{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-72473", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.934Z", "datePublished": "2026-08-15T05:57:14.412Z", "dateUpdated": "2026-08-15T05:57:14.412Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-15T05:57:14.412Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxprtrdma: Decouple req recycling from RPC completion\n\nrl_kref formerly served two distinct lifetimes through a single\nrefcount: it gated when a Reply could wake its RPC task, and it\ngated when an rpcrdma_req could return to its free pool. The\nmarshal path took the Send-side reference only when SGEs needed\nDMA-unmap (sc_unmap_count > 0), which made a Send carrying only\npre-registered buffers an exception: the Reply handler dropped\nrl_kref from 1 to 0 and freed the req while the HCA might still\nbe DMA-reading from its send buffer.\n\nGive rl_kref a narrower job. The RPC layer takes one reference\nwhen slot allocation hands a req out. rpcrdma_prepare_send_sges()\ntakes a Send-side reference unconditionally after WR preparation\nsucceeds. xprt_rdma_free_slot() and xprt_rdma_bc_free_rqst() drop\nthe RPC-layer reference; rpcrdma_sendctx_unmap() drops the\nSend-side reference. The req returns to its free pool only after\nboth owners have signed off.\n\nThe existing kref_init(&req->rl_kref) call in\nrpcrdma_prepare_send_sges() is removed. Initialization moves to\nthe slot-allocation paths (xprt_rdma_alloc_slot and\nrpcrdma_bc_rqst_get), and the release callback re-arms rl_kref\nbefore the req returns to a free pool. A re-init in the marshal\npath would discard the RPC-layer reference that already exists\non entry.\n\nThree invariants follow:\n\n - Any rpcrdma_req held by an rpc_rqst has rl_kref >= 1.\n xprt_rdma_alloc_slot(), rpcrdma_bc_rqst_get(), and the\n backlog-wake branch in xprt_rdma_alloc_slot() each kref_init\n rl_kref before publishing the req. Without this invariant,\n an RPC task that aborts between slot allocation and marshal\n (gss_refresh failure or signal during call_connect, for\n example) would drive xprt_release() ->\n xprt_rdma_free_slot() -> kref_put against a refcount of\n zero, saturating refcount_t and stranding the slot.\n\n - The Send-side reference is taken only after WR prep\n succeeds. A mapping failure in rpcrdma_prepare_send_sges()\n runs rpcrdma_sendctx_cancel(), which DMA-unmaps the sendctx\n and clears sc_req without touching rl_kref. The sendctx\n ring walks in rpcrdma_sendctx_put_locked() and\n rpcrdma_sendctxs_destroy() skip entries with sc_req == NULL,\n so a burst of -EIO marshal failures cannot hold reqs off\n rb_send_bufs.\n\n - The release callback re-arms rl_kref so the next consumer\n enters with the invariant satisfied.\n\nReplies now complete the RPC directly. rpcrdma_reply_handler()\ncalls rpcrdma_complete_rqst() in place of kref_put on the\nnon-LocalInv branch. The LocalInv branch already completes the\nRPC from frwr_unmap_async() and is unaffected.\n\nBecause Send-side references can now outlive RPC completion,\nconnection teardown drains sendctx entries whose unsignaled\nSends never had a later signaled completion to walk the ring.\nrpcrdma_sendctxs_destroy() walks the active range and runs\nrpcrdma_sendctx_unmap() on each entry with a non-NULL sc_req\nbefore the request buffers are reset, and is moved ahead of\nrpcrdma_reqs_reset() in rpcrdma_xprt_disconnect() so the reqs\nare still in their pre-reset state when the Send-side refs are\nreleased.\n\nThe drain creates a teardown-ordering hazard on the backchannel\npath. With the new lifetime, releasing a bc_prealloc req from\nrpcrdma_req_release() re-adds it to bc_pa_list. The disconnect\nin xprt_rdma_destroy() runs after xprt_destroy_backchannel() has\nalready emptied bc_pa_list, so the drained reqs would otherwise\nleak. xprt_rdma_destroy() now runs xprt_rdma_bc_destroy(xprt, 0)\na second time after the disconnect to reclaim them."