1 files changed, 150 insertions, 24 deletions

diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 99e44ea7d875..fd48e8d37f2e 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -7,6 +7,7 @@
 */
 
 #include "fuse_i.h"
+#include "dev_uring_i.h"
 
 #include <linux/pagemap.h>
 #include <linux/slab.h>
@@ -35,6 +36,11 @@ DEFINE_MUTEX(fuse_mutex);
 
 static int set_global_limit(const char *val, const struct kernel_param *kp);
 
+unsigned int fuse_max_pages_limit = 256;
+/* default is no timeout */
+unsigned int fuse_default_req_timeout;
+unsigned int fuse_max_req_timeout;
+
 unsigned max_user_bgreq;
 module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
 		  &max_user_bgreq, 0644);
@@ -173,6 +179,14 @@ static void fuse_evict_inode(struct inode *inode)
 			fuse_cleanup_submount_lookup(fc, fi->submount_lookup);
 			fi->submount_lookup = NULL;
 		}
+		/*
+		 * Evict of non-deleted inode may race with outstanding
+		 * LOOKUP/READDIRPLUS requests and result in inconsistency when
+		 * the request finishes.  Deal with that here by bumping a
+		 * counter that can be compared to the starting value.
+		 */
+		if (inode->i_nlink > 0)
+			atomic64_inc(&fc->evict_ctr);
 	}
 	if (S_ISREG(inode->i_mode) && !fuse_is_bad(inode)) {
 		WARN_ON(fi->iocachectr != 0);
@@ -206,17 +220,30 @@ static ino_t fuse_squash_ino(u64 ino64)
 
 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
 				   struct fuse_statx *sx,
-				   u64 attr_valid, u32 cache_mask)
+				   u64 attr_valid, u32 cache_mask,
+				   u64 evict_ctr)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	struct fuse_inode *fi = get_fuse_inode(inode);
 
 	lockdep_assert_held(&fi->lock);
 
+	/*
+	 * Clear basic stats from invalid mask.
+	 *
+	 * Don't do this if this is coming from a fuse_iget() call and there
+	 * might have been a racing evict which would've invalidated the result
+	 * if the attr_version would've been preserved.
+	 *
+	 * !evict_ctr -> this is create
+	 * fi->attr_version != 0 -> this is not a new inode
+	 * evict_ctr == fuse_get_evict_ctr() -> no evicts while during request
+	 */
+	if (!evict_ctr || fi->attr_version || evict_ctr == fuse_get_evict_ctr(fc))
+		set_mask_bits(&fi->inval_mask, STATX_BASIC_STATS, 0);
+
 	fi->attr_version = atomic64_inc_return(&fc->attr_version);
 	fi->i_time = attr_valid;
-	/* Clear basic stats from invalid mask */
-	set_mask_bits(&fi->inval_mask, STATX_BASIC_STATS, 0);
 
 	inode->i_ino     = fuse_squash_ino(attr->ino);
 	inode->i_mode    = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
@@ -295,9 +322,9 @@ u32 fuse_get_cache_mask(struct inode *inode)
 	return STATX_MTIME | STATX_CTIME | STATX_SIZE;
 }
 
-void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
-			    struct fuse_statx *sx,
-			    u64 attr_valid, u64 attr_version)
+static void fuse_change_attributes_i(struct inode *inode, struct fuse_attr *attr,
+				     struct fuse_statx *sx, u64 attr_valid,
+				     u64 attr_version, u64 evict_ctr)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	struct fuse_inode *fi = get_fuse_inode(inode);
@@ -331,7 +358,8 @@ void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
 	}
 
 	old_mtime = inode_get_mtime(inode);
-	fuse_change_attributes_common(inode, attr, sx, attr_valid, cache_mask);
+	fuse_change_attributes_common(inode, attr, sx, attr_valid, cache_mask,
+				      evict_ctr);
 
 	oldsize = inode->i_size;
 	/*
@@ -372,6 +400,13 @@ void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
 		fuse_dax_dontcache(inode, attr->flags);
 }
 
+void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
+			    struct fuse_statx *sx, u64 attr_valid,
+			    u64 attr_version)
+{
+	fuse_change_attributes_i(inode, attr, sx, attr_valid, attr_version, 0);
+}
+
 static void fuse_init_submount_lookup(struct fuse_submount_lookup *sl,
 				      u64 nodeid)
 {
@@ -426,7 +461,8 @@ static int fuse_inode_set(struct inode *inode, void *_nodeidp)
 
 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
 			int generation, struct fuse_attr *attr,
-			u64 attr_valid, u64 attr_version)
+			u64 attr_valid, u64 attr_version,
+			u64 evict_ctr)
 {
 	struct inode *inode;
 	struct fuse_inode *fi;
@@ -487,8 +523,8 @@ retry:
 	fi->nlookup++;
 	spin_unlock(&fi->lock);
 done:
-	fuse_change_attributes(inode, attr, NULL, attr_valid, attr_version);
-
+	fuse_change_attributes_i(inode, attr, NULL, attr_valid, attr_version,
+				 evict_ctr);
 	return inode;
 }
 
