CVE-2024-35844

Summary

In the Linux kernel, the following vulnerability has been resolved:

f2fs: compress: fix reserve_cblocks counting error when out of space

When a file only needs one direct_node, performing the following operations will cause the file to be unrepairable:

unisoc # ./f2fs_io compress test.apk unisoc #df -h | grep dm-48 /dev/block/dm-48 112G 112G 1.2M 100% /data

unisoc # ./f2fs_io release_cblocks test.apk 924 unisoc # df -h | grep dm-48 /dev/block/dm-48 112G 112G 4.8M 100% /data

unisoc # dd if=/dev/random of=file4 bs=1M count=3 3145728 bytes (3.0 M) copied, 0.025 s, 120 M/s unisoc # df -h | grep dm-48 /dev/block/dm-48 112G 112G 1.8M 100% /data

unisoc # ./f2fs_io reserve_cblocks test.apk F2FS_IOC_RESERVE_COMPRESS_BLOCKS failed: No space left on device

adb reboot unisoc # df -h | grep dm-48 /dev/block/dm-48 112G 112G 11M 100% /data unisoc # ./f2fs_io reserve_cblocks test.apk 0

This is because the file has only one direct_node. After returning to -ENOSPC, reserved_blocks += ret will not be executed. As a result, the reserved_blocks at this time is still 0, which is not the real number of reserved blocks. Therefore, fsck cannot be set to repair the file.

After this patch, the fsck flag will be set to fix this problem.

unisoc # df -h | grep dm-48 /dev/block/dm-48 112G 112G 1.8M 100% /data unisoc # ./f2fs_io reserve_cblocks test.apk F2FS_IOC_RESERVE_COMPRESS_BLOCKS failed: No space left on device

adb reboot then fsck will be executed unisoc # df -h | grep dm-48 /dev/block/dm-48 112G 112G 11M 100% /data unisoc # ./f2fs_io reserve_cblocks test.apk 924

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxc75488fb4d82b697f381f855bf5b16779df440aa < fa3ac8b1a227d9b470b87972494293348b5839eeaffected
LinuxLinuxc75488fb4d82b697f381f855bf5b16779df440aa < 889846dfc8ee2cf31148a44bfd2faeb2faadc685affected
LinuxLinuxc75488fb4d82b697f381f855bf5b16779df440aa < f0bf89e84c3afb79d7a3a9e4bc853ad6a3245c0aaffected
LinuxLinuxc75488fb4d82b697f381f855bf5b16779df440aa < 569c198c9e2093fd29cc071856a4e548fda506bcaffected
LinuxLinuxc75488fb4d82b697f381f855bf5b16779df440aa < fc0aed88afbf6f606205129a7466eebdf528e3f3affected
LinuxLinuxc75488fb4d82b697f381f855bf5b16779df440aa < 2f6d721e14b69d6e1251f69fa238b48e8374e25faffected
LinuxLinux5.8affected
LinuxLinux0 < 5.8unaffected
LinuxLinux5.15.153 <= 5.15.*unaffected
LinuxLinux6.1.83 <= 6.1.*unaffected
LinuxLinux6.6.23 <= 6.6.*unaffected
LinuxLinux6.7.11 <= 6.7.*unaffected
LinuxLinux6.8.2 <= 6.8.*unaffected
LinuxLinux6.9 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

References