CVE-2023-52813

Summary

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

crypto: pcrypt - Fix hungtask for PADATA_RESET

We found a hungtask bug in test_aead_vec_cfg as follows:

INFO: task cryptomgr_test:391009 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Call trace: __switch_to+0x98/0xe0 __schedule+0x6c4/0xf40 schedule+0xd8/0x1b4 schedule_timeout+0x474/0x560 wait_for_common+0x368/0x4e0 wait_for_completion+0x20/0x30 wait_for_completion+0x20/0x30 test_aead_vec_cfg+0xab4/0xd50 test_aead+0x144/0x1f0 alg_test_aead+0xd8/0x1e0 alg_test+0x634/0x890 cryptomgr_test+0x40/0x70 kthread+0x1e0/0x220 ret_from_fork+0x10/0x18 Kernel panic - not syncing: hung_task: blocked tasks

For padata_do_parallel, when the return err is 0 or -EBUSY, it will call wait_for_completion(&wait->completion) in test_aead_vec_cfg. In normal case, aead_request_complete() will be called in pcrypt_aead_serial and the return err is 0 for padata_do_parallel. But, when pinst->flags is PADATA_RESET, the return err is -EBUSY for padata_do_parallel, and it won't call aead_request_complete(). Therefore, test_aead_vec_cfg will hung at wait_for_completion(&wait->completion), which will cause hungtask.

The problem comes as following: (padata_do_parallel) | rcu_read_lock_bh(); | err = -EINVAL; | (padata_replace) | pinst->flags |= PADATA_RESET; err = -EBUSY | if (pinst->flags & PADATA_RESET) | rcu_read_unlock_bh() | return err

In order to resolve the problem, we replace the return err -EBUSY with -EAGAIN, which means parallel_data is changing, and the caller should call it again.

v3: remove retry and just change the return err. v2: introduce padata_try_do_parallel() in pcrypt_aead_encrypt and pcrypt_aead_decrypt to solve the hungtask.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < fb2d3a50a8f29a3c66682bb426144f40e32ab818affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < 039fec48e062504f14845124a1a25eb199b2ddc0affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < c9c1334697301c10e6918d747ed38abfbc0c96e7affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < e97bf4ada7dddacd184c3e196bd063b0dc71b41daffected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < 546c1796ad1ed0d87dab3c4b5156d75819be2316affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < c55fc098fd9d2dca475b82d00ffbcaf97879d77eaffected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < e134f3aba98e6c801a693f540912c2d493718ddfaffected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < 372636debe852913529b1716f44addd94fff2d28affected
LinuxLinux16295bec6398a3eedc9377e1af6ff4c71b98c300 < 8f4f68e788c3a7a696546291258bfa5fdb215523affected
LinuxLinux2.6.34affected
LinuxLinux0 < 2.6.34unaffected
LinuxLinux4.14.331 <= 4.14.*unaffected
LinuxLinux4.19.300 <= 4.19.*unaffected
LinuxLinux5.4.262 <= 5.4.*unaffected
LinuxLinux5.10.202 <= 5.10.*unaffected
LinuxLinux5.15.140 <= 5.15.*unaffected
LinuxLinux6.1.64 <= 6.1.*unaffected
LinuxLinux6.5.13 <= 6.5.*unaffected
LinuxLinux6.6.3 <= 6.6.*unaffected
LinuxLinux6.7 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

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

CVE Program Container

Additional References

References