CVE-2026-46025

{"id": "CVE-2026-46025", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"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"}, "impactScore": 3.6, "exploitabilityScore": 1.0}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "42b7491af14cbba2393329ce43d508a957bd94fa", "lessThan": "2691332ad88b57179c38653e2cd613d5820a52cf", "versionType": "git"}, {"status": "affected", "version": "42b7491af14cbba2393329ce43d508a957bd94fa", "lessThan": "e6a053a6f4b5048746c49432a5cc5b79fe4695fe", "versionType": "git"}, {"status": "affected", "version": "42b7491af14cbba2393329ce43d508a957bd94fa", "lessThan": "55da81663b9642dd046b26dd6f1baddbcf337c1e", "versionType": "git"}], "programFiles": ["include/linux/damon.h", "mm/damon/core.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.14"}, {"status": "unaffected", "version": "0", "lessThan": "6.14", "versionType": "semver"}, {"status": "unaffected", "version": "6.18.27", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.4", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["include/linux/damon.h", "mm/damon/core.c"], "defaultStatus": "affected"}]}], "published": "2026-05-27T14:17:21.013", "references": [{"url": "https://git.kernel.org/stable/c/2691332ad88b57179c38653e2cd613d5820a52cf", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/55da81663b9642dd046b26dd6f1baddbcf337c1e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e6a053a6f4b5048746c49432a5cc5b79fe4695fe", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-362"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/core: fix damon_call() vs kdamond_fn() exit race\n\nPatch series \"mm/damon/core: fix damon_call()/damos_walk() vs kdmond exit\nrace\".\n\ndamon_call() and damos_walk() can leak memory and/or deadlock when they\nrace with kdamond terminations. Fix those.\n\n\nThis patch (of 2);\n\nWhen kdamond_fn() main loop is finished, the function cancels all\nremaining damon_call() requests and unset the damon_ctx->kdamond so that\nAPI callers and API functions themselves can know the context is\nterminated. damon_call() adds the caller's request to the queue first. \nAfter that, it shows if the kdamond of the damon_ctx is still running\n(damon_ctx->kdamond is set). Only if the kdamond is running, damon_call()\nstarts waiting for the kdamond's handling of the newly added request.\n\nThe damon_call() requests registration and damon_ctx->kdamond unset are\nprotected by different mutexes, though. Hence, damon_call() could race\nwith damon_ctx->kdamond unset, and result in deadlocks.\n\nFor example, let's suppose kdamond successfully finished the damon_call()\nrequests cancelling. Right after that, damon_call() is called for the\ncontext. It registers the new request, and shows the context is still\nrunning, because damon_ctx->kdamond unset is not yet done. Hence the\ndamon_call() caller starts waiting for the handling of the request. \nHowever, the kdamond is already on the termination steps, so it never\nhandles the new request. As a result, the damon_call() caller threads\ninfinitely waits.\n\nFix this by introducing another damon_ctx field, namely\ncall_controls_obsolete. It is protected by the\ndamon_ctx->call_controls_lock, which protects damon_call() requests\nregistration. Initialize (unset) it in kdamond_fn() before letting\ndamon_start() returns and set it just before the cancelling of remaining\ndamon_call() requests is executed. damon_call() reads the obsolete field\nunder the lock and avoids adding a new request.\n\nAfter this change, only requests that are guaranteed to be handled or\ncancelled are registered. Hence the after-registration DAMON context\ntermination check is no longer needed. Remove it together.\n\nNote that the deadlock will not happen when damon_call() is called for\nrepeat mode request. In tis case, damon_call() returns instead of waiting\nfor the handling when the request registration succeeds and it shows the\nkdamond is running. However, if the request also has dealloc_on_cancel,\nthe request memory would be leaked.\n\nThe issue is found by sashiko [1]."}], "lastModified": "2026-06-17T10:52:55.270", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "09521A36-58DA-4204-AE3E-627063BA9807", "versionEndExcluding": "6.18.27", "versionStartIncluding": "6.14"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CDB78D6D-22C3-4154-B0D0-94AF1CE5C2E3", "versionEndExcluding": "7.0.4", "versionStartIncluding": "6.19"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}