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/sunrpc/xprtrdma/backchannel.c", "net/sunrpc/xprtrdma/rpc_rdma.c", "net/sunrpc/xprtrdma/transport.c", "net/sunrpc/xprtrdma/verbs.c", "net/sunrpc/xprtrdma/xprt_rdma.h"], "versions": [{"version": "0ab115237025f5e379620bbcd56a02697d07b002", "lessThan": "740975054a1970c0cf15f70ac39724a064f45847", "status": "affected", "versionType": "git"}, {"version": "0ab115237025f5e379620bbcd56a02697d07b002", "lessThan": "9f3d9b68c1c6c51746e5ecdb52b2e6a2901de37e", "status": "affected", "versionType": "git"}, {"version": "0ab115237025f5e379620bbcd56a02697d07b002", "lessThan": "e7632089523acddcdd8f090ad19e96fb3107b04d", "status": "affected", "versionType": "git"}, {"version": "0ab115237025f5e379620bbcd56a02697d07b002", "lessThan": "53442c7d0c888e51b8bc3da196970a669cc6b294", "status": "affected", "versionType": "git"}, {"version": "0ab115237025f5e379620bbcd56a02697d07b002", "lessThan": "8203f760a72bd39a3b66bc4eff0aa272a99fe22b", "status": "affected", "versionType": "git"}, {"version": "0ab115237025f5e379620bbcd56a02697d07b002", "lessThan": "e786233d2e0bbff9a82e43f02ae3a46ab4b08ec3", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/sunrpc/xprtrdma/backchannel.c", "net/sunrpc/xprtrdma/rpc_rdma.c", "net/sunrpc/xprtrdma/transport.c", "net/sunrpc/xprtrdma/verbs.c", "net/sunrpc/xprtrdma/xprt_rdma.h"], "versions": [{"version": "5.3", "status": "affected"}, {"version": "0", "lessThan": "5.3", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2-rc1", "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": "5.3", "versionEndExcluding": "6.1.178"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.6.145"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.12.97"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.18.40"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "7.1.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "7.2-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/740975054a1970c0cf15f70ac39724a064f45847"}, {"url": "https://git.kernel.org/stable/c/9f3d9b68c1c6c51746e5ecdb52b2e6a2901de37e"}, {"url": "https://git.kernel.org/stable/c/e7632089523acddcdd8f090ad19e96fb3107b04d"}, {"url": "https://git.kernel.org/stable/c/53442c7d0c888e51b8bc3da196970a669cc6b294"}, {"url": "https://git.kernel.org/stable/c/8203f760a72bd39a3b66bc4eff0aa272a99fe22b"}, {"url": "https://git.kernel.org/stable/c/e786233d2e0bbff9a82e43f02ae3a46ab4b08ec3"}], "title": "xprtrdma: Decouple req recycling from RPC completion", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/sunrpc/xprtrdma/backchannel.c", "net/sunrpc/xprtrdma/rpc_rdma.c", "net/sunrpc/xprtrdma/transport.c", "net/sunrpc/xprtrdma/verbs.c", "net/sunrpc/xprtrdma/xprt_rdma.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "740975054a1970c0cf15f70ac39724a064f45847", "status": "affected", "version": "0ab115237025f5e379620bbcd56a02697d07b002", "versionType": "git"}, {"lessThan": "9f3d9b68c1c6c51746e5ecdb52b2e6a2901de37e", "status": "affected", "version": "0ab115237025f5e379620bbcd56a02697d07b002", "versionType": "git"}, {"lessThan": "e7632089523acddcdd8f090ad19e96fb3107b04d", "status": "affected", "version": "0ab115237025f5e379620bbcd56a02697d07b002", "versionType": "git"}, {"lessThan": "53442c7d0c888e51b8bc3da196970a669cc6b294", "status": "affected", "version": "0ab115237025f5e379620bbcd56a02697d07b002", "versionType": "git"}, {"lessThan": "8203f760a72bd39a3b66bc4eff0aa272a99fe22b", "status": "affected", "version": "0ab115237025f5e379620bbcd56a02697d07b002", "versionType": "git"}, {"lessThan": "e786233d2e0bbff9a82e43f02ae3a46ab4b08ec3", "status": "affected", "version": "0ab115237025f5e379620bbcd56a02697d07b002", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/sunrpc/xprtrdma/backchannel.c", "net/sunrpc/xprtrdma/rpc_rdma.c", "net/sunrpc/xprtrdma/transport.c", "net/sunrpc/xprtrdma/verbs.c", "net/sunrpc/xprtrdma/xprt_rdma.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.3"}, {"lessThan": "5.3", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.178", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.145", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.97", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.40", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.5", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2-rc1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxprtrdma: Decouple req recycling from RPC completion\n\nrl_kref formerly served two distinct lifetimes through a single\nrefcount: it gated when a Reply could wake its RPC task, and it\ngated when an rpcrdma_req could return to its free pool. The\nmarshal path took the Send-side reference only when SGEs needed\nDMA-unmap (sc_unmap_count > 0), which made a Send carrying only\npre-registered buffers an exception: the Reply handler dropped\nrl_kref from 1 to 0 and freed the req while the HCA might still\nbe DMA-reading from its send buffer.