{"id":"CVE-2026-53331","summary":"slimbus: qcom-ngd-ctrl: Avoid ABBA on tx_lock/ctrl-\u003elock","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nslimbus: qcom-ngd-ctrl: Avoid ABBA on tx_lock/ctrl-\u003elock\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-\u003elock){+.+.}-{4:4}, at: slim_report_absent (drivers/slimbus/core.c:322) slimbus\n\n  but task is already holding lock:\n  ffff00009793fb50 (&ctrl-\u003etx_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-\u003etx_lock);\n                                lock(&ctrl-\u003elock);\n                                lock(&ctrl-\u003etx_lock);\n   lock(&ctrl-\u003elock);\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.","modified":"2026-07-08T08:07:25.177897944Z","published":"2026-07-01T13:32:15.733Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53331.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/3d1561537237c6cc1db76155183d8bbdac2339f0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/55f2ea9ff83cc27a85526b14bc9b32f96a08d6ec"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9708eb50fd7343145b422be852f890212155d845"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9f0d45d509b434c54da10e01f4ef8086e4583401"},{"type":"WEB","url":"https://git.kernel.org/stable/c/aad4337a21b9ad3ae8d668fa8678d05e26ecbaa8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d54a221b0f3cd9e1f03f18104be34e02a8258fae"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dc4d5c57e012c2c669793deb1515a57bbc6bf5dd"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53331.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53331"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"a899d324863a3d15ce0eea513884e1b73a758c58"},{"fixed":"3d1561537237c6cc1db76155183d8bbdac2339f0"},{"fixed":"dc4d5c57e012c2c669793deb1515a57bbc6bf5dd"},{"fixed":"d54a221b0f3cd9e1f03f18104be34e02a8258fae"},{"fixed":"aad4337a21b9ad3ae8d668fa8678d05e26ecbaa8"},{"fixed":"9f0d45d509b434c54da10e01f4ef8086e4583401"},{"fixed":"9708eb50fd7343145b422be852f890212155d845"},{"fixed":"55f2ea9ff83cc27a85526b14bc9b32f96a08d6ec"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53331.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.210"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.176"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.143"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.94"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.36"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.13"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53331.json"}}],"schema_version":"1.7.5"}