u-boot/fs
Qu Wenruo 511a1303c9 fs: btrfs: limit the mapped length to the original length
[BUG]
There is a bug report that btrfs driver caused hang during file read:

  This breaks btrfs on the HiFive Unmatched.

  => pci enum
  PCIE-0: Link up (Gen1-x8, Bus0)
  => nvme scan
  => load nvme 0:2 0x8c000000 /boot/dtb/sifive/hifive-unmatched-a00.dtb
  [hangs]

[CAUSE]
The reporter provided some debug output:

  read_extent_data: cur=615817216, orig_len=16384, cur_len=16384
  read_extent_data: btrfs_map_block: cur_len=479944704; ret=0
  read_extent_data: ret=0
  read_extent_data: cur=615833600, orig_len=4096, cur_len=4096
  read_extent_data: btrfs_map_block: cur_len=479928320; ret=0

Note the second and the last line, the @cur_len is 450+MiB, which is
almost a chunk size.

And inside __btrfs_map_block(), we limits the returned value to stripe
length, but that's depending on the chunk type:

	if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
			 BTRFS_BLOCK_GROUP_RAID1C3 | BTRFS_BLOCK_GROUP_RAID1C4 |
			 BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 |
			 BTRFS_BLOCK_GROUP_RAID10 |
			 BTRFS_BLOCK_GROUP_DUP)) {
		/* we limit the length of each bio to what fits in a stripe */
		*length = min_t(u64, ce->size - offset,
			      map->stripe_len - stripe_offset);
	} else {
		*length = ce->size - offset;
	}

This means, if the chunk is SINGLE profile, then we don't limit the
returned length at all, and even for other profiles, we can still return
a length much larger than the requested one.

[FIX]
Properly clamp the returned length, preventing it from returning a much
larger range than expected.

Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Qu Wenruo <wqu@suse.com>
2023-02-23 13:29:19 -05:00
..
btrfs fs: btrfs: limit the mapped length to the original length 2023-02-23 13:29:19 -05:00
cbfs spl: Ensure all SPL symbols in Kconfig have some SPL dependency 2022-07-07 09:29:08 -04:00
cramfs cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
erofs Correct SPL use of FS_EROFS 2023-02-10 07:41:39 -05:00
ext4 fs: ext4: Fix free(NULL) 2022-12-08 09:28:31 -05:00
fat log: Add a category for filesystems 2023-02-06 13:04:53 -05:00
jffs2 fs: jffs2: Move SYS_JFFS2_SORT_FRAGMENTS to Kconfig 2022-11-10 09:45:54 -05:00
reiserfs common: Drop asm/global_data.h from common header 2021-02-02 15:33:42 -05:00
sandbox bootstd: sandbox: Add a hostfs bootdev 2022-04-25 10:00:04 -04:00
squashfs lib: zstd: update to latest Linux zstd 1.5.2 2023-01-18 19:04:17 -05:00
ubifs ubifs: Allow to silence debug dumps 2022-11-23 13:06:12 -05:00
yaffs2 fs: yaffs2: Finish Kconfig migration 2021-11-05 11:23:29 -04:00
zfs common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
fs.c common: Drop display_options.h from common header 2022-08-10 13:46:55 -04:00
fs_internal.c fs: Quieten down the filesystems more 2022-10-17 21:17:12 -06:00
Kconfig bootstd: sandbox: Add a hostfs bootdev 2022-04-25 10:00:04 -04:00
Makefile fs: Add semihosting filesystem 2022-04-01 15:03:13 -04:00
semihostingfs.c fs: Add semihosting filesystem 2022-04-01 15:03:13 -04:00