{"id":"CVE-2022-49443","state":"PUBLISHED","title":"list: fix a data-race around ep->rdllist","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nlist: fix a data-race around ep->rdllist\n\nep_poll() first calls ep_events_available() with no lock held and checks\nif ep->rdllist is empty by list_empty_careful(), which reads\nrdllist->prev.  Thus all accesses to it need some protection to avoid\nstore/load-tearing.\n\nNote INIT_LIST_HEAD_RCU() already has the annotation for both prev\nand next.\n\nCommit bf3b9f6372c4 (\"epoll: Add busy poll support to epoll with socket\nfds.\") added the first lockless ep_events_available(), and commit\nc5a282e9635e (\"fs/epoll: reduce the scope of wq lock in epoll_wait()\")\nmade some ep_events_available() calls lockless and added single call under\na lock, finally commit e59d3c64cba6 (\"epoll: eliminate unnecessary lock\nfor zero timeout\") made the last ep_events_available() lockless.\n\nBUG: KCSAN: data-race in do_epoll_wait / do_epoll_wait\n\nwrite to 0xffff88810480c7d8 of 8 bytes by task 1802 on cpu 0:\n INIT_LIST_HEAD include/linux/list.h:38 [inline]\n list_splice_init include/linux/list.h:492 [inline]\n ep_start_scan fs/eventpoll.c:622 [inline]\n ep_send_events fs/eventpoll.c:1656 [inline]\n ep_poll fs/eventpoll.c:1806 [inline]\n do_epoll_wait+0x4eb/0xf40 fs/eventpoll.c:2234\n do_epoll_pwait fs/eventpoll.c:2268 [inline]\n __do_sys_epoll_pwait fs/eventpoll.c:2281 [inline]\n __se_sys_epoll_pwait+0x12b/0x240 fs/eventpoll.c:2275\n __x64_sys_epoll_pwait+0x74/0x80 fs/eventpoll.c:2275\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nread to 0xffff88810480c7d8 of 8 bytes by task 1799 on cpu 1:\n list_empty_careful include/linux/list.h:329 [inline]\n ep_events_available fs/eventpoll.c:381 [inline]\n ep_poll fs/eventpoll.c:1797 [inline]\n do_epoll_wait+0x279/0xf40 fs/eventpoll.c:2234\n do_epoll_pwait fs/eventpoll.c:2268 [inline]\n __do_sys_epoll_pwait fs/eventpoll.c:2281 [inline]\n __se_sys_epoll_pwait+0x12b/0x240 fs/eventpoll.c:2275\n __x64_sys_epoll_pwait+0x74/0x80 fs/eventpoll.c:2275\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nvalue changed: 0xffff88810480c7d0 -> 0xffff888103c15098\n\nReported by Kernel Concurrency Sanitizer on:\nCPU: 1 PID: 1799 Comm: syz-fuzzer Tainted: G        W         5.17.0-rc7-syzkaller-dirty #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011","publishedAt":"2025-02-26T02:12:55.959Z","updatedAt":"2026-05-11T18:59:55.294Z","severity":{"score":4.7,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"bf3b9f6372c45b0fbf24d86b8794910d20170017","status":"affected","lessThan":"5d5d993f16be15d124be7b8ec71b28ef7b7dc3af","versionType":"git"},{"version":"bf3b9f6372c45b0fbf24d86b8794910d20170017","status":"affected","lessThan":"cb3e48f7a35033deb9455abe3932e63cb500b9eb","versionType":"git"},{"version":"bf3b9f6372c45b0fbf24d86b8794910d20170017","status":"affected","lessThan":"e039c0b5985999b150594126225e1ee51df7b4c9","versionType":"git"},{"version":"bf3b9f6372c45b0fbf24d86b8794910d20170017","status":"affected","lessThan":"d679ae94fdd5d3ab00c35078f5af5f37e068b03d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/list.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.12","versionType":"semver"},{"version":"5.15.46","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.17.14","status":"unaffected","lessThanOrEqual":"5.17.*","versionType":"semver"},{"version":"5.18.3","status":"unaffected","lessThanOrEqual":"5.18.*","versionType":"semver"},{"version":"5.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/list.h"]}],"references":["https://git.kernel.org/stable/c/5d5d993f16be15d124be7b8ec71b28ef7b7dc3af","https://git.kernel.org/stable/c/cb3e48f7a35033deb9455abe3932e63cb500b9eb","https://git.kernel.org/stable/c/e039c0b5985999b150594126225e1ee51df7b4c9","https://git.kernel.org/stable/c/d679ae94fdd5d3ab00c35078f5af5f37e068b03d"],"weaknesses":["CWE-362"],"ingestedAt":"2026-10-29T20:05:26.763Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2022/49xxx/CVE-2022-49443.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-49443","state":"PUBLISHED","datePublished":"2025-02-26T02:12:55.959Z","dateUpdated":"2026-05-11T18:59:55.294Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-02-26T02:08:31.571Z"},"containers":{"cna":{"title":"list: fix a data-race around ep->rdllist","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nlist: fix a data-race around ep->rdllist\n\nep_poll() first calls ep_events_available() with no lock held and checks\nif ep->rdllist is empty by list_empty_careful(), which reads\nrdllist->prev.  Thus all accesses to it need some protection to avoid\nstore/load-tearing.\n\nNote INIT_LIST_HEAD_RCU() already has the annotation for both prev\nand next.\n\nCommit bf3b9f6372c4 (\"epoll: Add busy poll support to epoll with socket\nfds.\") added the first lockless ep_events_available(), and commit\nc5a282e9635e (\"fs/epoll: reduce the scope of wq lock in epoll_wait()\")\nmade some ep_events_available() calls lockless and added single call under\na lock, finally commit e59d3c64cba6 (\"epoll: eliminate unnecessary lock\nfor zero timeout\") made the last ep_events_available() lockless.\n\nBUG: KCSAN: data-race in do_epoll_wait / do_epoll_wait\n\nwrite to 0xffff88810480c7d8 of 8 bytes by task 1802 on cpu 0:\n INIT_LIST_HEAD include/linux/list.h:38 [inline]\n list_splice_init include/linux/list.h:492 [inline]\n ep_start_scan fs/eventpoll.c:622 [inline]\n ep_send_events fs/eventpoll.c:1656 [inline]\n ep_poll fs/eventpoll.c:1806 [inline]\n do_epoll_wait+0x4eb/0xf40 fs/eventpoll.c:2234\n do_epoll_pwait fs/eventpoll.c:2268 [inline]\n __do_sys_epoll_pwait fs/eventpoll.c:2281 [inline]\n __se_sys_epoll_pwait+0x12b/0x240 fs/eventpoll.c:2275\n __x64_sys_epoll_pwait+0x74/0x80 fs/eventpoll.c:2275\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nread to 0xffff88810480c7d8 of 8 bytes by task 1799 on cpu 1:\n list_empty_careful include/linux/list.h:329 [inline]\n ep_events_available fs/eventpoll.c:381 [inline]\n ep_poll fs/eventpoll.c:1797 [inline]\n do_epoll_wait+0x279/0xf40 fs/eventpoll.c:2234\n do_epoll_pwait fs/eventpoll.c:2268 [inline]\n __do_sys_epoll_pwait fs/eventpoll.c:2281 [inline]\n __se_sys_epoll_pwait+0x12b/0x240 fs/eventpoll.c:2275\n __x64_sys_epoll_pwait+0x74/0x80 fs/eventpoll.c:2275\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nvalue changed: 0xffff88810480c7d0 -> 0xffff888103c15098\n\nReported by Kernel Concurrency Sanitizer on:\nCPU: 1 PID: 1799 Comm: syz-fuzzer Tainted: G        W         5.17.0-rc7-syzkaller-dirty #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"bf3b9f6372c45b0fbf24d86b8794910d20170017","status":"affected","lessThan":"5d5d993f16be15d124be7b8ec71b28ef7b7dc3af","versionType":"git"},{"version":"bf3b9f6372c45b0fbf24d86b8794910d20170017","status":"affected","lessThan":"cb3e48f7a35033deb9455abe3932e63cb500b9eb","versionType":"git"},{"version":"bf3b9f6372c45b0fbf24d86b8794910d20170017","status":"affected","lessThan":"e039c0b5985999b150594126225e1ee51df7b4c9","versionType":"git"},{"version":"bf3b9f6372c45b0fbf24d86b8794910d20170017","status":"affected","lessThan":"d679ae94fdd5d3ab00c35078f5af5f37e068b03d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/list.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.12","versionType":"semver"},{"version":"5.15.46","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.17.14","status":"unaffected","lessThanOrEqual":"5.17.*","versionType":"semver"},{"version":"5.18.3","status":"unaffected","lessThanOrEqual":"5.18.*","versionType":"semver"},{"version":"5.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/list.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/5d5d993f16be15d124be7b8ec71b28ef7b7dc3af"},{"url":"https://git.kernel.org/stable/c/cb3e48f7a35033deb9455abe3932e63cb500b9eb"},{"url":"https://git.kernel.org/stable/c/e039c0b5985999b150594126225e1ee51df7b4c9"},{"url":"https://git.kernel.org/stable/c/d679ae94fdd5d3ab00c35078f5af5f37e068b03d"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T18:59:55.294Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.15.46"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.17.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.18.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.19"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":4.7,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"HIGH","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2022-49443","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T19:40:52.947192Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-362","lang":"en","type":"CWE","description":"CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T19:46:49.208Z"}}]}}}