{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89994", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.780Z", "datePublished": "2026-09-16T10:33:07.292Z", "dateUpdated": "2026-10-19T08:56:08.384Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:56:08.384Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndmaengine: fsl-edma: tracing: no ptr dereference during log output\n\nThe fsl edma events store a pointer to a struct fsl_edma_engine in the\nringbuffer and dereference it when a log entry is printed. At this time,\nthe pointer may no longer be valid.\n\nEvent injection can be used to trigger a crash:\n\n$ cd /sys/kernel/tracing\n$ echo 'value = 0' > events/fsl_edma/edma_writeb/inject\n$ cat trace\n\nThe log output needs only edma->membase. Add a membase field at the end\nof the event and use the new field for log output. Keep the existing\nfields for backward compatibility." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The stale dereference runs only when a local actor reads formatted fsl_edma events from tracefs (/sys/kernel/tracing/trace or trace_pipe). DMA MMIO tracing and event injection only enqueue ring-buffer records; there is no network, adjacent-radio, or physical-device path into TP_printk().\nAC:L - An attacker with tracefs access controls the full sequence: enable edma_log_io events, either inject a record via events/fsl_edma/*/inject or generate eDMA I/O then unbind/remove fsl-edma so the stored engine pointer is freed, then read trace. No race or uninfluenced victim state is required.\nPR:L - tracing_check_open_get_tr() enforces only LOCKDOWN_TRACEFS and DAC, with no capable() check. Event enable and trace files are mode 0640 and are routinely delegated via tracefs gid= to tracing-group members on Android Automotive/NXP i.MX, ChromeOS, and developer kernels, matching prior TP_printk UAF CVEs.\nUI:N - No victim interaction is required. The attacker enables fsl_edma events, injects or records a stale edma pointer, and reads the formatted trace themselves to invoke the vulnerable TP_printk() path.\nS:U - Impact stays inside the host kernel's trace formatting path (stale fsl_edma_engine dereference). This is standard local kernel memory-safety impact with no VM escape, IOMMU/DMA boundary bypass, or other cross-authority effect; membase is used only for log offset arithmetic.\nC:H - TP_printk() dereferences __entry->edma->membase when formatting output. That is a use-after-free read of a freed fsl_edma_engine, and with event injection the edma field is attacker-chosen, yielding an arbitrary kernel pointer read whose result is printed as the register offset.\nI:H - The bug is a use-after-free of the kernel heap object fsl_edma_engine, which embeds dma_device function pointers. Freed memory can be reclaimed before the trace read, enabling heap grooming and write/control-flow primitives; kernel CNA guidance rates UAF integrity impact as High.\nA:H - Dereferencing a NULL (inject with a zeroed edma pointer) or freed fsl_edma_engine pointer during trace formatting causes a kernel oops or panic. The fix commit demonstrates a deterministic crash via inject followed by cat trace." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/dma/fsl-edma-trace.h" ], "versions": [ { "version": "11102d0c343ba06ddd303f2503c0ce46d70052f2", "lessThan": "ef02cd3807f39ae1dbc924788d8fa6a85334c435", "status": "affected", "versionType": "git" }, { "version": "11102d0c343ba06ddd303f2503c0ce46d70052f2", "lessThan": "d382aaf5fed38c6dd2e0cc710d97cb81d660ffa7", "status": "affected", "versionType": "git" }, { "version": "11102d0c343ba06ddd303f2503c0ce46d70052f2", "lessThan": "2a3801ae5c344473e648006c5b03a9216ac54a6a", "status": "affected", "versionType": "git" }, { "version": "11102d0c343ba06ddd303f2503c0ce46d70052f2", "lessThan": "2ea04dca8e627f722caa7a2037cfbae0257f3501", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/dma/fsl-edma-trace.h" ], "versions": [ { "version": "6.10", "status": "affected" }, { "version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.51", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.5", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "6.10", "versionEndExcluding": "6.12.110" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.18.51" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.2.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ef02cd3807f39ae1dbc924788d8fa6a85334c435" }, { "url": "https://git.kernel.org/stable/c/d382aaf5fed38c6dd2e0cc710d97cb81d660ffa7" }, { "url": "https://git.kernel.org/stable/c/2a3801ae5c344473e648006c5b03a9216ac54a6a" }, { "url": "https://git.kernel.org/stable/c/2ea04dca8e627f722caa7a2037cfbae0257f3501" } ], "title": "dmaengine: fsl-edma: tracing: no ptr dereference during log output", "x_generator": { "engine": "bippy-1.2.0" } } } }