{"id":"CVE-2024-56755","summary":"netfs/fscache: Add a memory barrier for FSCACHE_VOLUME_CREATING","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs/fscache: Add a memory barrier for FSCACHE_VOLUME_CREATING\n\nIn fscache_create_volume(), there is a missing memory barrier between the\nbit-clearing operation and the wake-up operation. This may cause a\nsituation where, after a wake-up, the bit-clearing operation hasn't been\ndetected yet, leading to an indefinite wait. The triggering process is as\nfollows:\n\n  [cookie1]                [cookie2]                  [volume_work]\nfscache_perform_lookup\n  fscache_create_volume\n                        fscache_perform_lookup\n                          fscache_create_volume\n\t\t\t                        fscache_create_volume_work\n                                                  cachefiles_acquire_volume\n                                                  clear_and_wake_up_bit\n    test_and_set_bit\n                            test_and_set_bit\n                              goto maybe_wait\n      goto no_wait\n\nIn the above process, cookie1 and cookie2 has the same volume. When cookie1\nenters the -no_wait- process, it will clear the bit and wake up the waiting\nprocess. If a barrier is missing, it may cause cookie2 to remain in the\n-wait- process indefinitely.\n\nIn commit 3288666c7256 (\"fscache: Use clear_and_wake_up_bit() in\nfscache_create_volume_work()\"), barriers were added to similar operations\nin fscache_create_volume_work(), but fscache_create_volume() was missed.\n\nBy combining the clear and wake operations into clear_and_wake_up_bit() to\nfix this issue.","modified":"2026-04-02T12:25:13.560379Z","published":"2024-12-29T11:30:19.795Z","related":["SUSE-SU-2025:0117-1","SUSE-SU-2025:0153-1","SUSE-SU-2025:0154-1","SUSE-SU-2025:0201-1","SUSE-SU-2025:0201-2","SUSE-SU-2025:0229-1","SUSE-SU-2025:0289-1","SUSE-SU-2025:20165-1","SUSE-SU-2025:20166-1","SUSE-SU-2025:20248-1","SUSE-SU-2025:20249-1","USN-7276-1","USN-7277-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/56xxx/CVE-2024-56755.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/22f9400a6f3560629478e0a64247b8fcc811a24d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/539fabba965e119b98066fc6ba5257b5eaf4eda2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8beb682cc9a0798a280bbb95e3e41617237090b2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8cc1df3113cb71a0df2c46dd5b102c9e11c8a8c6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ddab02607eed9e415dc62fde421d4329e5345315"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/56xxx/CVE-2024-56755.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-56755"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"bfa22da3ed652aa15acd4246fa13a0de6dbe4a59"},{"fixed":"ddab02607eed9e415dc62fde421d4329e5345315"},{"fixed":"539fabba965e119b98066fc6ba5257b5eaf4eda2"},{"fixed":"8beb682cc9a0798a280bbb95e3e41617237090b2"},{"fixed":"8cc1df3113cb71a0df2c46dd5b102c9e11c8a8c6"},{"fixed":"22f9400a6f3560629478e0a64247b8fcc811a24d"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-56755.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}