From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793701290; b=5p8WS7sYCidnAAfMPFytbve5nTuPfbSYIkqvFub9JKTcGe9I5LgqYKytv8V6ipr72hMG 6S18dhY6jcYXVlYTpw3CJkGbpqF4vFmVsOPBP1zgLsHdAXwl/bGlxibgavIXFE+N2F5yD yr9loFE8J4Lcr/YBqL4JDM0bANIm2RfOlXfJwWUMd7Dt25cgL4dluP65oPVMnpXjIBiBD KCtcJH3Tv7RYHrF7OgydhD+7k0vS3Q80RRX912ZLzpd7EKprOBvnmSTkqyA2NgEiA0+9y CcxSY05cqQ+iKIkIas/keFd1xxL3XKhA4QYRNux12HMagOSt0RYLhFiW7hD2DgPoYoA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793701290; h=Received:DKIM-Signature:Subject:To:Cc:From:Date:Message-ID: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=bgVTCHKAWTAHv9byrjZQ6HwT1XBuQADjdRbyCCQEdM8=; b=DLqxtdiszrbt8Qr1VW2XW/+LBEI+3uPStBySKysDJwuZYwrCoh1xDnMYoTKCj3LGamRD wZNL0Ygp6QeKk+3mBgzoko5gfm9OcBttrSXXoP7n22br5gh252YruzHzn/BkXq/Hho9OZ dHWFcZTysEPnEoCqABC4egEEzRuYwCoqrO1pMKeD7RqpZeM2/LQAcUmfRXed7DwyDraQB 6AVj+QK5XNmidMahLmquFrQwD1TMCfsXHYRd2KKAlKdBaTbGP7qs51/38VjtHJwQkxzws fmB7pHFZF5FQE+M1y1WHpwfY0jBCT7/aZ7LmBX8GwsF4pB0pSnFdCET2fkRAOkO7hEA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=2LJTu9Eh; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6BB75606C560 for ; Tue, 3 Nov 2026 10:21:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=2LJTu9Eh Received: by smtp.kernel.org (Postfix) with ESMTPSA id ABC8F1F00A1B; Tue, 3 Nov 2026 10:21:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793701290; bh=bgVTCHKAWTAHv9byrjZQ6HwT1XBuQADjdRbyCCQEdM8=; h=Subject:To:Cc:From:Date; b=2LJTu9EhVkT90ImsA2JqsIg/1zSyRodc1A2b9/TSeqCsLYDVOSwM2aP8KNytcskyz OcyZyoWu7+AF9IHkVqKaGfQxZ76SlErcMVjiqrsIGHgpKbNhzmekCRta92BQP3CeIX 0IWRSYG660cpvF1grabKHuk5sIwOowPUeaxjGS6Q= Subject: FAILED: patch "[PATCH] ksmbd: fix invalid pointer dereference when get_inode_acl()" failed to apply to 6.1-stable tree To: huhai@kylinos.cn,chenxiaosong@kylinos.cn,linkinjeon@kernel.org Cc: From: Date: Tue, 03 Nov 2026 11:21:21 +0100 Message-ID: <2026110321-cheer-confetti-1346@gregkh> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 19d180c7baab7126af5848ed87d5f7b5add0cef2 # git commit -s git send-email --to '' --in-reply-to '2026110321-cheer-confetti-1346@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 19d180c7baab7126af5848ed87d5f7b5add0cef2 Mon Sep 17 00:00:00 2001 From: Henry Hu Date: Wed, 9 Sep 2026 11:38:54 +0800 Subject: [PATCH] ksmbd: fix invalid pointer dereference when get_inode_acl() fails When get_inode_acl() fails, it returns an ERR_PTR(), but ksmbd_acls_fattr() stored that pointer in smb_fattr without checking for errors. Later callers then passed the error pointer to security descriptor helpers or posix_acl_release(), resulting in an invalid pointer dereference. This was reproduced on an XFS-backed share when xfs_get_acl() returned ERR_PTR(-ENOMEM). Querying the SMB ACL from a CIFS client triggered the crash: BUG: unable to handle page fault for address: fffffffffffffff8 RIP: smb_acl_sec_desc_scratch_len+0x58/0x90 [ksmbd] Call Trace: smb2_query_info+0x40d/0x17c0 [ksmbd] handle_ksmbd_work+0x1ca/0x770 [ksmbd] Fix this by checking the return values from get_inode_acl() in ksmbd_acls_fattr(). Treat -EOPNOTSUPP as indicating that no ACL is available, and propagate all other errors to the callers. Update smb2_open() and smb2_get_info_sec() to handle these errors. Cc: stable@vger.kernel.org Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Assisted-by: Codex:gpt-5.6-sol Reviewed-by: ChenXiaoSong Signed-off-by: Henry Hu Signed-off-by: Namjae Jeon diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index c792ed5ebbd3..05a3388a3453 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -3647,10 +3647,11 @@ static int smb2_create_sd_buffer(struct ksmbd_work *work, le32_to_cpu(sd_buf->ccontext.DataLength), true, false); } -static void ksmbd_acls_fattr(struct smb_fattr *fattr, - const struct mnt_idmap *idmap, - struct inode *inode) +static int ksmbd_acls_fattr(struct smb_fattr *fattr, + const struct mnt_idmap *idmap, + struct inode *inode) { + struct posix_acl *acl; vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode); vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode); @@ -3661,10 +3662,28 @@ static void ksmbd_acls_fattr(struct smb_fattr *fattr, fattr->cf_dacls = NULL; if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { - fattr->cf_acls = get_inode_acl(inode, ACL_TYPE_ACCESS); - if (S_ISDIR(inode->i_mode)) - fattr->cf_dacls = get_inode_acl(inode, ACL_TYPE_DEFAULT); + acl = get_inode_acl(inode, ACL_TYPE_ACCESS); + if (IS_ERR(acl)) { + if (acl != ERR_PTR(-EOPNOTSUPP)) + return PTR_ERR(acl); + acl = NULL; + } + fattr->cf_acls = acl; + + if (S_ISDIR(inode->i_mode)) { + acl = get_inode_acl(inode, ACL_TYPE_DEFAULT); + if (IS_ERR(acl)) { + if (acl != ERR_PTR(-EOPNOTSUPP)) { + posix_acl_release(fattr->cf_acls); + return PTR_ERR(acl); + } + acl = NULL; + } + fattr->cf_dacls = acl; + } } + + return 0; } enum { @@ -4791,7 +4810,10 @@ int smb2_open(struct ksmbd_work *work) int pntsd_size; size_t scratch_len; - ksmbd_acls_fattr(&fattr, idmap, inode); + rc = ksmbd_acls_fattr(&fattr, idmap, inode); + if (rc) + goto err_out; + scratch_len = smb_acl_sec_desc_scratch_len(&fattr, NULL, 0, OWNER_SECINFO | GROUP_SECINFO | @@ -7652,7 +7674,11 @@ static int smb2_get_info_sec(struct ksmbd_work *work, idmap = file_mnt_idmap(fp->filp); inode = file_inode(fp->filp); - ksmbd_acls_fattr(&fattr, idmap, inode); + rc = ksmbd_acls_fattr(&fattr, idmap, inode); + if (rc) { + ksmbd_fd_put(work, fp); + return rc; + } if (test_share_config_flag(work->tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR))