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Commit Graph

664 Commits

Author SHA1 Message Date
Baokun Li
5f48d4d9d8 ext4: save unnecessary indentation in ext4_ext_create_new_leaf()
Save an indentation level in ext4_ext_create_new_leaf() by removing
unnecessary 'else'. Besides, the variable 'ee_block' is declared to
avoid line breaks. No functional changes.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20240822023545.1994557-26-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:14:16 -04:00
Baokun Li
2352e3e461 ext4: make some fast commit functions reuse extents path
The ext4_find_extent() can update the extent path so that it does not have
to allocate and free the path repeatedly, thus reducing the consumption of
memory allocation and freeing in the following functions:

    ext4_ext_clear_bb
    ext4_ext_replay_set_iblocks
    ext4_fc_replay_add_range
    ext4_fc_set_bitmaps_and_counters

No functional changes. Note that ext4_find_extent() does not support error
pointers, so in this case set path to NULL first.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-25-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:14:12 -04:00
Baokun Li
a2c613b8c4 ext4: refactor ext4_swap_extents() to reuse extents path
The ext4_find_extent() can update the extent path so it doesn't have to
allocate and free path repeatedly, thus reducing the consumption of memory
allocation and freeing in ext4_swap_extents().

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-24-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:18 -04:00
Baokun Li
4191eefef9 ext4: get rid of ppath in convert_initialized_extent()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in convert_initialized_extent(), the following is
done here:

 * Free the extents path when an error is encountered.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-23-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:18 -04:00
Baokun Li
2ec2e10434 ext4: get rid of ppath in ext4_ext_handle_unwritten_extents()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_ext_handle_unwritten_extents(), the
following is done here:

 * Free the extents path when an error is encountered.
 * The 'allocated' is changed from passing a value to passing an address.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-22-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:18 -04:00
Baokun Li
33c14b8bd8 ext4: get rid of ppath in ext4_ext_convert_to_initialized()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_ext_convert_to_initialized(), the following
is done here:

 * Free the extents path when an error is encountered.
 * Its caller needs to update ppath if it uses ppath.
 * The 'allocated' is changed from passing a value to passing an address.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-21-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:18 -04:00
Baokun Li
8d5ad7b08f ext4: get rid of ppath in ext4_convert_unwritten_extents_endio()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_convert_unwritten_extents_endio(), the
following is done here:

 * Free the extents path when an error is encountered.
 * Its caller needs to update ppath if it uses ppath.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-20-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:18 -04:00
Baokun Li
225057b1af ext4: get rid of ppath in ext4_split_convert_extents()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_split_convert_extents(), the following is
done here:

 * Its caller needs to update ppath if it uses ppath.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-19-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:18 -04:00
Baokun Li
f74cde0456 ext4: get rid of ppath in ext4_split_extent()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_split_extent(), the following is done here:

 * The 'allocated' is changed from passing a value to passing an address.
 * Its caller needs to update ppath if it uses ppath.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-18-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
f07be1c367 ext4: get rid of ppath in ext4_force_split_extent_at()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_force_split_extent_at(), the following is
done here:

 * Free the extents path when an error is encountered.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-17-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
1de82b1b60 ext4: get rid of ppath in ext4_split_extent_at()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_split_extent_at(), the following is done
here:

 * Free the extents path when an error is encountered.
 * Its caller needs to update ppath if it uses ppath.
 * Teach ext4_ext_show_leaf() to skip error pointer.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-16-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
f7d1331f16 ext4: get rid of ppath in ext4_ext_insert_extent()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_ext_insert_extent(), the following is done
here:

 * Free the extents path when an error is encountered.
 * Its caller needs to update ppath if it uses ppath.
 * Free path when npath is used, free npath when it is not used.
 * The got_allocated_blocks label in ext4_ext_map_blocks() does not
   update err now, so err is updated to 0 if the err returned by
   ext4_ext_search_right() is greater than 0 and is about to enter
   got_allocated_blocks.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-15-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
a000bc8678 ext4: get rid of ppath in ext4_ext_create_new_leaf()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

To get rid of the ppath in ext4_ext_create_new_leaf(), the following is
done here:

 * Free the extents path when an error is encountered.
 * Its caller needs to update ppath if it uses ppath.

No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-14-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
6b854d5527 ext4: get rid of ppath in get_ext_path()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

After getting rid of ppath in get_ext_path(), its caller may pass an error
pointer to ext4_free_ext_path(), so it needs to teach ext4_free_ext_path()
and ext4_ext_drop_refs() to skip the error pointer. No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-13-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
0be4c0c2f1 ext4: get rid of ppath in ext4_find_extent()
The use of path and ppath is now very confusing, so to make the code more
readable, pass path between functions uniformly, and get rid of ppath.

Getting rid of ppath in ext4_find_extent() requires its caller to update
ppath. These ppaths will also be dropped later. No functional changes.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-12-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
369c944ed1 ext4: propagate errors from ext4_find_extent() in ext4_insert_range()
Even though ext4_find_extent() returns an error, ext4_insert_range() still
returns 0. This may confuse the user as to why fallocate returns success,
but the contents of the file are not as expected. So propagate the error
returned by ext4_find_extent() to avoid inconsistencies.

Fixes: 331573febb ("ext4: Add support FALLOC_FL_INSERT_RANGE for fallocate")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-11-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
6c2b3246cd ext4: add new ext4_ext_path_brelse() helper
Add ext4_ext_path_brelse() helper function to reduce duplicate code
and ensure that path->p_bh is set to NULL after it is released.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-10-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
dcaa6c3113 ext4: fix double brelse() the buffer of the extents path
In ext4_ext_try_to_merge_up(), set path[1].p_bh to NULL after it has been
released, otherwise it may be released twice. An example of what triggers
this is as follows:

  split2    map    split1
|--------|-------|--------|

ext4_ext_map_blocks
 ext4_ext_handle_unwritten_extents
  ext4_split_convert_extents
   // path->p_depth == 0
   ext4_split_extent
     // 1. do split1
     ext4_split_extent_at
       |ext4_ext_insert_extent
       |  ext4_ext_create_new_leaf
       |    ext4_ext_grow_indepth
       |      le16_add_cpu(&neh->eh_depth, 1)
       |    ext4_find_extent
       |      // return -ENOMEM
       |// get error and try zeroout
       |path = ext4_find_extent
       |  path->p_depth = 1
       |ext4_ext_try_to_merge
       |  ext4_ext_try_to_merge_up
       |    path->p_depth = 0
       |    brelse(path[1].p_bh)  ---> not set to NULL here
       |// zeroout success
     // 2. update path
     ext4_find_extent
     // 3. do split2
     ext4_split_extent_at
       ext4_ext_insert_extent
         ext4_ext_create_new_leaf
           ext4_ext_grow_indepth
             le16_add_cpu(&neh->eh_depth, 1)
           ext4_find_extent
             path[0].p_bh = NULL;
             path->p_depth = 1
             read_extent_tree_block  ---> return err
             // path[1].p_bh is still the old value
             ext4_free_ext_path
               ext4_ext_drop_refs
                 // path->p_depth == 1
                 brelse(path[1].p_bh)  ---> brelse a buffer twice

Finally got the following WARRNING when removing the buffer from lru:

============================================
VFS: brelse: Trying to free free buffer
WARNING: CPU: 2 PID: 72 at fs/buffer.c:1241 __brelse+0x58/0x90
CPU: 2 PID: 72 Comm: kworker/u19:1 Not tainted 6.9.0-dirty #716
RIP: 0010:__brelse+0x58/0x90
Call Trace:
 <TASK>
 __find_get_block+0x6e7/0x810
 bdev_getblk+0x2b/0x480
 __ext4_get_inode_loc+0x48a/0x1240
 ext4_get_inode_loc+0xb2/0x150
 ext4_reserve_inode_write+0xb7/0x230
 __ext4_mark_inode_dirty+0x144/0x6a0
 ext4_ext_insert_extent+0x9c8/0x3230
 ext4_ext_map_blocks+0xf45/0x2dc0
 ext4_map_blocks+0x724/0x1700
 ext4_do_writepages+0x12d6/0x2a70
[...]
============================================

Fixes: ecb94f5fdf ("ext4: collapse a single extent tree block into the inode if possible")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-9-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
5c0f4cc84d ext4: drop ppath from ext4_ext_replay_update_ex() to avoid double-free
When calling ext4_force_split_extent_at() in ext4_ext_replay_update_ex(),
the 'ppath' is updated but it is the 'path' that is freed, thus potentially
triggering a double-free in the following process:

ext4_ext_replay_update_ex
  ppath = path
  ext4_force_split_extent_at(&ppath)
    ext4_split_extent_at
      ext4_ext_insert_extent
        ext4_ext_create_new_leaf
          ext4_ext_grow_indepth
            ext4_find_extent
              if (depth > path[0].p_maxdepth)
                kfree(path)                 ---> path First freed
                *orig_path = path = NULL    ---> null ppath
  kfree(path)                               ---> path double-free !!!

So drop the unnecessary ppath and use path directly to avoid this problem.
And use ext4_find_extent() directly to update path, avoiding unnecessary
memory allocation and freeing. Also, propagate the error returned by
ext4_find_extent() instead of using strange error codes.

Fixes: 8016e29f43 ("ext4: fast commit recovery path")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-8-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:17 -04:00
Baokun Li
a164f3a432 ext4: aovid use-after-free in ext4_ext_insert_extent()
As Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is
reallocated in ext4_ext_create_new_leaf(), we'll use the stale path and
cause UAF. Below is a sample trace with dummy values:

ext4_ext_insert_extent
  path = *ppath = 2000
  ext4_ext_create_new_leaf(ppath)
    ext4_find_extent(ppath)
      path = *ppath = 2000
      if (depth > path[0].p_maxdepth)
            kfree(path = 2000);
            *ppath = path = NULL;
      path = kcalloc() = 3000
      *ppath = 3000;
      return path;
  /* here path is still 2000, UAF! */
  eh = path[depth].p_hdr

==================================================================
BUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330
Read of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179
CPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866
Call Trace:
 <TASK>
 ext4_ext_insert_extent+0x26d4/0x3330
 ext4_ext_map_blocks+0xe22/0x2d40
 ext4_map_blocks+0x71e/0x1700
 ext4_do_writepages+0x1290/0x2800
[...]

Allocated by task 179:
 ext4_find_extent+0x81c/0x1f70
 ext4_ext_map_blocks+0x146/0x2d40
 ext4_map_blocks+0x71e/0x1700
 ext4_do_writepages+0x1290/0x2800
 ext4_writepages+0x26d/0x4e0
 do_writepages+0x175/0x700
[...]

Freed by task 179:
 kfree+0xcb/0x240
 ext4_find_extent+0x7c0/0x1f70
 ext4_ext_insert_extent+0xa26/0x3330
 ext4_ext_map_blocks+0xe22/0x2d40
 ext4_map_blocks+0x71e/0x1700
 ext4_do_writepages+0x1290/0x2800
 ext4_writepages+0x26d/0x4e0
 do_writepages+0x175/0x700
[...]
==================================================================

So use *ppath to update the path to avoid the above problem.

Reported-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Closes: https://lore.kernel.org/r/ZqyL6rmtwl6N4MWR@li-bb2b2a4c-3307-11b2-a85c-8fa5c3a69313.ibm.com
Fixes: 10809df84a ("ext4: teach ext4_ext_find_extent() to realloc path if necessary")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20240822023545.1994557-7-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:16 -04:00
Baokun Li
5b4b2dcace ext4: update orig_path in ext4_find_extent()
In ext4_find_extent(), if the path is not big enough, we free it and set
*orig_path to NULL. But after reallocating and successfully initializing
the path, we don't update *orig_path, in which case the caller gets a
valid path but a NULL ppath, and this may cause a NULL pointer dereference
or a path memory leak. For example:

ext4_split_extent
  path = *ppath = 2000
  ext4_find_extent
    if (depth > path[0].p_maxdepth)
      kfree(path = 2000);
      *orig_path = path = NULL;
      path = kcalloc() = 3000
  ext4_split_extent_at(*ppath = NULL)
    path = *ppath;
    ex = path[depth].p_ext;
    // NULL pointer dereference!

==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000010
CPU: 6 UID: 0 PID: 576 Comm: fsstress Not tainted 6.11.0-rc2-dirty #847
RIP: 0010:ext4_split_extent_at+0x6d/0x560
Call Trace:
 <TASK>
 ext4_split_extent.isra.0+0xcb/0x1b0
 ext4_ext_convert_to_initialized+0x168/0x6c0
 ext4_ext_handle_unwritten_extents+0x325/0x4d0
 ext4_ext_map_blocks+0x520/0xdb0
 ext4_map_blocks+0x2b0/0x690
 ext4_iomap_begin+0x20e/0x2c0
[...]
==================================================================

Therefore, *orig_path is updated when the extent lookup succeeds, so that
the caller can safely use path or *ppath.

Fixes: 10809df84a ("ext4: teach ext4_ext_find_extent() to realloc path if necessary")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20240822023545.1994557-6-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:16 -04:00
Baokun Li
4e2524ba2c ext4: avoid use-after-free in ext4_ext_show_leaf()
In ext4_find_extent(), path may be freed by error or be reallocated, so
using a previously saved *ppath may have been freed and thus may trigger
use-after-free, as follows:

ext4_split_extent
  path = *ppath;
  ext4_split_extent_at(ppath)
  path = ext4_find_extent(ppath)
  ext4_split_extent_at(ppath)
    // ext4_find_extent fails to free path
    // but zeroout succeeds
  ext4_ext_show_leaf(inode, path)
    eh = path[depth].p_hdr
    // path use-after-free !!!

Similar to ext4_split_extent_at(), we use *ppath directly as an input to
ext4_ext_show_leaf(). Fix a spelling error by the way.

Same problem in ext4_ext_handle_unwritten_extents(). Since 'path' is only
used in ext4_ext_show_leaf(), remove 'path' and use *ppath directly.

This issue is triggered only when EXT_DEBUG is defined and therefore does
not affect functionality.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-5-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:16 -04:00
Baokun Li
c26ab35702 ext4: fix slab-use-after-free in ext4_split_extent_at()
We hit the following use-after-free:

==================================================================
BUG: KASAN: slab-use-after-free in ext4_split_extent_at+0xba8/0xcc0
Read of size 2 at addr ffff88810548ed08 by task kworker/u20:0/40
CPU: 0 PID: 40 Comm: kworker/u20:0 Not tainted 6.9.0-dirty #724
Call Trace:
 <TASK>
 kasan_report+0x93/0xc0
 ext4_split_extent_at+0xba8/0xcc0
 ext4_split_extent.isra.0+0x18f/0x500
 ext4_split_convert_extents+0x275/0x750
 ext4_ext_handle_unwritten_extents+0x73e/0x1580
 ext4_ext_map_blocks+0xe20/0x2dc0
 ext4_map_blocks+0x724/0x1700
 ext4_do_writepages+0x12d6/0x2a70
[...]

Allocated by task 40:
 __kmalloc_noprof+0x1ac/0x480
 ext4_find_extent+0xf3b/0x1e70
 ext4_ext_map_blocks+0x188/0x2dc0
 ext4_map_blocks+0x724/0x1700
 ext4_do_writepages+0x12d6/0x2a70
[...]

Freed by task 40:
 kfree+0xf1/0x2b0
 ext4_find_extent+0xa71/0x1e70
 ext4_ext_insert_extent+0xa22/0x3260
 ext4_split_extent_at+0x3ef/0xcc0
 ext4_split_extent.isra.0+0x18f/0x500
 ext4_split_convert_extents+0x275/0x750
 ext4_ext_handle_unwritten_extents+0x73e/0x1580
 ext4_ext_map_blocks+0xe20/0x2dc0
 ext4_map_blocks+0x724/0x1700
 ext4_do_writepages+0x12d6/0x2a70
[...]
==================================================================

The flow of issue triggering is as follows:

ext4_split_extent_at
  path = *ppath
  ext4_ext_insert_extent(ppath)
    ext4_ext_create_new_leaf(ppath)
      ext4_find_extent(orig_path)
        path = *orig_path
        read_extent_tree_block
          // return -ENOMEM or -EIO
        ext4_free_ext_path(path)
          kfree(path)
        *orig_path = NULL
  a. If err is -ENOMEM:
  ext4_ext_dirty(path + path->p_depth)
  // path use-after-free !!!
  b. If err is -EIO and we have EXT_DEBUG defined:
  ext4_ext_show_leaf(path)
    eh = path[depth].p_hdr
    // path also use-after-free !!!

So when trying to zeroout or fix the extent length, call ext4_find_extent()
to update the path.

In addition we use *ppath directly as an ext4_ext_show_leaf() input to
avoid possible use-after-free when EXT_DEBUG is defined, and to avoid
unnecessary path updates.

Fixes: dfe5080939 ("ext4: drop EXT4_EX_NOFREE_ON_ERR from rest of extents handling code")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-4-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:16 -04:00
Baokun Li
3e8a584c82 ext4: prevent partial update of the extents path
In ext4_ext_rm_idx() and ext4_ext_correct_indexes(), there is no proper
rollback of already executed updates when updating a level of the extents
path fails, so we may get an inconsistent extents tree, which may trigger
some bad things in errors=continue mode.

Hence clear the verified bit of modified extents buffers if the tree fails
to be updated in ext4_ext_rm_idx() or ext4_ext_correct_indexes(), which
forces the extents buffers to be checked in ext4_valid_extent_entries(),
ensuring that the extents tree is consistent.

Signed-off-by: zhanchengbin <zhanchengbin1@huawei.com>
Link: https://lore.kernel.org/r/20230213080514.535568-3-zhanchengbin1@huawei.com/
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-3-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:16 -04:00
Baokun Li
edfa71dbe8 ext4: refactor ext4_ext_rm_idx() to index 'path'
As suggested by Honza in Link,modify ext4_ext_rm_idx() to leave 'path'
alone and just index it like ext4_ext_correct_indexes() does it. This
facilitates adding error handling later. No functional changes.

Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/all/20230216130305.nrbtd42tppxhbynn@quack3/
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20240822023545.1994557-2-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-03 22:12:16 -04:00
Zhang Yi
c543e24296 ext4: update delalloc data reserve spcae in ext4_es_insert_extent()
Now that we update data reserved space for delalloc after allocating
new blocks in ext4_{ind|ext}_map_blocks(), and if bigalloc feature is
enabled, we also need to query the extents_status tree to calculate the
exact reserved clusters. This is complicated now and it appears that
it's better to do this job in ext4_es_insert_extent(), because
__es_remove_extent() have already count delalloc blocks when removing
delalloc extents and __revise_pending() return new adding pending count,
we could update the reserved blocks easily in ext4_es_insert_extent().

We direct reduce the reserved cluster count when replacing a delalloc
extent. However, thers are two special cases need to concern about the
quota claiming when doing direct block allocation (e.g. from fallocate).

A),
fallocate a range that covers a delalloc extent but start with
non-delayed allocated blocks, e.g. a hole.

  hhhhhhh+ddddddd+ddddddd
  ^^^^^^^^^^^^^^^^^^^^^^^  fallocate this range

Current ext4_map_blocks() can't always trim the extent since it may
release i_data_sem before calling ext4_map_create_blocks() and raced by
another delayed allocation. Hence the EXT4_GET_BLOCKS_DELALLOC_RESERVE
may not set even when we are replacing a delalloc extent, without this
flag set, the quota has already been claimed by ext4_mb_new_blocks(), so
we should release the quota reservations instead of claim them again.

B),
bigalloc feature is enabled, fallocate a range that contains non-delayed
allocated blocks.

  |<         one cluster       >|
  hhhhhhh+hhhhhhh+hhhhhhh+ddddddd
  ^^^^^^^  fallocate this range

This case is similar to above case, the EXT4_GET_BLOCKS_DELALLOC_RESERVE
flag is also not set.

Hence we should release the quota reservations if we replace a delalloc
extent but without EXT4_GET_BLOCKS_DELALLOC_RESERVE set.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20240813123452.2824659-7-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-02 15:26:14 -04:00
Zhang Yi
f3baf33b9c ext4: passing block allocation information to ext4_es_insert_extent()
Just pass the block allocation flag to ext4_es_insert_extent() when we
replacing a current extent after an actually block allocation or extent
status conversion, this flag will be used by later changes.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20240813123452.2824659-6-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-02 15:26:14 -04:00
Baokun Li
261341a932 ext4: set the type of max_zeroout to unsigned int to avoid overflow
The max_zeroout is of type int and the s_extent_max_zeroout_kb is of
type uint, and the s_extent_max_zeroout_kb can be freely modified via
the sysfs interface. When the block size is 1024, max_zeroout may
overflow, so declare it as unsigned int to avoid overflow.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240319113325.3110393-9-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-05-02 23:48:31 -04:00
Cheng Nie
547e64bda9 ext4: fix the comment of ext4_map_blocks()/ext4_ext_map_blocks()
this comment of ext4_map_blocks()/ext4_ext_map_blocks() need
update after commit c21770573319("ext4: Define a new set of
flags for ext4_get_blocks()").

