From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4437B3E49C2 for ; Tue, 6 Oct 2026 10:30:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791282644; cv=none; b=IyGpeEtycw/9ZI0o9fy18LS+CqqRYIcrBsCvWK7PNds8440toG6TMgrCx/atq03Vb9m2af67P+8wJetEUAcktPSFTzjnpgcoMNDstZSUnpSv+wJRqYgAmG9MmnS3BD5n61Md/p2EvspzRo7iCpZ+DYVogXIzCggAwGJFLqcyXAs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791282644; c=relaxed/simple; bh=pu6ciQXkrnhQ5L9ncD5cWEO46IOv6Y/2jQ9AFxtUuQE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=SBKRiKbNoVTbPIwsRCMbbH5cAHUCQTSrnz8pGb8UDBF1G7kJEcy2lc01NBZv2p2IxMZg4n3FFt9PTc6lYLMfJr8guKEwV3+LuL6Ip6LA54vPpHJg9qOj2FzgY0Or4cgAtpiV/ubEuXdiYWs0L7gqkzxeqMLuiTLtijLW3h+5UAo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=TqoECD60; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="TqoECD60" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9AE1F1F000FF; Tue, 6 Oct 2026 10:30:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1791282643; bh=QeY505hlpAbU4SQVoRQkKnIwNbeiYVBqqAhoGL09xNo=; h=From:To:Cc:Subject:Date:Reply-To; b=TqoECD60mXh+6dWPnBvxRIzfWOM0V7DANSiWKkIHTgwC0Uqp8O/eks3PxIcASX9dP MaZzz1Ve6seeeG3O5Dd4fDoApKhr/PSuIy1t1m2ZRhf07sxiXnJOhFReTOzg7mY/+0 sNzwnwtGaHpAs/evDBbQms5Oe/Uspx7Z0dVILRHQ= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-98366: RDMA/rxe: validate access flags before swapping the MR's PD Date: Tue, 6 Oct 2026 10:47:47 +0200 Message-ID: <2026100622-CVE-2026-98366-e015@gregkh> X-Mailer: git-send-email 2.56.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3999; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=g1HaweIRi9bB+Ht3Ih1QNmrkH23s3pdSuWsxTPAkm6Q=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlHtiqdW3Zuh8OsmIcaJSlqcmdWVtZ+uxZRF/2u+WL07 98qsoe2d8SyMAgyMciKKbJ82cZzdH/FIUUvQ9vTMHNYmUCGMHBxCsBENl9jWHAu+pPNnr1SSRy3 F3IllLPZcKxl0maYp39IZ6en5s2aCMcEixyWdRz899d+AAA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: validate access flags before swapping the MR's PD rxe_rereg_user_mr() reassigns mr->ibmr.pd first and only then validates the IB_MR_REREG_ACCESS argument: if (flags & IB_MR_REREG_PD) { rxe_put(old_pd); rxe_get(pd); mr->ibmr.pd = ibpd; } if (flags & IB_MR_REREG_ACCESS) { if (access & ~RXE_ACCESS_SUPPORTED_MR) return ERR_PTR(-EOPNOTSUPP); mr->access = access; } Both flags pass the entry check because RXE_MR_REREG_SUPPORTED is IB_MR_REREG_PD | IB_MR_REREG_ACCESS, so a caller can reach the access check with mr->ibmr.pd already reassigned. mr->ibmr.pd is owned by the core, which adjusts pd->usecnt only on the success path: ib_uverbs_rereg_mr() jumps to put_new_uobj on a driver error without undoing the reassignment, so mr->pd == new_pd while the usecnts still charge the MR to orig_pd. ib_dereg_mr_user() then decrements new_pd, whose count can reach zero while a memory window still references it; uverbs_free_pd() frees the PD on that count alone and rxe_mw_cleanup() writes to freed memory: BUG: KASAN: slab-use-after-free in __rxe_put+0x31/0xa0 Write of size 4 at addr ffff8881301dd690 by task rxe_poc/591 __rxe_put+0x31/0xa0 rxe_mw_cleanup+0x42/0x200 __rxe_cleanup+0x115/0x370 rxe_dealloc_mw+0x4c/0x80 Allocated by task 591: ib_uverbs_alloc_pd+0x258/0x540 Freed by task 591: ib_dealloc_pd_user+0x174/0x210 uverbs_free_pd+0x8d/0xc0 ib_uverbs_dealloc_pd+0x18e/0x1d0 Validate the access flags before mutating any state so the callback either applies every requested change or none. The Linux kernel CVE team has assigned CVE-2026-98366 to this issue. Affected and fixed versions =========================== Issue introduced in 6.5 with commit 544c7f62cf32db2bd358f1e8a40a98bf98fa2a5c and fixed in 6.6.158 with commit 08f12745cb72981aa2cabe214af0c7a42a856f0a Issue introduced in 6.5 with commit 544c7f62cf32db2bd358f1e8a40a98bf98fa2a5c and fixed in 6.12.112 with commit 7230cc456d4bb2221c20c5f1d22b38b8576aa16f Issue introduced in 6.5 with commit 544c7f62cf32db2bd358f1e8a40a98bf98fa2a5c and fixed in 6.18.54 with commit fe602c91a52e161ace4afd5bdb8f33270c554c6f Issue introduced in 6.5 with commit 544c7f62cf32db2bd358f1e8a40a98bf98fa2a5c and fixed in 7.2.8 with commit 4dd7a53f1c5b44693c26dac4b9b5bd5bb9d604c8 Issue introduced in 6.5 with commit 544c7f62cf32db2bd358f1e8a40a98bf98fa2a5c and fixed in 7.3-rc4 with commit ae36a5b609ae79f4de966328b78d2584be9719a4 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-98366 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: drivers/infiniband/sw/rxe/rxe_verbs.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/08f12745cb72981aa2cabe214af0c7a42a856f0a https://git.kernel.org/stable/c/7230cc456d4bb2221c20c5f1d22b38b8576aa16f https://git.kernel.org/stable/c/fe602c91a52e161ace4afd5bdb8f33270c554c6f https://git.kernel.org/stable/c/4dd7a53f1c5b44693c26dac4b9b5bd5bb9d604c8 https://git.kernel.org/stable/c/ae36a5b609ae79f4de966328b78d2584be9719a4