\n\nGive rl_kref a narrower job. The RPC layer takes one reference\nwhen slot allocation hands a req out. rpcrdma_prepare_send_sges()\ntakes a Send-side reference unconditionally after WR preparation\nsucceeds. xprt_rdma_free_slot() and xprt_rdma_bc_free_rqst() drop\nthe RPC-layer reference; rpcrdma_sendctx_unmap() drops the\nSend-side reference. The req returns to its free pool only after\nboth owners have signed off.\n\nThe existing kref_init(&req->rl_kref) call in\nrpcrdma_prepare_send_sges() is removed. Initialization moves to\nthe slot-allocation paths (xprt_rdma_alloc_slot and\nrpcrdma_bc_rqst_get), and the release callback re-arms rl_kref\nbefore the req returns to a free pool. A re-init in the marshal\npath would discard the RPC-layer reference that already exists\non entry.\n\nThree invariants follow:\n\n - Any rpcrdma_req held by an rpc_rqst has rl_kref >= 1.\n xprt_rdma_alloc_slot(), rpcrdma_bc_rqst_get(), and the\n backlog-wake branch in xprt_rdma_alloc_slot() each kref_init\n rl_kref before publishing the req. Without this invariant,\n an RPC task that aborts between slot allocation and marshal\n (gss_refresh failure or signal during call_connect, for\n example) would drive xprt_release() ->\n xprt_rdma_free_slot() -> kref_put against a refcount of\n zero, saturating refcount_t and stranding the slot.\n\n - The Send-side reference is taken only after WR prep\n succeeds. A mapping failure in rpcrdma_prepare_send_sges()\n runs rpcrdma_sendctx_cancel(), which DMA-unmaps the sendctx\n and clears sc_req without touching rl_kref. The sendctx\n ring walks in rpcrdma_sendctx_put_locked() and\n rpcrdma_sendctxs_destroy() skip entries with sc_req == NULL,\n so a burst of -EIO marshal failures cannot hold reqs off\n rb_send_bufs.\n\n - The release callback re-arms rl_kref so the next consumer\n enters with the invariant satisfied.\n\nReplies now complete the RPC directly. rpcrdma_reply_handler()\ncalls rpcrdma_complete_rqst() in place of kref_put on the\nnon-LocalInv branch. The LocalInv branch already completes the\nRPC from frwr_unmap_async() and is unaffected.\n\nBecause Send-side references can now outlive RPC completion,\nconnection teardown drains sendctx entries whose unsignaled\nSends never had a later signaled completion to walk the ring.\nrpcrdma_sendctxs_destroy() walks the active range and runs\nrpcrdma_sendctx_unmap() on each entry with a non-NULL sc_req\nbefore the request buffers are reset, and is moved ahead of\nrpcrdma_reqs_reset() in rpcrdma_xprt_disconnect() so the reqs\nare still in their pre-reset state when the Send-side refs are\nreleased.\n\nThe drain creates a teardown-ordering hazard on the backchannel\npath. With the new lifetime, releasing a bc_prealloc req from\nrpcrdma_req_release() re-adds it to bc_pa_list. The disconnect\nin xprt_rdma_destroy() runs after xprt_destroy_backchannel() has\nalready emptied bc_pa_list, so the drained reqs would otherwise\nleak. xprt_rdma_destroy() now runs xprt_rdma_bc_destroy(xprt, 0)\na second time after the disconnect to reclaim them."}], "id": "CVE-2026-72473", "lastModified": "2026-08-15T06:22:21.423", "metrics": {}, "published": "2026-08-15T06:22:21.423", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/53442c7d0c888e51b8bc3da196970a669cc6b294"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/740975054a1970c0cf15f70ac39724a064f45847"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8203f760a72bd39a3b66bc4eff0aa272a99fe22b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/9f3d9b68c1c6c51746e5ecdb52b2e6a2901de37e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e7632089523acddcdd8f090ad19e96fb3107b04d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e786233d2e0bbff9a82e43f02ae3a46ab4b08ec3"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"created": "2026-08-15T12:30:07.845046+00:00", "updated": "2026-08-15T12:30:07.845051+00:00", "vendors": [], "weaknesses": ["CWE-416", "CWE-362"]}