From patchwork Fri Nov 10 16:07:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 13452496 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 404C1C4332F for ; Fri, 10 Nov 2023 16:09:08 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.630478.983370 (Exim 4.92) (envelope-from ) id 1r1U3y-0006ws-N0; Fri, 10 Nov 2023 16:08:54 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 630478.983370; Fri, 10 Nov 2023 16:08:54 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1r1U3y-0006wj-Ih; Fri, 10 Nov 2023 16:08:54 +0000 Received: by outflank-mailman (input) for mailman id 630478; Fri, 10 Nov 2023 16:08:53 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1r1U3x-0004cS-MI for xen-devel@lists.xenproject.org; Fri, 10 Nov 2023 16:08:53 +0000 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 709e9f67-7fe3-11ee-9b0e-b553b5be7939; Fri, 10 Nov 2023 17:08:52 +0100 (CET) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id C40FB1F8BD; Fri, 10 Nov 2023 16:08:51 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 9D4C413398; Fri, 10 Nov 2023 16:08:51 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id go4CJZNVTmWtCAAAMHmgww (envelope-from ); Fri, 10 Nov 2023 16:08:51 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 709e9f67-7fe3-11ee-9b0e-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1699632531; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yCnoHphD4HsPnyqo8Rif8MZ+KRauUhOK16PVIiar+e4=; b=j6pAGEZXlSZA9LCZF0PTqGm2Xhn+ZB9R/boeq01bE+rb6Jrmqi0Io1yMbSQzHTSGWBAJ/z 6ib3wsgqol4YKg3u+sJ0rOxCI50Dx7JnRE6tb/qkiMxTWLwYTWO26FB3ih5Dm2qq5n+l96 C8uWMzGYVpT5THx7N+cOZYS5v+ZRW3A= From: Juergen Gross To: xen-devel@lists.xenproject.org Cc: Juergen Gross , Wei Liu , Anthony PERARD Subject: [PATCH v2 08/29] tools/xenlogd: add 9pfs walk request support Date: Fri, 10 Nov 2023 17:07:43 +0100 Message-Id: <20231110160804.29021-9-jgross@suse.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20231110160804.29021-1-jgross@suse.com> References: <20231110160804.29021-1-jgross@suse.com> MIME-Version: 1.0 Add the walk request of the 9pfs protocol. Signed-off-by: Juergen Gross Reviewed-by: Jason Andryuk --- V2: - don't allow walking across symbolic links --- tools/xen-9pfsd/io.c | 172 ++++++++++++++++++++++++++++++++++++ tools/xen-9pfsd/xen-9pfsd.h | 1 + 2 files changed, 173 insertions(+) diff --git a/tools/xen-9pfsd/io.c b/tools/xen-9pfsd/io.c index 03e45d5f8b..62c64474e6 100644 --- a/tools/xen-9pfsd/io.c +++ b/tools/xen-9pfsd/io.c @@ -27,9 +27,11 @@ #define P9_CMD_VERSION 100 #define P9_CMD_ATTACH 104 #define P9_CMD_ERROR 107 +#define P9_CMD_WALK 110 #define P9_MIN_MSIZE 2048 #define P9_VERSION "9P2000.u" +#define P9_WALK_MAXELEM 16 struct p9_qid { uint8_t type; @@ -459,6 +461,21 @@ static struct p9_fid *find_fid(device *device, unsigned int fid) return NULL; } +static struct p9_fid *get_fid_ref(device *device, unsigned int fid) +{ + struct p9_fid *fidp; + + pthread_mutex_lock(&device->fid_mutex); + + fidp = find_fid(device, fid); + if ( fidp ) + fidp->ref++; + + pthread_mutex_unlock(&device->fid_mutex); + + return fidp; +} + static struct p9_fid *alloc_fid_mem(device *device, unsigned int fid, const char *path) { @@ -551,6 +568,10 @@ static int fill_qid(const char *path, struct p9_qid *qid, stbuf = &st; } + /* Don't allow symbolic links. */ + if ( S_ISLNK(stbuf->st_mode) ) + return EMLINK; + qid->type = S_ISDIR(stbuf->st_mode) ? QID_TYPE_DIR : 0; qid->version = stbuf->st_mtime ^ (stbuf->st_size << 8); qid->path = stbuf->st_ino; @@ -558,6 +579,20 @@ static int fill_qid(const char *path, struct p9_qid *qid, return 0; } +static bool name_ok(const char *str) +{ + if ( !