From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 2D6BD7BAF4; Mon, 8 Apr 2024 13:32:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712583169; cv=none; b=q1yq+nRAdD0nMSzLSGD3yGyxoEnrG2jeTWW/wyc798kGYheDob+lTevTdedoE9kTTXFVRpRs3bg02HkhrrKrG3TkFSB+lBAbIl7GUHFiQd7o5TtcnnwO8t5AL0B4cuLAMXXbDW1d85Ry8YbYvAYmzYkTuNJ4CH9ddeh6xnBDIXo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712583169; c=relaxed/simple; bh=bNgZzs6wNhN+imbfsKuwae8BN/0Bq4+GZnlL9XNSdCo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Qq5ZkfAsKspA4C3VUY+SyodOmbxx2vUW1PKJaTx5wUKC6nIhowofo3j4J7n8I2vP8nQBgmBodbY6GSqbRZt17GUDe9VmMHpftAkyEKV4C5bkGF0eL7w8SoXDm9ABm6/HndMHRHhzxvjNoij3FOdsH+up2SIK8GiQBo9UK9GH5MI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=B85uK6oe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="B85uK6oe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 72B41C433C7; Mon, 8 Apr 2024 13:32:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712583168; bh=bNgZzs6wNhN+imbfsKuwae8BN/0Bq4+GZnlL9XNSdCo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B85uK6oegOSIsRckO/Mq3sr7j0V4IzE/CHqr7F8qoJHmmmG2UlDQCWm/pqUDxnbaV y3xcWEdpF6D2fISYLs1lpxJCwIzjqyJqgpa4f3pjPPfKOiKyvGAC3BIJrVPQ5JUK3x tMhBz9zj4LBaXHLvrOQ8JNZQ0z7PjjlpAlsXH3/U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Amir Goldstein , Jan Kara , Chuck Lever Subject: [PATCH 5.15 218/690] fanotify: use helpers to parcel fanotify_info buffer Date: Mon, 8 Apr 2024 14:51:24 +0200 Message-ID: <20240408125407.447621560@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125359.506372836@linuxfoundation.org> References: <20240408125359.506372836@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Amir Goldstein [ Upstream commit 1a9515ac9e55e68d733bab81bd408463ab1e25b1 ] fanotify_info buffer is parceled into variable sized records, so the records must be written in order: dir_fh, file_fh, name. Use helpers to assert that order and make fanotify_alloc_name_event() a bit more generic to allow empty dir_fh record and to allow expanding to more records (i.e. name2) soon. Link: https://lore.kernel.org/r/20211129201537.1932819-7-amir73il@gmail.com Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara Signed-off-by: Chuck Lever --- fs/notify/fanotify/fanotify.c | 35 +++++++++++++++++++---------------- fs/notify/fanotify/fanotify.h | 20 ++++++++++++++++++++ 2 files changed, 39 insertions(+), 16 deletions(-) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index ffad224be0149..2b13c79cebc62 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -576,7 +576,7 @@ static struct fanotify_event *fanotify_alloc_fid_event(struct inode *id, return &ffe->fae; } -static struct fanotify_event *fanotify_alloc_name_event(struct inode *id, +static struct fanotify_event *fanotify_alloc_name_event(struct inode *dir, __kernel_fsid_t *fsid, const struct qstr *name, struct inode *child, @@ -586,15 +586,17 @@ static struct fanotify_event *fanotify_alloc_name_event(struct inode *id, struct fanotify_name_event *fne; struct fanotify_info *info; struct fanotify_fh *dfh, *ffh; - unsigned int dir_fh_len = fanotify_encode_fh_len(id); + unsigned int dir_fh_len = fanotify_encode_fh_len(dir); unsigned int child_fh_len = fanotify_encode_fh_len(child); - unsigned int size; + unsigned long name_len = name ? name->len : 0; + unsigned int len, size; - size = sizeof(*fne) + FANOTIFY_FH_HDR_LEN + dir_fh_len; + /* Reserve terminating null byte even for empty name */ + size = sizeof(*fne) + name_len + 1; + if (dir_fh_len) + size += FANOTIFY_FH_HDR_LEN + dir_fh_len; if (child_fh_len) size += FANOTIFY_FH_HDR_LEN + child_fh_len; - if (name) - size += name->len + 1; fne = kmalloc(size, gfp); if (!fne) return NULL; @@ -604,22 +606,23 @@ static struct fanotify_event *fanotify_alloc_name_event(struct inode *id, *hash ^= fanotify_hash_fsid(fsid); info = &fne->info; fanotify_info_init(info); - dfh = fanotify_info_dir_fh(info); - info->dir_fh_totlen = fanotify_encode_fh(dfh, id, dir_fh_len, hash, 0); + if (dir_fh_len) { + dfh = fanotify_info_dir_fh(info); + len = fanotify_encode_fh(dfh, dir, dir_fh_len, hash, 0); + fanotify_info_set_dir_fh(info, len); + } if (child_fh_len) { ffh = fanotify_info_file_fh(info); - info->file_fh_totlen = fanotify_encode_fh(ffh, child, - child_fh_len, hash, 0); + len = fanotify_encode_fh(ffh, child, child_fh_len, hash, 0); + fanotify_info_set_file_fh(info, len); } - if (name) { - long salt = name->len; - + if (name_len) { fanotify_info_copy_name(info, name); - *hash ^= full_name_hash((void *)salt, name->name, name->len); + *hash ^= full_name_hash((void *)name_len, name->name, name_len); } - pr_debug("%s: ino=%lu size=%u dir_fh_len=%u child_fh_len=%u name_len=%u name='%.*s'\n", - __func__, id->i_ino, size, dir_fh_len, child_fh_len, + pr_debug("%s: size=%u dir_fh_len=%u child_fh_len=%u name_len=%u name='%.*s'\n", + __func__, size, dir_fh_len, child_fh_len, info->name_len, info->name_len, fanotify_info_name(info)); return &fne->fae; diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index dd23ba659e76b..7ac6f9f1e4148 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -138,6 +138,26 @@ static inline void fanotify_info_init(struct fanotify_info *info) info->name_len = 0; } +/* These set/copy helpers MUST be called by order */ +static inline void fanotify_info_set_dir_fh(struct fanotify_info *info, + unsigned int totlen) +{ + if (WARN_ON_ONCE(info->file_fh_totlen > 0) || + WARN_ON_ONCE(info->name_len > 0)) + return; + + info->dir_fh_totlen = totlen; +} + +static inline void fanotify_info_set_file_fh(struct fanotify_info *info, + unsigned int totlen) +{ + if (WARN_ON_ONCE(info->name_len > 0)) + return; + + info->file_fh_totlen = totlen; +} + static inline void fanotify_info_copy_name(struct fanotify_info *info, const struct qstr *name) { -- 2.43.0