Signed-off-by: Cheng Nie <niecheng1@uniontech.com>
Link: https://lore.kernel.org/r/20240118062511.28276-1-niecheng1@uniontech.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-02-21 22:33:21 -05:00
Zhang Yi
874eaba96d ext4: make ext4_map_blocks() distinguish delalloc only extent
Add a new map flag EXT4_MAP_DELAYED to indicate the mapping range is a
delayed allocated only (not unwritten) one, and making
ext4_map_blocks() can distinguish it, no longer mixing it with holes.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240127015825.1608160-6-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-02-01 23:59:21 -05:00
Zhang Yi
6430dea07e ext4: correct the hole length returned by ext4_map_blocks()
In ext4_map_blocks(), if we can't find a range of mapping in the
extents cache, we are calling ext4_ext_map_blocks() to search the real
path and ext4_ext_determine_hole() to determine the hole range. But if
the querying range was partially or completely overlaped by a delalloc
extent, we can't find it in the real extent path, so the returned hole
length could be incorrect.

Fortunately, ext4_ext_put_gap_in_cache() have already handle delalloc
extent, but it searches start from the expanded hole_start, doesn't
start from the querying range, so the delalloc extent found could not be
the one that overlaped the querying range, plus, it also didn't adjust
the hole length. Let's just remove ext4_ext_put_gap_in_cache(), handle
delalloc and insert adjusted hole extent in ext4_ext_determine_hole().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240127015825.1608160-4-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-02-01 23:47:02 -05:00
Kemeng Shi
2ffd2a6ad1 ext4: remove unnecessary parameter "needed" in ext4_discard_preallocations
The "needed" controls the number of ext4_prealloc_space to discard in
ext4_discard_preallocations. Function ext4_discard_preallocations is
supposed to discard all non-used preallocated blocks when "needed"
is 0 and now ext4_discard_preallocations is always called with "needed"
= 0. Remove unnecessary parameter "needed" and remove all non-used
preallocated spaces in ext4_discard_preallocations to simplify the
code.

Note: If count of non-used preallocated spaces could be more than
UINT_MAX, there was a memory leak as some non-used preallocated
spaces are left ununsed and this commit will fix it. Otherwise,
there is no behavior change.

Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240105092102.496631-9-shikemeng@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-01-18 10:52:45 -05:00
Ojaswin Mujoo
9257336914 ext4: treat end of range as exclusive in ext4_zero_range()
The call to filemap_write_and_wait_range() assumes the range passed to be
inclusive, so fix the call to make sure we follow that.

Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/e503107a7c73a2b68dec645c5ad798c437717c45.1698856309.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-01-04 23:28:47 -05:00
Linus Torvalds
57aff99745 Cleanup ext4's multi-block allocator, including adding some unit
tests, as well as cleaning how we update the backup superblock after
 online resizes or updating the label or uuid.
 
 Optimize handling of released data blocks in ext4's commit machinery
 to avoid a potential lock contention on s_md_lock spinlock.
 
 Fix a number of ext4 bugs:
 
  - fix race between writepages and remount
  - fix racy may inline data check in dio write
  - add missed brelse in an error path in update_backups
  - fix umask handling when ACL support is disabled
  - fix lost EIO error when a journal commit races with a fsync of the
    blockdev
  - fix potential improper i_size when there is a crash right after an
    O_SYNC direct  write.
  - check extent node for validity before potentially using what might
    be an invalid pointer
  - fix potential stale data exposure when writing to an unwritten extent
    and the file system is nearly out of space
  - fix potential accounting error around block reservations when writing
    partial delayed allocation writes to a bigalloc cluster
  - avoid memory allocation failure when tracking partial delayed allocation
    writes to a bigalloc cluster
  - fix various debugging print messages
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Merge tag 'ext4_for_linus-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Cleanup ext4's multi-block allocator, including adding some unit
  tests, as well as cleaning how we update the backup superblock after
  online resizes or updating the label or uuid.

  Optimize handling of released data blocks in ext4's commit machinery
  to avoid a potential lock contention on s_md_lock spinlock.

  Fix a number of ext4 bugs:

   - fix race between writepages and remount

   - fix racy may inline data check in dio write

   - add missed brelse in an error path in update_backups

   - fix umask handling when ACL support is disabled

   - fix lost EIO error when a journal commit races with a fsync of the
     blockdev

   - fix potential improper i_size when there is a crash right after an
     O_SYNC direct write.

