{"cve":"CVE-2026-53331","nvd":{"published":"2026-07-01T14:16:40.997","modified":"2026-07-23T21:33:58.167","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nslimbus: qcom-ngd-ctrl: Avoid ABBA on tx_lock/ctrl->lock\n\nDuring the SSR/PDR down notification the tx_lock is taken with the\nintent to provide synchronization with active DMA transfers.\n\nBut during this period qcom_slim_ngd_down() is invoked, which ends up in\nslim_report_absent(), which takes the slim_controller lock. In multiple\nother codepaths these two locks are taken in the opposite order (i.e.\nslim_controller then tx_lock).\n\nThe result is a lockdep splat, and a possible deadlock:\n\n  rprocctl/449 is trying to acquire lock:\n  ffff00009793e620 (&ctrl->lock){+.+.}-{4:4}, at: slim_report_absent (drivers/slimbus/core.c:322) slimbus\n\n  but task is already holding lock:\n  ffff00009793fb50 (&ctrl->tx_lock){+.+.}-{4:4}, at: qcom_slim_ngd_ssr_pdr_notify (drivers/slimbus/qcom-ngd-ctrl.c:1475) slim_qcom_ngd_ctrl\n\n  which lock already depends on the new lock.\n\n  Possible unsafe locking scenario:\n\n        CPU0                    CPU1\n        ----                    ----\n   lock(&ctrl->tx_lock);\n                                lock(&ctrl->lock);\n                                lock(&ctrl->tx_lock);\n   lock(&ctrl->lock);\n\nThe assumption is that the comment refers to the desire to not call\nqcom_slim_ngd_exit_dma() while we have an ongoing DMA TX transaction.\nBut any such transaction is initiated and completed within a single\nqcom_slim_ngd_xfer_msg().\n\nPrior to calling qcom_slim_ngd_exit_dma() the slim_controller is torn\ndown, all child devices are notified that the slimbus is gone and the\nchild devices are removed.\n\nStop taking the tx_lock in qcom_slim_ngd_ssr_pdr_notify() to avoid the\ndeadlock.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/3d1561537237c6cc1db76155183d8bbdac2339f0","https://git.kernel.org/stable/c/55f2ea9ff83cc27a85526b14bc9b32f96a08d6ec","https://git.kernel.org/stable/c/9708eb50fd7343145b422be852f890212155d845","https://git.kernel.org/stable/c/9f0d45d509b434c54da10e01f4ef8086e4583401","https://git.kernel.org/stable/c/aad4337a21b9ad3ae8d668fa8678d05e26ecbaa8"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:42:16.820116992+00:00"},"epss":{"cve":"CVE-2026-53331","score":0.00129,"percentile":0.02563,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}