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 5076558F078 for ; Fri, 11 Sep 2026 20:02:20 +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=1789156950; cv=none; b=XiAuIsJSCZk9wMGUL4zukum+Hhsarfgot8uhXhu4EpZ5yfoTnQLS0seqLvFI2UYIOswWV9lSpMSrMN9hpCtnZcwj348olvSdfNwicPTqiBTXWwiu2QUpwQ34sx92F1rxamRl8tj3KQCK66XU/IjsNxroUTwqCYyI8qt24rIqH6g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156950; c=relaxed/simple; bh=tu9c+tZZeGfXywTDrUiXHBX4X2p0QZ+AJcGM7tQrPXg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=EQ8voXZ/x6VMzyqidnkkHkYVkyj6RBnc11fJMwGq9PPzdz7F4uTzZ8p2UkbEHvFvW1/R2253D+qQyRN0sbO/xPHCc8tfULfKdHo2gwafn3WmbHG0YIA7IWayH6EjBQ+XnWJvPynFsyr2VGabaecOR20QaYO4z1nO4yP7D/FkctY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=xQkpNmG8; 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="xQkpNmG8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B7D21F00898; Fri, 11 Sep 2026 20:02:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156939; bh=fhrm2qRZ0kUPT4SJSaj+/YrplCNo1727PkI1uD5Ymaw=; h=From:To:Cc:Subject:Date:Reply-To; b=xQkpNmG8KZMO/PpHt1vA5FbQ79TLKL8NNw/cniYwlJRZCKVGuBpDd2LGyEI35zsPS ppRVotOvzVpg77JI1APFkwDaBqHkq0IZserQfvvyMG2N7bqv1s/ENyOgyVNheg9TYp SW9sF2IFZdYNyzl8WSKl7rhxh6xoz16oIxE0b810= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89683: nfsd: fix dentry ref leak on V4ROOT export filehandle lookup Date: Fri, 11 Sep 2026 21:46:12 +0200 Message-ID: <2026091151-CVE-2026-89683-7584@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=2608; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=k+b4gWCjcZadAqDyZLAaodXm3pG++2j4LFwHuDvijQk=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIuut419dvvC0+Hf3yaT/f2Tfvzupt6/o9Ud+m4AeE Vm/TJm0jlgWBkEmBlkxRZYv23iO7q84pOhlaHsaZg4rE8gQBi5OAZjIHX2GBUv2ru72EGpV6tRJ +vvWYOs2lZdsGQwLJkh9KVniNjFy7aIr+g2Xe6xC9705BAA= 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: nfsd: fix dentry ref leak on V4ROOT export filehandle lookup nfsd_set_fh_dentry() leaks the dentry reference from exportfs_decode_fh_raw() when the NFS3_FHSIZE or NFS_FHSIZE switch cases detect NFSEXP_V4ROOT and goto out. The out: label calls exp_put() but never dput(dentry), and fhp->fh_dentry was never assigned so fh_put() cannot compensate. A crafted NFSv3 filehandle targeting a V4ROOT export's fsid triggers the leak on every request. The Linux kernel CVE team has assigned CVE-2026-89683 to this issue. Affected and fixed versions =========================== Issue introduced in 6.12 with commit ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 and fixed in 6.12.109 with commit d493cf57f4c4dae5396cd6ad41e5c209d0615a81 Issue introduced in 6.12 with commit ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 and fixed in 6.18.50 with commit c1ae0f973bcba5730871e35976a0ab6878fdac34 Issue introduced in 6.12 with commit ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 and fixed in 7.2.4 with commit 11db8df188b34bdb8c6a3a0bf438e5fc8cd75aca Issue introduced in 6.12 with commit ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 and fixed in 7.3-rc1 with commit 6247023fbbec1325029f2d5f2a7cdc0f9f9ea15a 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-2026-89683 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/nfsd/nfsfh.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/d493cf57f4c4dae5396cd6ad41e5c209d0615a81 https://git.kernel.org/stable/c/c1ae0f973bcba5730871e35976a0ab6878fdac34 https://git.kernel.org/stable/c/11db8df188b34bdb8c6a3a0bf438e5fc8cd75aca https://git.kernel.org/stable/c/6247023fbbec1325029f2d5f2a7cdc0f9f9ea15a