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 2236233A029 for ; Sat, 25 Jul 2026 08:51:57 +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=1784969518; cv=none; b=mfsIcDYCNBmwGKdlHWC6fVxYUtk7syQn5E+zNKEWfPgp5mDQPbXFhmNnvzXlP4tk+krU7+/sB16AH/2NXWl+MOLMSZPqDgRA+CBfwNTK/0ccmoF5+XjOBUI8L1oM6mVOVXRubnoh5LA2imATsrWSUJf1fArm7ml25lxDTqPTX70= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784969518; c=relaxed/simple; bh=GlP+ZMZmGDYJzJSAgLpi8JW+4f1drncAcvGYkKmk6oc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=jIVeK2wFfU6ZttzkEb8C3VzmIcEDhH2DDhmVSnLasPCY2hdfzt/ZgC4Mq7E/s1VZ7MCERDjil7XCH4KXNRHQAwxnU2jr25ApTKYX1AGNYNjc7dRd5tw+jue5nJdidzF19ViJyxp3gck5iGRIgo2upcfYrwjjSBDS5HX+8YPoH18= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vmJqTRE5; 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="vmJqTRE5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 87DA31F000E9; Sat, 25 Jul 2026 08:51:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784969517; bh=Y2zvxz8kXuXWvu+HDaGW6HFJ2jmZ50I2PJoPYf/F+SE=; h=From:To:Cc:Subject:Date:Reply-To; b=vmJqTRE5mPOaWHoMCBN9wfB/3DkC33UUhChR0uFnj720E68n4eFtnLnmr5nqMUE55 jYgAjqMl9e4cNIqV2b0C6Tax+SrPm+zAenvApBJDopWjxB1VvdUyfLr/koy57m6+/I bydcYamMdbKJonzCzYAecIXDeS/qMLLrOp3Mk77Y= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-64263: fuse-uring: fix moving cancelled entry to ent_in_userspace list Date: Sat, 25 Jul 2026 10:48:00 +0200 Message-ID: <2026072558-CVE-2026-64263-971f@gregkh> X-Mailer: git-send-email 2.55.0 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=2901; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=EEBxXEoth8EWf3fuoTZHHMkYRwvRqePOc2dmXLEPNFA=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkpFXZLldpW78tfsW6uWYv2jKeHlDOuNX1j3DVlZ+Gif XmPVH32d8SyMAgyMciKKbJ82cZzdH/FIUUvQ9vTMHNYmUCGMHBxCsBE4j4xzM85/37drNwN8v3r GaJ9mXz/qU0+Ls2woElNeU3gGfnd0wyWLTVvTf4csmQtOwA= 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: fuse-uring: fix moving cancelled entry to ent_in_userspace list fuse_uring_cancel() moves entries that are available (these have no reqs attached) to the ent_in_userspace list. ent_list_request_expired() checks the first entry on ent_in_userspace and dereferences ent->fuse_req unconditionally, which will crash on a cancelled entry that was moved to this list. Fix this by freeing the entry and dropping queue_refs directly in fuse_uring_cancel(). This is safe because cancel is the cancel handler itself - after io_uring_cmd_done(), no more cancels will be dispatched for this command, and teardown serializes with cancel via queue->lock. Since cancel now decrements queue_refs, fuse_uring_abort() must no longer gate fuse_uring_abort_end_requests() on queue_refs > 0, as cancelled entries may have already dropped queue_refs while requests are still queued. Remove the gate so abort always flushes requests and stops queues. The Linux kernel CVE team has assigned CVE-2026-64263 to this issue. Affected and fixed versions =========================== Issue introduced in 6.16 with commit 4fea593e625cd50d4d11be227007849b12f17bfb and fixed in 6.18.39 with commit 50f3e03db823cabc41fe35c27d77c2bdb112baad Issue introduced in 6.16 with commit 4fea593e625cd50d4d11be227007849b12f17bfb and fixed in 7.1.4 with commit e8afc85acdf329361b2d8df2ad9b52364686235f Issue introduced in 6.16 with commit 4fea593e625cd50d4d11be227007849b12f17bfb and fixed in 7.2-rc1 with commit 198f45eeb9f78b2a2d6d8be95e4e43468eb2c6bc 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-2026-64263 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: fs/fuse/dev_uring.c fs/fuse/dev_uring_i.h 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/50f3e03db823cabc41fe35c27d77c2bdb112baad https://git.kernel.org/stable/c/e8afc85acdf329361b2d8df2ad9b52364686235f https://git.kernel.org/stable/c/198f45eeb9f78b2a2d6d8be95e4e43468eb2c6bc