linux/fs/ext4
Alexey Khoroshilov 2c00ef3ee3 ext4: implement error handling of ext4_mb_new_preallocation()
If memory allocation in ext4_mb_new_group_pa() is failed,
it returns error code, ext4_mb_new_preallocation() propages it,
but ext4_mb_new_blocks() ignores it.

An observed result was:

- allocation fail means ext4_mb_new_group_pa() does not update
  ext4_allocation_context;

- ext4_mb_new_blocks() sets ext4_allocation_request->len (ar->len =
  ac->ac_b_ex.fe_len;) to number of blocks preallocated (512) instead
  of number of blocks requested (1);

- that activates update cycle in ext4_splice_branch():
    for (i = 1; i < blks; i++) <-- blks is 512 instead of 1 here
      *(where->p + i) = cpu_to_le32(current_block++);

- it iterates 511 times and corrupts a chunk of memory including inode
  structure;

- page fault happens at EXT4_SB(inode->i_sb) in ext4_mark_inode_dirty();

- system hangs with 'scheduling while atomic' BUG.

The patch implements a check for ext4_mb_new_preallocation() error
code and handles its failure as if ext4_mb_regular_allocator() fails.

Found by Linux File System Verification project (linuxtesting.org).

[ Patch restructed by tytso to make the flow of control easier to follow. ]

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-07-01 08:12:36 -04:00
..
acl.c ext4: fix the number of credits needed for acl ops with inline data 2013-02-09 15:23:03 -05:00
acl.h fs: take the ACL checks to common code 2011-07-25 14:30:23 -04:00
balloc.c ext4: optimize test_root() 2013-06-06 11:40:37 -04:00
bitmap.c ext4: Checksum the block bitmap properly with bigalloc enabled 2012-10-22 00:34:32 -04:00
block_validity.c ext2/3/4: delete unneeded includes of module.h 2012-01-09 13:52:10 +01:00
dir.c ext4: fix readdir error in the case of inline_data+dir_index 2013-04-19 17:53:09 -04:00
ext4_extents.h ext4: mext_insert_extents should update extent block checksum 2013-04-19 14:04:12 -04:00
ext4_jbd2.c ext4: provide wrappers for transaction reservation calls 2013-06-04 12:37:50 -04:00
ext4_jbd2.h ext4: use transaction reservation for extent conversion in ext4_end_io 2013-06-04 13:21:11 -04:00
ext4.h ext4: add sanity check to ext4_get_group_info() 2013-06-06 11:16:43 -04:00
extents_status.c ext4: fix fio regression 2013-05-03 02:15:52 -04:00
extents_status.h ext4: fix fio regression 2013-05-03 02:15:52 -04:00
extents.c ext4: return FIEMAP_EXTENT_UNKNOWN for delalloc extents 2013-06-12 23:13:59 -04:00
file.c ext4: fix overflows in SEEK_HOLE, SEEK_DATA implementations 2013-05-31 19:37:56 -04:00
fsync.c ext4: Fix fsync error handling after filesystem abort 2013-06-12 22:38:04 -04:00
hash.c ext4: reduce one "if" comparison in ext4_dirhash() 2013-02-01 22:33:21 -05:00
ialloc.c ext4: provide wrappers for transaction reservation calls 2013-06-04 12:37:50 -04:00
indirect.c ext4: don't use EXT4_FREE_BLOCKS_FORGET unnecessarily 2013-06-12 11:48:29 -04:00
inline.c ext4: fix data offset overflow on 32-bit archs in ext4_inline_data_fiemap() 2013-05-31 19:33:42 -04:00
inode.c ext4: use ext4_da_writepages() for all modes 2013-06-06 14:00:46 -04:00
ioctl.c ext4: fix usless declarations 2013-04-09 22:48:36 -04:00
Kconfig ext4: fix Kconfig documentation for CONFIG_EXT4_DEBUG 2013-04-21 20:32:03 -04:00
Makefile ext4: Remove CONFIG_EXT4_FS_XATTR 2012-12-10 16:30:43 -05:00
mballoc.c ext4: implement error handling of ext4_mb_new_preallocation() 2013-07-01 08:12:36 -04:00
mballoc.h ext4: use module parameters instead of debugfs for mballoc_debug 2013-02-09 16:28:20 -05:00
migrate.c ext4: do not convert to indirect with bigalloc enabled 2013-04-11 10:54:46 -04:00
mmp.c ext4: mark all metadata I/O with REQ_META 2013-04-20 15:46:17 -04:00
move_extent.c ext4: delete unused variables 2013-06-17 08:56:26 -04:00
namei.c ext4: fix readdir error in the case of inline_data+dir_index 2013-04-19 17:53:09 -04:00
page-io.c ext4: add check to io_submit_init_bio 2013-06-06 10:18:22 -04:00
resize.c ext4: fix corruption when online resizing a fs with 1K block size 2013-07-01 08:12:08 -04:00
super.c ext4: delete unused variables 2013-06-17 08:56:26 -04:00
symlink.c ext4: Remove CONFIG_EXT4_FS_XATTR 2012-12-10 16:30:43 -05:00
truncate.h ext4: move common truncate functions to header file 2011-06-27 19:16:04 -04:00
xattr_security.c Merge branch 'for_linus' into for_linus_merged 2012-01-10 11:54:07 -05:00
xattr_trusted.c ext2/3/4: delete unneeded includes of module.h 2012-01-09 13:52:10 +01:00
xattr_user.c ext2/3/4: delete unneeded includes of module.h 2012-01-09 13:52:10 +01:00
xattr.c ext4: fix miscellaneous big endian warnings 2013-04-09 23:59:55 -04:00
xattr.h ext4: reserve xattr index for Rich ACL support 2013-04-18 14:53:15 -04:00