btrfs-progs: sync compression.h from the kernel
This patch copies in compression.h from the kernel.  This is relatively
straightforward, we just have to drop the compression types definition
from ctree.h, and update the image to use BTRFS_NR_COMPRESS_TYPES
instead of BTRFS_COMPRESS_LAST, and add a few things to kerncompat.h to
make everything build smoothly.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-11-30 19:14:29 +01:00
Josef Bacik
557d2617bc btrfs-progs: ioctl: move btrfs_err_str into common/utils.h
This doesn't really belong with the ioctl definitions, and when we sync
the ioctl definitions with the kernel this helper will go away, so
adjust this now.

The ioctl.h is a public API header but the helper is not used in any 3rd
party tool so we can safely move it.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-11-28 18:57:43 +01:00
Filipe Manana
60b920d618 btrfs-progs: receive: fix parsing of attributes field from the fileattr command
We're trying to get a U32 for the attributes, but the kernel sends a U64
(which is correct as we store attributes in a u64 flags field of the
inode). This makes anyone trying to receive a v2 send stream to fail with:

    ERROR: invalid size for attribute, expected = 4, got = 8

We actually recently got such a report of someone using send stream v2 and
getting such failure. See the Link tag below.

Link: https://lore.kernel.org/linux-btrfs/6cb11fa5-c60d-e65b-0295-301a694e66ad@inbox.ru/
Fixes: 7a6fb356dc ("btrfs-progs: receive: process setflags ioctl commands")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-11-24 17:29:11 +01:00
David Sterba
e0cc76a9ce btrfs-progs: add warning helper for experimental build
We should warn that there's an experimental feature used. Add a helper
with optional description. Should be used only if such feature is used
and not always.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-10-20 16:29:13 +02:00
David Sterba
bef462c2e2 btrfs-progs: mkfs: fix compat version of block-group-tree
The -O and -R help texts say that compatible version for
block-group-tree is 6.0 but it's in fact 6.1.

Issue: #523
Signed-off-by: David Sterba <dsterba@suse.com>
2022-10-17 15:46:37 +02:00
Qu Wenruo
d8f1bd519f btrfs-progs: mkfs: fix a stack over-flow when features string are too long
[BUG]
Even with chunk_objectid bug fixed, mkfs.btrfs can still caused stack
overflow when enabling extent-tree-v2 feature (need experimental
features enabled):

  # ./mkfs.btrfs  -f -O extent-tree-v2 ~/test.img
  btrfs-progs v5.19.1
  See http://btrfs.wiki.kernel.org for more information.

  ERROR: superblock magic doesn't match
  NOTE: several default settings have changed in version 5.15, please make sure
        this does not affect your deployments:
        - DUP for metadata (-m dup)
        - enabled no-holes (-O no-holes)
        - enabled free-space-tree (-R free-space-tree)

  Label:              (null)
  UUID:               205c61e7-f58e-4e8f-9dc2-38724f5c554b
  Node size:          16384
  Sector size:        4096
  Filesystem size:    512.00MiB
  Block group profiles:
    Data:             single            8.00MiB
    Metadata:         DUP              32.00MiB
    System:           DUP               8.00MiB
  SSD detected:       no
  Zoned device:       no
  =================================================================
  [... Skip full ASAN output ...]
  ==65655==ABORTING

[CAUSE]
For experimental build, we have unified feature output, but the old
buffer size is only 64 bytes, which is too small to cover the new full
feature string:

  extref, skinny-metadata, no-holes, free-space-tree, block-group-tree, extent-tree-v2

Above feature string is already 84 bytes, over the 64 on-stack memory
size.

This can also be proved by the ASAN output:

  ==65655==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffc4e03b1d0 at pc 0x7ff0fc05fafe bp 0x7ffc4e03ac60 sp 0x7ffc4e03a408
  WRITE of size 17 at 0x7ffc4e03b1d0 thread T0
      #0 0x7ff0fc05fafd in __interceptor_strcat /usr/src/debug/gcc/libsanitizer/asan/asan_interceptors.cpp:377
      #1 0x55cdb7b06ca5 in parse_features_to_string common/fsfeatures.c:316
      #2 0x55cdb7b06ce1 in btrfs_parse_fs_features_to_string common/fsfeatures.c:324
      #3 0x55cdb7a37226 in main mkfs/main.c:1783
      #4 0x7ff0fbe3c28f  (/usr/lib/libc.so.6+0x2328f)
      #5 0x7ff0fbe3c349 in __libc_start_main (/usr/lib/libc.so.6+0x23349)
      #6 0x55cdb7a2cb34 in _start ../sysdeps/x86_64/start.S:115

[FIX]
Introduce a new macro, BTRFS_FEATURE_STRING_BUF_SIZE, along with a new
sanity check helper, btrfs_assert_feature_buf_size().

The problem is I can not find a build time method to verify
BTRFS_FEATURE_STRING_BUF_SIZE is large enough to contain all feature
names, thus have to go the runtime function to do the BUG_ON() to verify
the macro size.

Now the minimal buffer size for experimental build is 138 bytes, just
bump it to 160 for future expansion.

And if further features go beyond that number, mkfs.btrfs/btrfs-convert
will immediately crash at that BUG_ON(), so we can definitely detect it.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-10-11 09:08:12 +02:00