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CVE PROGRAM SOURCE RECORD7.8 High

CVE-2024-57929

dm array: fix releasing a faulty array block twice in dm_array_cursor_end

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Status
Published
Published
Updated
Assigning organization
Linux

Description

In the Linux kernel, the following vulnerability has been resolved: dm array: fix releasing a faulty array block twice in dm_array_cursor_end When dm_bm_read_lock() fails due to locking or checksum errors, it releases the faulty block implicitly while leaving an invalid output pointer behind. The caller of dm_bm_read_lock() should not operate on this invalid dm_block pointer, or it will lead to undefined result. For example, the dm_array_cursor incorrectly caches the invalid pointer on reading a faulty array block, causing a double release in dm_array_cursor_end(), then hitting the BUG_ON in dm-bufio cache_put(). Reproduce steps: 1. initialize a cache device dmsetup create cmeta --table "0 8192 linear /dev/sdc 0" dmsetup create cdata --table "0 65536 linear /dev/sdc 8192" dmsetup create corig --table "0 524288 linear /dev/sdc $262144" dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0" 2. wipe the second array block offline dmsteup remove cache cmeta cdata corig mapping_root=$(dd if=/dev/sdc bs=1c count=8 skip=192 \ 2>/dev/null | hexdump -e '1/8 "%u\n"') ablock=$(dd if=/dev/sdc bs=1c count=8 skip=$((4096*mapping_root+2056)) \ 2>/dev/null | hexdump -e '1/8 "%u\n"') dd if=/dev/zero of=/dev/sdc bs=4k count=1 seek=$ablock 3. try reopen the cache device dmsetup create cmeta --table "0 8192 linear /dev/sdc 0" dmsetup create cdata --table "0 65536 linear /dev/sdc 8192" dmsetup create corig --table "0 524288 linear /dev/sdc $262144" dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0" Kernel logs: (snip) device-mapper: array: array_block_check failed: blocknr 0 != wanted 10 device-mapper: block manager: array validator check failed for block 10 device-mapper: array: get_ablock failed device-mapper: cache metadata: dm_array_cursor_next for mapping failed ------------[ cut here ]------------ kernel BUG at drivers/md/dm-bufio.c:638! Fix by setting the cached block pointer to NULL on errors. In addition to the reproducer described above, this fix can be verified using the "array_cursor/damaged" test in dm-unit: dm-unit run /pdata/array_cursor/damaged --kernel-dir <KERNEL_DIR>

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • fdd1315aa5f022fe6574efdc2d9535f75a0ee255 to < 9c7c03d0e926762adf3a3a0ba86156fb5e19538baffected
  • fdd1315aa5f022fe6574efdc2d9535f75a0ee255 to < fc1ef07c3522e257e32702954f265debbcb096a7affected
  • fdd1315aa5f022fe6574efdc2d9535f75a0ee255 to < 738994872d77e189b2d13c501a1d145e95d98f46affected
  • fdd1315aa5f022fe6574efdc2d9535f75a0ee255 to < e477021d252c007f0c6d45b5d13d341efed03979affected
  • fdd1315aa5f022fe6574efdc2d9535f75a0ee255 to < 6002bec5354f86d1a2df21468f68e3ec03ede9daaffected
  • fdd1315aa5f022fe6574efdc2d9535f75a0ee255 to < 017c4470bff53585370028fec9341247bad358ffaffected
  • fdd1315aa5f022fe6574efdc2d9535f75a0ee255 to < f2893c0804d86230ffb8f1c8703fdbb18648abc8affected

Linux Linux

Default version status: affected

  • 4.9affected
  • 0 to < 4.9unaffected
  • 5.4.290 to ≤ 5.4.*unaffected
  • 5.10.234 to ≤ 5.10.*unaffected
  • 5.15.177 to ≤ 5.15.*unaffected
  • 6.1.125 to ≤ 6.1.*unaffected
  • 6.6.72 to ≤ 6.6.*unaffected
  • 6.12.10 to ≤ 6.12.*unaffected
  • 6.13 to ≤ *unaffected

References