spi: Fix use-after-free with devm_spi_alloc_* (Linux Linux)

CVE-2021-46959
HIGH 7.8

At a glance

Source
NVD
EPSS
EPSS 0.24 % · percentile 16 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: spi: Fix use-after-free with devm_spi_alloc_* We can't rely on the contents of the devres list during spi_unregister_controller(), as the list is already torn down at the time we perform devres_find() for devm_spi_release_controller. This causes devices registered with devm_spi_alloc_{master,slave}() to be mistakenly identified as legacy, non-devm managed devices and have their reference counters decremented below 0. ------------[ cut here ]------------ WARNING: CPU: 1 PID: 660 at lib/refcount.c:28 refcount_warn_saturate+0x108/0x174 [<b0396f04>] (refcount_warn_saturate) from [<b03c56a4>] (kobject_put+0x90/0x98) [<b03c5614>] (kobject_put) from [<b0447b4c>] (put_device+0x20/0x24) r4:b6700140 [<b0447b2c>] (put_device) from [<b07515e8>] (devm_spi_release_controller+0x3c/0x40) [<b07515ac>] (devm_spi_release_controller) from [<b045343c>] (release_nodes+0x84/0xc4) r5:b6700180 r4:b6700100 [<b04533b8>] (release_nodes) from [<b0454160>] (devres_release_all+0x5c/0x60) r8:b1638c54 r7:b117ad94 r6:b1638c10 r5:b117ad94 r4:b163dc10 [<b0454104>] (devres_release_all) from [<b044e41c>] (__device_release_driver+0x144/0x1ec) r5:b117ad94 r4:b163dc10 [<b044e2d8>] (__device_release_driver) from [<b044f70c>] (device_driver_detach+0x84/0xa0) r9:00000000 r8:00000000 r7:b117ad94 r6:b163dc54 r5:b1638c10 r4:b163dc10 [<b044f688>] (device_driver_detach) from [<b044d274>] (unbind_store+0xe4/0xf8) Instead, determine the devm allocation state as a flag on the controller which is guaranteed to be stable during cleanup.

Weaknesses (CWE)

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · nvd@nist.gov (Primary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected a4add022c1552b0d51a0b89a4781919d6ebac4f9 < 62bb2c7f2411a0045c24831f11ecacfc35610815 ; affected 0870525cf94bc27907e94ce99afb6d7239ffd2f5 < 8bf96425c90f5c1dcf3b7b9df568019a1d4b8a0e ; affected 8c45a1c6c951bbe7f95db78fcab46f7337364468 < 8e029707f50a82c53172359c686b2536ab54e58c ; affected 234b432c7b6184b2d6c5ba2c55f0dd5023c0edf0 < 28a5529068c51cdf0295ab1e11a99a3a909a03e4 ; affected 3e04a4976addbedcad326f47b0dd4efc570a1fac < 001c8e83646ad3b847b18f6ac55a54367d917d74 ; affected 5e844cc37a5cbaa460e68f9a989d321d63088a89 < c7fabe372a9031acd00498bc718ce27c253abfd1
Linux · Linuxaffected 5.10 ; unaffected 0 < 5.10 ; unaffected 4.4.271 ≤ 4.4.* ; unaffected 4.9.271 ≤ 4.9.* ; unaffected 4.14.233 ≤ 4.14.* ; unaffected 4.19.191 ≤ 4.19.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD