{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-90309", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.800Z", "datePublished": "2026-09-17T16:08:30.346Z", "dateUpdated": "2026-10-19T09:01:26.909Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:01:26.909Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/erdma: Hold CQ references when processing EQ events\n\nEQ handlers look up CQs from dev->cq_xa and invoke CQ completion or\nerror callbacks outside the xarray lock. erdma_destroy_cq() can erase the\nCQ from the xarray and free its queue buffer and doorbell record while a\npreviously scheduled EQ handler is still using the CQ.\n\nAdd a CQ refcount and take a reference under the xarray lock with\nrefcount_inc_not_zero(). Remove the CQ from the xarray before dropping\nthe destroy-path reference, then wait for in-flight EQ users before\nreleasing CQ resources." } ], "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 UAF is reached by IB_USER_VERBS_CMD_DESTROY_CQ/UVERBS_METHOD_CQ_DESTROY on /dev/infiniband/uverbsN racing erdma_ceq_completion_handler and erdma_aeq_event_handler; CEQE/AEQE CQNs are written by the ERDMA NIC for locally created CQs, not parsed from a remote RoCE/iWARP message.\nAC:L - The attacker drives both sides: userspace SQ/RQ doorbells via erdma_mmap (or ib_uverbs_post_send) make the NIC post CEQEs and schedule the CEQ tasklet, while another thread runs ib_uverbs_destroy_cq; pre-fix erdma_destroy_cq xa_erase'd the CQ with no ref wait, so the race is attacker-controlled.\nPR:L - ib_uverbs_open allows CQ create/destroy with no capability check; uverbs_devnode sets /dev/infiniband/uverbsN to mode 0666, and erdma_alloc_ucontext/erdma_create_cq/erdma_destroy_cq do not require CAP_NET_ADMIN or init-namespace root.\nUI:N - The attacker creates the CQ via ib_uverbs_create_cq, generates EQ events from their own QPs, and tears it down via ib_uverbs_destroy_cq/uverbs_free_cq on that uverbs fd; no other user must mount, open a file, or otherwise act.\nS:U - The dangling erdma_cq is used inside the same host kernel that issued the uverbs destroy (comp_handler/event_handler on ibcq); this is in-kernel privilege escalation, not a KVM/Xen guest-to-host or IOMMU/DMA boundary bypass.\nC:H - After ib_destroy_cq_user kfree(cq), erdma_ceq_completion_handler still reads cq->ibcq.comp_handler and cq->ibcq.cq_context from the freed object, and ib_uverbs_comp_handler then follows cq->uobject, giving a UAF read of kernel heap.\nI:H - The same dangling pointer is used to invoke cq->ibcq.comp_handler (and on AEQ CQ_ERR, cq->ibcq.event_handler); kernel CQs also do cq->kern_cq.cmdsn++. Calling a function pointer from a freed erdma_cq is an arbitrary-write/control-flow hijack primitive.\nA:H - erdma_ceq_completion_handler or erdma_aeq_event_handler dereferencing the kfree'd erdma_cq (junk comp_handler/uobject) oopses the kernel, and repeating create_cq/destroy_cq while CEQ/AEQ events are in flight panics the host." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/infiniband/hw/erdma/erdma_eq.c", "drivers/infiniband/hw/erdma/erdma_verbs.c", "drivers/infiniband/hw/erdma/erdma_verbs.h" ], "versions": [ { "version": "155055771704f8cbb5c176a4309b7dc30a50450c", "lessThan": "610ef81797bb4f709e8675c1d8d093bb9ccdcbd8", "status": "affected", "versionType": "git" }, { "version": "155055771704f8cbb5c176a4309b7dc30a50450c", "lessThan": "c0a83f29a24c7e7f8516630848ef6db4c174deed", "status": "affected", "versionType": "git" }, { "version": "155055771704f8cbb5c176a4309b7dc30a50450c", "lessThan": "05b8ca493dd02319bca93c640b259c2ba51ef321", "status": "affected", "versionType": "git" }, { "version": "155055771704f8cbb5c176a4309b7dc30a50450c", "lessThan": "1fc9c1933959d2776a1ce7bf424251b8b5b586cd", "status": "affected", "versionType": "git" }, { "version": "155055771704f8cbb5c176a4309b7dc30a50450c", "lessThan": "4545f355654d044d35a31cd01cc46f491a8a7c36", "status": "affected", "versionType": "git" }, { "version": "155055771704f8cbb5c176a4309b7dc30a50450c", "lessThan": "98df2aee1459ee1c62c70cbe9b370d2a532aea36", "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/infiniband/hw/erdma/erdma_eq.c", "drivers/infiniband/hw/erdma/erdma_verbs.c", "drivers/infiniband/hw/erdma/erdma_verbs.h" ], "versions": [ { "version": "6.0", "status": "affected" }, { "version": "0", "lessThan": "6.0", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.6", "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": "6.0", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.12.110" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.18.52" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "7.2.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/610ef81797bb4f709e8675c1d8d093bb9ccdcbd8" }, { "url": "https://git.kernel.org/stable/c/c0a83f29a24c7e7f8516630848ef6db4c174deed" }, { "url": "https://git.kernel.org/stable/c/05b8ca493dd02319bca93c640b259c2ba51ef321" }, { "url": "https://git.kernel.org/stable/c/1fc9c1933959d2776a1ce7bf424251b8b5b586cd" }, { "url": "https://git.kernel.org/stable/c/4545f355654d044d35a31cd01cc46f491a8a7c36" }, { "url": "https://git.kernel.org/stable/c/98df2aee1459ee1c62c70cbe9b370d2a532aea36" } ], "title": "RDMA/erdma: Hold CQ references when processing EQ events", "x_generator": { "engine": "bippy-1.2.0" } } } }