   - check extent node for validity before potentially using what might
     be an invalid pointer

   - fix potential stale data exposure when writing to an unwritten
     extent and the file system is nearly out of space

   - fix potential accounting error around block reservations when
     writing partial delayed allocation writes to a bigalloc cluster

   - avoid memory allocation failure when tracking partial delayed
     allocation writes to a bigalloc cluster

   - fix various debugging print messages"

* tag 'ext4_for_linus-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (41 commits)
  ext4: properly sync file size update after O_SYNC direct IO
  ext4: fix racy may inline data check in dio write
  ext4: run mballoc test with different layouts setting
  ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc
  ext4: add some kunit stub for mballoc kunit test
  ext4: call ext4_mb_mark_context in ext4_group_add_blocks()
  ext4: Separate block bitmap and buddy bitmap freeing in ext4_group_add_blocks()
  ext4: call ext4_mb_mark_context in ext4_mb_clear_bb
  ext4: Separate block bitmap and buddy bitmap freeing in ext4_mb_clear_bb()
  ext4: call ext4_mb_mark_context in ext4_mb_mark_diskspace_used
  ext4: extend ext4_mb_mark_context to support allocation under journal
  ext4: call ext4_mb_mark_context in ext4_free_blocks_simple
  ext4: factor out codes to update block bitmap and group descriptor on disk from ext4_mb_mark_bb
  ext4: make state in ext4_mb_mark_bb to be bool
  jbd2: fix potential data lost in recovering journal raced with synchronizing fs bdev
  ext4: apply umask if ACL support is disabled
  ext4: mark buffer new if it is unwritten to avoid stale data exposure
  ext4: move 'ix' sanity check to corrent position
  jbd2: fix printk format type for 'io_block' in do_one_pass()
  jbd2: print io_block if check data block checksum failed when do recovery
  ...
2023-11-02 07:45:14 -10:00
Jeff Layton
b898ab2336
ext4: convert to new timestamp accessors
Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-33-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-18 13:26:21 +02:00
Kemeng Shi
d2f7cf40ea ext4: make state in ext4_mb_mark_bb to be bool
As state could only be either 0 or 1, just make it bool.

Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20230928160407.142069-2-shikemeng@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-10-05 22:32:15 -04:00
Gou Hao
af90a8f4a0 ext4: move 'ix' sanity check to corrent position
Check 'ix' before it is used.

Fixes: 80e675f906 ("ext4: optimize memmmove lengths in extent/index insertions")
Signed-off-by: Gou Hao <gouhao@uniontech.com>
Link: https://lore.kernel.org/r/20230906013341.7199-1-gouhao@uniontech.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-10-05 22:32:15 -04:00
Jeff Layton
1bc33893e7 ext4: convert to ctime accessor functions
In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-40-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-24 10:29:54 +02:00
Baokun Li
ab8627e104 ext4: make ext4_zeroout_es() return void
After ext4_es_insert_extent() returns void, the return value in
ext4_zeroout_es() is also unnecessary, so make it return void too.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230424033846.4732-13-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-06-26 19:35:12 -04:00
Baokun Li
6c120399cd ext4: make ext4_es_insert_extent() return void
Now ext4_es_insert_extent() never return error, so make it return void.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230424033846.4732-12-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-06-26 19:35:12 -04:00
Baokun Li
ed5d285b3f ext4: make ext4_es_remove_extent() return void
Now ext4_es_remove_extent() never fails, so make it return void.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230424033846.4732-10-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-06-26 19:35:12 -04:00
Ye Bin
835659598c ext4: fix use-after-free read in ext4_find_extent for bigalloc + inline
Syzbot found the following issue:
loop0: detected capacity change from 0 to 2048
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 without journal. Quota mode: none.
==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch_idx fs/ext4/extents.c:768 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0x76e/0xd90 fs/ext4/extents.c:931
Read of size 4 at addr ffff888073644750 by task syz-executor420/5067

CPU: 0 PID: 5067 Comm: syz-executor420 Not tainted 6.2.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x290 lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:306
 print_report+0x107/0x1f0 mm/kasan/report.c:417
 kasan_report+0xcd/0x100 mm/kasan/report.c:517
 ext4_ext_binsearch_idx fs/ext4/extents.c:768 [inline]
 ext4_find_extent+0x76e/0xd90 fs/ext4/extents.c:931
 ext4_clu_mapped+0x117/0x970 fs/ext4/extents.c:5809
 ext4_insert_delayed_block fs/ext4/inode.c:1696 [inline]
 ext4_da_map_blocks fs/ext4/inode.c:1806 [inline]
 ext4_da_get_block_prep+0x9e8/0x13c0 fs/ext4/inode.c:1870
 ext4_block_write_begin+0x6a8/0x2290 fs/ext4/inode.c:1098
 ext4_da_write_begin+0x539/0x760 fs/ext4/inode.c:3082
 generic_perform_write+0x2e4/0x5e0 mm/filemap.c:3772
 ext4_buffered_write_iter+0x122/0x3a0 fs/ext4/file.c:285
 ext4_file_write_iter+0x1d0/0x18f0
 call_write_iter include/linux/fs.h:2186 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7dc/0xc50 fs/read_write.c:584
 ksys_write+0x177/0x2a0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4b7a9737b9
RSP: 002b:00007ffc5cac3668 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4b7a9737b9
RDX: 00000000175d9003 RSI: 0000000020000200 RDI: 0000000000000004
RBP: 00007f4b7a933050 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000079f R11: 0000000000000246 R12: 00007f4b7a9330e0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Above issue is happens when enable bigalloc and inline data feature. As
commit 131294c35e fixed delayed allocation bug in ext4_clu_mapped for
bigalloc + inline. But it only resolved issue when has inline data, if
inline data has been converted to extent(ext4_da_convert_inline_data_to_extent)
before writepages, there is no EXT4_STATE_MAY_INLINE_DATA flag. However
i_data is still store inline data in this scene. Then will trigger UAF
when find extent.
To resolve above issue, there is need to add judge "ext4_has_inline_data(inode)"
in ext4_clu_mapped().

Fixes: 131294c35e ("ext4: fix delayed allocation bug in ext4_clu_mapped for bigalloc + inline")
Reported-by: syzbot+bf4bb7731ef73b83a3b4@syzkaller.appspotmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Tested-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20230406111627.1916759-1-tudor.ambarus@linaro.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-04-28 12:56:35 -04:00
Jan Kara
783ae448b7 ext4: Fix special handling of journalled data from extent zeroing
The handling of journalled data in ext4_zero_range() is incomplete. We
do not need to commit running transaction but we rather need to
checkpoint pages with journalled data. If we don't, journal tail can be
advanced beyond transaction containing the journalled data and if we
then crash before committing the transaction doing the zeroing we will
have inconsistent (too old) data in the file. Make sure file pages with
journalled data are properly checkpointed before removing them from the
page cache.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230329154950.19720-8-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-04-14 19:56:53 -04:00
Jan Kara
c000dfec7e ext4: Drop special handling of journalled data from extent shifting operations
Now that filemap_write_and_wait() makes sure pages with journalled data
are safely on disk, ext4_collapse_range() and ext4_insert_range() do
not need special handling of journalled data.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230329154950.19720-7-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-04-14 19:56:53 -04:00
zhanchengbin
3f5424790d ext4: fix inode tree inconsistency caused by ENOMEM
If ENOMEM fails when the extent is splitting, we need to restore the length
of the split extent.
In the ext4_split_extent_at function, only in ext4_ext_create_new_leaf will
it alloc memory and change the shape of the extent tree,even if an ENOMEM
is returned at this time, the extent tree is still self-consistent, Just
restore the split extent lens in the function ext4_split_extent_at.

ext4_split_extent_at
 ext4_ext_insert_extent
  ext4_ext_create_new_leaf
   1)ext4_ext_split
     ext4_find_extent
   2)ext4_ext_grow_indepth
     ext4_find_extent

Signed-off-by: zhanchengbin <zhanchengbin1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230103022812.130603-1-zhanchengbin1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-02-18 23:58:28 -05:00
Eric Whitney
131294c35e ext4: fix delayed allocation bug in ext4_clu_mapped for bigalloc + inline
When converting files with inline data to extents, delayed allocations
made on a file system created with both the bigalloc and inline options
can result in invalid extent status cache content, incorrect reserved
cluster counts, kernel memory leaks, and potential kernel panics.

With bigalloc, the code that determines whether a block must be
delayed allocated searches the extent tree to see if that block maps
to a previously allocated cluster.  If not, the block is delayed
allocated, and otherwise, it isn't.  However, if the inline option is
also used, and if the file containing the block is marked as able to
store data inline, there isn't a valid extent tree associated with
the file.  The current code in ext4_clu_mapped() calls
ext4_find_extent() to search the non-existent tree for a previously
allocated cluster anyway, which typically finds nothing, as desired.
However, a side effect of the search can be to cache invalid content
from the non-existent tree (garbage) in the extent status tree,
including bogus entries in the pending reservation tree.

To fix this, avoid searching the extent tree when allocating blocks
for bigalloc + inline files that are being converted from inline to
extent mapped.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20221117152207.2424-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2022-12-08 21:49:25 -05:00
Jiangshan Yi
66267814ba fs/ext4: replace ternary operator with min()/max() and min_t()
Fix the following coccicheck warning:

fs/ext4/inline.c:183: WARNING opportunity for min().
fs/ext4/extents.c:2631: WARNING opportunity for max().
fs/ext4/extents.c:2632: WARNING opportunity for min().
fs/ext4/extents.c:5559: WARNING opportunity for max().
fs/ext4/super.c:6908: WARNING opportunity for min().

min()/max() and min_t() macro is defined in include/linux/minmax.h.
It avoids multiple evaluations of the arguments when non-constant and
performs strict type-checking.

Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jiangshan Yi <yijiangshan@kylinos.cn>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Link: https://lore.kernel.org/r/20220817025928.612851-1-13667453960@163.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-11-29 16:10:49 -05:00
Baokun Li
f6b1a1cf1c ext4: fix use-after-free in ext4_ext_shift_extents
If the starting position of our insert range happens to be in the hole
between the two ext4_extent_idx, because the lblk of the ext4_extent in
the previous ext4_extent_idx is always less than the start, which leads
to the "extent" variable access across the boundary, the following UAF is
triggered:
==================================================================
BUG: KASAN: use-after-free in ext4_ext_shift_extents+0x257/0x790
Read of size 4 at addr ffff88819807a008 by task fallocate/8010
CPU: 3 PID: 8010 Comm: fallocate Tainted: G            E     5.10.0+ #492
Call Trace:
 dump_stack+0x7d/0xa3
 print_address_description.constprop.0+0x1e/0x220
 kasan_report.cold+0x67/0x7f
 ext4_ext_shift_extents+0x257/0x790
 ext4_insert_range+0x5b6/0x700
 ext4_fallocate+0x39e/0x3d0
 vfs_fallocate+0x26f/0x470
 ksys_fallocate+0x3a/0x70
 __x64_sys_fallocate+0x4f/0x60
 do_syscall_64+0x33/0x40
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
==================================================================

For right shifts, we can divide them into the following situations:

1. When the first ee_block of ext4_extent_idx is greater than or equal to
   start, make right shifts directly from the first ee_block.
    1) If it is greater than start, we need to continue searching in the
       previous ext4_extent_idx.
    2) If it is equal to start, we can exit the loop (iterator=NULL).

2. When the first ee_block of ext4_extent_idx is less than start, then
   traverse from the last extent to find the first extent whose ee_block
   is less than start.
    1) If extent is still the last extent after traversal, it means that
       the last ee_block of ext4_extent_idx is less than start, that is,
       start is located in the hole between idx and (idx+1), so we can
       exit the loop directly (break) without right shifts.
    2) Otherwise, make right shifts at the corresponding position of the
       found extent, and then exit the loop (iterator=NULL).

Fixes: 331573febb ("ext4: Add support FALLOC_FL_INSERT_RANGE for fallocate")
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20220922120434.1294789-1-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-11-07 12:53:43 -05:00
Ye Bin
7ff5fddadd ext4: factor out ext4_free_ext_path()
Factor out ext4_free_ext_path() to free extent path. As after previous patch
'ext4_ext_drop_refs()' is only used in 'extents.c', so make it static.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220924021211.3831551-3-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-09-30 23:46:54 -04:00
Luís Henriques
29a5b8a137 ext4: fix bug in extents parsing when eh_entries == 0 and eh_depth > 0
When walking through an inode extents, the ext4_ext_binsearch_idx() function
assumes that the extent header has been previously validated.  However, there
are no checks that verify that the number of entries (eh->eh_entries) is
non-zero when depth is > 0.  And this will lead to problems because the
EXT_FIRST_INDEX() and EXT_LAST_INDEX() will return garbage and result in this:

[  135.245946] ------------[ cut here ]------------
[  135.247579] kernel BUG at fs/ext4/extents.c:2258!
[  135.249045] invalid opcode: 0000 [#1] PREEMPT SMP
[  135.250320] CPU: 2 PID: 238 Comm: tmp118 Not tainted 5.19.0-rc8+ #4
[  135.252067] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014
[  135.255065] RIP: 0010:ext4_ext_map_blocks+0xc20/0xcb0
[  135.256475] Code:
[  135.261433] RSP: 0018:ffffc900005939f8 EFLAGS: 00010246
[  135.262847] RAX: 0000000000000024 RBX: ffffc90000593b70 RCX: 0000000000000023
[  135.264765] RDX: ffff8880038e5f10 RSI: 0000000000000003 RDI: ffff8880046e922c
[  135.266670] RBP: ffff8880046e9348 R08: 0000000000000001 R09: ffff888002ca580c
[  135.268576] R10: 0000000000002602 R11: 0000000000000000 R12: 0000000000000024
[  135.270477] R13: 0000000000000000 R14: 0000000000000024 R15: 0000000000000000
[  135.272394] FS:  00007fdabdc56740(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000
[  135.274510] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  135.276075] CR2: 00007ffc26bd4f00 CR3: 0000000006261004 CR4: 0000000000170ea0
[  135.277952] Call Trace:
[  135.278635]  <TASK>
[  135.279247]  ? preempt_count_add+0x6d/0xa0
[  135.280358]  ? percpu_counter_add_batch+0x55/0xb0
[  135.281612]  ? _raw_read_unlock+0x18/0x30
[  135.282704]  ext4_map_blocks+0x294/0x5a0
[  135.283745]  ? xa_load+0x6f/0xa0
[  135.284562]  ext4_mpage_readpages+0x3d6/0x770
[  135.285646]  read_pages+0x67/0x1d0
[  135.286492]  ? folio_add_lru+0x51/0x80
[  135.287441]  page_cache_ra_unbounded+0x124/0x170
[  135.288510]  filemap_get_pages+0x23d/0x5a0
[  135.289457]  ? path_openat+0xa72/0xdd0
[  135.290332]  filemap_read+0xbf/0x300
[  135.291158]  ? _raw_spin_lock_irqsave+0x17/0x40
[  135.292192]  new_sync_read+0x103/0x170
[  135.293014]  vfs_read+0x15d/0x180
[  135.293745]  ksys_read+0xa1/0xe0
[  135.294461]  do_syscall_64+0x3c/0x80
[  135.295284]  entry_SYSCALL_64_after_hwframe+0x46/0xb0

This patch simply adds an extra check in __ext4_ext_check(), verifying that
eh_entries is not 0 when eh_depth is > 0.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215941
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216283
Cc: Baokun Li <libaokun1@huawei.com>
Cc: stable@kernel.org
Signed-off-by: Luís Henriques <lhenriques@suse.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20220822094235.2690-1-lhenriques@suse.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-09-22 10:50:54 -04:00