*str ) + return false; + + if ( strchr(str, '/' ) ) + return false; + + if ( !strcmp(str, "..") || !strcmp(str, ".") ) + return false; + + return true; +} + static void p9_error(struct ring *ring, uint16_t tag, uint32_t err) { unsigned int erroff; @@ -635,6 +670,139 @@ static void p9_attach(struct ring *ring, struct p9_header *hdr) fill_buffer(ring, hdr->cmd + 1, hdr->tag, "Q", &qid); } +static void p9_walk(struct ring *ring, struct p9_header *hdr) +{ + device *device = ring->device; + uint32_t fid; + uint32_t newfid; + struct p9_fid *fidp = NULL; + struct p9_qid *qids = NULL; + unsigned int n_names = 0; + unsigned int *names = NULL; + unsigned int walked = 0; + unsigned int i; + char *path = NULL; + unsigned int path_len; + int ret; + + ret = fill_data(ring, "UUaS", &fid, &newfid, &n_names, &names); + if ( n_names > P9_WALK_MAXELEM ) + { + p9_error(ring, hdr->tag, EINVAL); + goto out; + } + if ( ret != 3 + n_names ) + { + p9_error(ring, hdr->tag, errno); + goto out; + } + + fidp = get_fid_ref(device, fid); + if ( !fidp ) + { + p9_error(ring, hdr->tag, ENOENT); + goto out; + } + if ( fidp->opened ) + { + p9_error(ring, hdr->tag, EINVAL); + goto out; + } + + path_len = strlen(fidp->path) + 1; + for ( i = 0; i < n_names; i++ ) + { + if ( !name_ok(ring->str + names[i]) ) + { + p9_error(ring, hdr->tag, ENOENT); + goto out; + } + path_len += strlen(ring->str + names[i]) + 1; + } + path = calloc(path_len + 1, 1); + if ( !path ) + { + p9_error(ring, hdr->tag, ENOMEM); + goto out; + } + strcpy(path, fidp->path); + + if ( n_names ) + { + qids = calloc(n_names, sizeof(*qids)); + if ( !qids ) + { + p9_error(ring, hdr->tag, ENOMEM); + goto out; + } + for ( i = 0; i < n_names; i++ ) + { + strcat(path, "/"); + strcat(path, ring->str + names[i]); + ret = fill_qid(path, qids + i, NULL); + if ( ret ) + { + if ( !walked ) + { + p9_error(ring, hdr->tag, errno); + goto out; + } + break; + } + walked++; + } + } + + if ( walked == n_names ) + { + const char *rel_path = path + strlen(device->host_path); + bool ok = false; + + if ( fid == newfid ) + { + struct p9_fid *new_fidp; + + pthread_mutex_lock(&device->fid_mutex); + + if ( fidp->ref != 2 ) + { + errno = EBUSY; + } + else + { + new_fidp = alloc_fid_mem(device, fid, rel_path); + if ( new_fidp ) + { + new_fidp->ref = 2; + XEN_TAILQ_REMOVE(&device->fids, fidp, list); + XEN_TAILQ_INSERT_HEAD(&device->fids, new_fidp, list); + free(fidp); + fidp = new_fidp; + ok = true; + } + } + + pthread_mutex_unlock(&device->fid_mutex); + } + else + ok = alloc_fid(device, newfid, rel_path); + + if ( !ok ) + { + p9_error(ring, hdr->tag, errno); + goto out; + } + } + + fill_buffer(ring, hdr->cmd + 1, hdr->tag, "aQ", &walked, qids); + + out: + free_fid(device, fidp); + free(qids); + free(path); + free(names); +} + void *io_thread(void *arg) { struct ring *ring = arg; @@ -698,6 +866,10 @@ void *io_thread(void *arg) p9_attach(ring, &hdr); break; + case P9_CMD_WALK: + p9_walk(ring, &hdr); + break; + default: syslog(LOG_DEBUG, "%u.%u sent unhandled command %u\n", ring->device->domid, ring->device->devid, hdr.cmd); diff --git a/tools/xen-9pfsd/xen-9pfsd.h b/tools/xen-9pfsd/xen-9pfsd.h index e511acdb76..75eaac9f7b 100644 --- a/tools/xen-9pfsd/xen-9pfsd.h +++ b/tools/xen-9pfsd/xen-9pfsd.h @@ -25,6 +25,7 @@ struct p9_fid { XEN_TAILQ_ENTRY(struct p9_fid) list; unsigned int fid; unsigned int ref; + bool opened; char path[]; };