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=1793701289; b=OOmxSfFd6z3mySmFDED1OjQ3/DfDcixqWfHkaJeee64XD1tGqH2zE3qiMWgWwp8Gs421 YOlxf4uVOWAk8M6QmrfppUnE3Jht2RkcZh5hPncxQCs51rwdTA2D+nBpBhXToNnaorKRC I07U1VOSUfIaSuE+0AjnuHtorjdmIOaKkTM6gwOw1zQsuetGw6lbC4Q3JSsS25bA0MyIi aJHznAu9q3eVSCLwDlNA/uwjuoPHkkfIuXxfXhe6Jd7S2fqHzsvx/plPBlFtGyovRO6Zi dr5hAOQQvnEr3zYtxkmDL/NOBVUry7rhf1PHZLKi7yAIWZHDLfawYvodp6+DdeKy/xg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793701289; h=Received:DKIM-Signature:Subject:To:Cc:From:Date:Message-ID: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=QEv0llRfdeZZXYDD9SsVns34NrPdv/zR8LIuHjqm7dE=; b=UqMq/iSJaUYK0UnpmsKFhAotqVYH5Y2oJ6gf4cBqr3yZvRq4ZAGmc8H1FO54ed6rO5+A SRKZqXAIYtm0AG8Xcn7n9fH0FHDanmgJrZoDcAlep0hztn8cmA03IKH01ZifKlOUQJGzy WRqXq6Tk0UVcyFS302rB21s15sj/F1hdcui3QxdVGA/1qypdVw5bpnzmH4EECVu6hrrJ5 JEL0xMdjFglif+EWrAqha77h3soSh641tTy0gX9S141rulDWwhMKTL7nGmSCQbDnYkdRh HmkGdAInsQYPN2UTuOA0yQslD8ajiwLbEnXALipbslv6E6kVw9hCApuM5EBTODLz63w== 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=aR6MO2DH; 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 D5CF1606A820 for ; Tue, 3 Nov 2026 10:21:28 +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=aR6MO2DH Received: by smtp.kernel.org (Postfix) with ESMTPSA id 202181F000C1; Tue, 3 Nov 2026 10:21:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793701288; bh=QEv0llRfdeZZXYDD9SsVns34NrPdv/zR8LIuHjqm7dE=; h=Subject:To:Cc:From:Date; b=aR6MO2DH0tB4Dn2+PdismoD1hU5kp0kcT5V/4hDuEeg1fvvFsk19OfryXsbu8/QNS JSRNpdzuSioHLEzoWB7+DxPk+vkrsI2giz/CGxAwmTElU+qTN8YiikpmbOn1l+NkYp ToQtzP4AbbU8/TlqnFfCq3Z4QTQhKYMpTVNHy3UM= Subject: FAILED: patch "[PATCH] ksmbd: fix invalid pointer dereference when get_inode_acl()" failed to apply to 5.15-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-overstuff-recoil-e280@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 5.15-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-5.15.y git checkout FETCH_HEAD git cherry-pick -x 19d180c7baab7126af5848ed87d5f7b5add0cef2 # git commit -s git send-email --to '' --in-reply-to '2026110321-overstuff-recoil-e280@gregkh' --subject-prefix 'PATCH 5.15.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))