{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2022-49768", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:17:33.804Z", "datePublished": "2025-05-01T14:09:06.864Z", "dateUpdated": "2026-08-05T08:56:16.608Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:56:16.608Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\n9p: trans_fd/p9_conn_cancel: drop client lock earlier\n\nsyzbot reported a double-lock here and we no longer need this\nlock after requests have been moved off to local list:\njust drop the lock earlier." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The recursive deadlock is reached from p9_read_work()/p9_poll_mux() on the TCP (and unix) fd transport when processing peer-driven I/O errors or malformed replies; a remote malicious 9p server can close the connection or send bad headers/tags over the established TCP session to enter p9_conn_cancel().\nAC:L - After a request is fully written the writer has already put its ref, leaving the waiting client with refcount 1; the remote peer can then deterministically force cancel (ECONNRESET, bad header, unexpected tag), so p9_client_cb()'s final p9_req_put() re-takes client->lock with no race outside attacker control.\nPR:N - The attacker is the remote 9p server and needs no credentials or capabilities on the client; reply/error handling on the transport runs without authentication or privilege checks, matching other trans_fd peer-driven 9p client bugs.\nUI:N - Exploitation rides an already-configured or automounted 9p TCP session and server-driven errors/replies; the mount is a deployment precondition, not a required victim action beyond ordinary use of that mount.\nS:U - Impact is a host-kernel deadlock inside the 9p client on the same OS security authority; there is no VM escape, IOMMU bypass, or other cross-boundary effect.\nC:N - This is a pure recursive spinlock deadlock (p9_conn_cancel → p9_client_cb → p9_req_put → p9_tag_remove on the same client->lock); it does not free early, leak, or otherwise disclose kernel memory.\nI:N - There is no memory corruption, UAF, or write primitive—only nested acquisition of the same non-recursive spinlock—so control-flow hijack or arbitrary modification is not available.\nA:H - Re-taking client->lock while already holding it deadlocks the p9_read_work kworker with preemption disabled, hangs all further 9p operations on that client, and can soft-lockup the CPU; syzbot reported the recursive lock in p9_req_put from this path." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/9p/trans_fd.c" ], "versions": [ { "version": "eb1ca07f4343b4e58b97e792a85d5ba1ba103f5d", "lessThan": "82825dbf393f7c7979d462f9609a15bde8092b3f", "status": "affected", "versionType": "git" }, { "version": "4cd195263e420311d31451cc053fde8037f326f1", "lessThan": "e3031280fe4eaf61a09e60823331f81f321be8e1", "status": "affected", "versionType": "git" }, { "version": "9f476d7c540cb57556d3cc7e78704e6cd5100f5f", "lessThan": "fec1406f5e7ab20b71f6d231792b0040e3300aaf", "status": "affected", "versionType": "git" }, { "version": "9f476d7c540cb57556d3cc7e78704e6cd5100f5f", "lessThan": "96760723aae1b45f733f702abb4333137143909f", "status": "affected", "versionType": "git" }, { "version": "9f476d7c540cb57556d3cc7e78704e6cd5100f5f", "lessThan": "f14858bc77c567e089965962877ee726ffad0556", "status": "affected", "versionType": "git" }, { "version": "9f476d7c540cb57556d3cc7e78704e6cd5100f5f", "lessThan": "a4f1a01b2e81378fce9ca528d4d8a049e4b58fcd", "status": "affected", "versionType": "git" }, { "version": "9f476d7c540cb57556d3cc7e78704e6cd5100f5f", "lessThan": "612c977f5d481f551d03d83d0aef588845c1300c", "status": "affected", "versionType": "git" }, { "version": "9f476d7c540cb57556d3cc7e78704e6cd5100f5f", "lessThan": "52f1c45dde9136f964d63a77d19826c8a74e2c7f", "status": "affected", "versionType": "git" }, { "version": "91ca7c5644c370dc5132b1db1aea81416a4b2181", "status": "affected", "versionType": "git" }, { "version": "4.9.127", "lessThan": "4.9.334", "status": "affected", "versionType": "semver" }, { "version": "4.14.70", "lessThan": "4.14.300", "status": "affected", "versionType": "semver" }, { "version": "4.18.8", "lessThan": "4.19", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/9p/trans_fd.c" ], "versions": [ { "version": "4.19", "status": "affected" }, { "version": "0", "lessThan": "4.19", "status": "unaffected", "versionType": "semver" }, { "version": "4.9.334", "lessThanOrEqual": "4.9.*", "status": "unaffected", "versionType": "semver" }, { "version": "4.14.300", "lessThanOrEqual": "4.14.*", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.267", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.225", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.156", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.80", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.0.10", "lessThanOrEqual": "6.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.9.127", "versionEndExcluding": "4.9.334" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14.70", "versionEndExcluding": "4.14.300" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "4.19.267" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "5.4.225" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "5.10.156" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "5.15.80" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "6.0.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "6.1" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18.8" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/82825dbf393f7c7979d462f9609a15bde8092b3f" }, { "url": "https://git.kernel.org/stable/c/e3031280fe4eaf61a09e60823331f81f321be8e1" }, { "url": "https://git.kernel.org/stable/c/fec1406f5e7ab20b71f6d231792b0040e3300aaf" }, { "url": "https://git.kernel.org/stable/c/96760723aae1b45f733f702abb4333137143909f" }, { "url": "https://git.kernel.org/stable/c/f14858bc77c567e089965962877ee726ffad0556" }, { "url": "https://git.kernel.org/stable/c/a4f1a01b2e81378fce9ca528d4d8a049e4b58fcd" }, { "url": "https://git.kernel.org/stable/c/612c977f5d481f551d03d83d0aef588845c1300c" }, { "url": "https://git.kernel.org/stable/c/52f1c45dde9136f964d63a77d19826c8a74e2c7f" } ], "title": "9p: trans_fd/p9_conn_cancel: drop client lock earlier", "x_generator": { "engine": "bippy-1.2.0" } } } }