@@ -740,8 +776,8 @@ static const struct fs_parameter_spec fuse_fs_parameters[] = {
 	fsparam_string	("source",		OPT_SOURCE),
 	fsparam_u32	("fd",			OPT_FD),
 	fsparam_u32oct	("rootmode",		OPT_ROOTMODE),
-	fsparam_u32	("user_id",		OPT_USER_ID),
-	fsparam_u32	("group_id",		OPT_GROUP_ID),
+	fsparam_uid	("user_id",		OPT_USER_ID),
+	fsparam_gid	("group_id",		OPT_GROUP_ID),
 	fsparam_flag	("default_permissions",	OPT_DEFAULT_PERMISSIONS),
 	fsparam_flag	("allow_other",		OPT_ALLOW_OTHER),
 	fsparam_u32	("max_read",		OPT_MAX_READ),
@@ -755,6 +791,8 @@ static int fuse_parse_param(struct fs_context *fsc, struct fs_parameter *param)
 	struct fs_parse_result result;
 	struct fuse_fs_context *ctx = fsc->fs_private;
 	int opt;
+	kuid_t kuid;
+	kgid_t kgid;
 
 	if (fsc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
 		/*
@@ -799,16 +837,26 @@ static int fuse_parse_param(struct fs_context *fsc, struct fs_parameter *param)
 		break;
 
 	case OPT_USER_ID:
-		ctx->user_id = make_kuid(fsc->user_ns, result.uint_32);
-		if (!uid_valid(ctx->user_id))
+		kuid = result.uid;
+		/*
+		 * The requested uid must be representable in the
+		 * filesystem's idmapping.
+		 */
+		if (!kuid_has_mapping(fsc->user_ns, kuid))
 			return invalfc(fsc, "Invalid user_id");
+		ctx->user_id = kuid;
 		ctx->user_id_present = true;
 		break;
 
 	case OPT_GROUP_ID:
-		ctx->group_id = make_kgid(fsc->user_ns, result.uint_32);
-		if (!gid_valid(ctx->group_id))
+		kgid = result.gid;
+		/*
+		 * The requested gid must be representable in the
+		 * filesystem's idmapping.
+		 */
+		if (!kgid_has_mapping(fsc->user_ns, kgid))
 			return invalfc(fsc, "Invalid group_id");
+		ctx->group_id = kgid;
 		ctx->group_id_present = true;
 		break;
 
@@ -893,7 +941,7 @@ static void fuse_iqueue_init(struct fuse_iqueue *fiq,
 	fiq->priv = priv;
 }
 
-static void fuse_pqueue_init(struct fuse_pqueue *fpq)
+void fuse_pqueue_init(struct fuse_pqueue *fpq)
 {
 	unsigned int i;
 
@@ -928,11 +976,14 @@ void fuse_conn_init(struct fuse_conn *fc, struct fuse_mount *fm,
 	fc->initialized = 0;
 	fc->connected = 1;
 	atomic64_set(&fc->attr_version, 1);
+	atomic64_set(&fc->evict_ctr, 1);
 	get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
 	fc->pid_ns = get_pid_ns(task_active_pid_ns(current));
 	fc->user_ns = get_user_ns(user_ns);
 	fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ;
-	fc->max_pages_limit = FUSE_MAX_MAX_PAGES;
+	fc->max_pages_limit = fuse_max_pages_limit;
+	fc->name_max = FUSE_NAME_LOW_MAX;
+	fc->timeout.req_timeout = 0;
 
 	if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH))
 		fuse_backing_files_init(fc);
@@ -947,6 +998,8 @@ static void delayed_release(struct rcu_head *p)
 {
 	struct fuse_conn *fc = container_of(p, struct fuse_conn, rcu);
 
+	fuse_uring_destruct(fc);
+
 	put_user_ns(fc->user_ns);
 	fc->release(fc);
 }
@@ -959,6 +1012,8 @@ void fuse_conn_put(struct fuse_conn *fc)
 
 		if (IS_ENABLED(CONFIG_FUSE_DAX))
 			fuse_dax_conn_free(fc);
+		if (fc->timeout.req_timeout)
+			cancel_delayed_work_sync(&fc->timeout.work);
 		if (fiq->ops->release)
 			fiq->ops->release(fiq);
 		put_pid_ns(fc->pid_ns);
@@ -989,7 +1044,7 @@ static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
 	attr.mode = mode;
 	attr.ino = FUSE_ROOT_ID;
 	attr.nlink = 1;
-	return fuse_iget(sb, FUSE_ROOT_ID, 0, &attr, 0, 0);
+	return fuse_iget(sb, FUSE_ROOT_ID, 0, &attr, 0, 0, 0);
 }
 
 struct fuse_inode_handle {
@@ -1209,6 +1264,34 @@ static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg)
 	spin_unlock(&fc->bg_lock);
 }
 
+static void set_request_timeout(struct fuse_conn *fc, unsigned int timeout)
+{
+	fc->timeout.req_timeout = secs_to_jiffies(timeout);
+	INIT_DELAYED_WORK(&fc->timeout.work, fuse_check_timeout);
+	queue_delayed_work(system_wq, &fc->timeout.work,
+			   fuse_timeout_timer_freq);
+}
+
+static void init_server_timeout(struct fuse_conn *fc, unsigned int timeout)
+{
+	if (!timeout && !fuse_max_req_timeout && !fuse_default_req_timeout)
+		return;
+
+	if (!timeout)
+		timeout = fuse_default_req_timeout;
+
+	if (fuse_max_req_timeout) {
+		if (timeout)
+			timeout = min(fuse_max_req_timeout, timeout);
+		else
+			timeout = fuse_max_req_timeout;
+	}
+
+	timeout = max(FUSE_TIMEOUT_TIMER_FREQ, timeout);
+
+	set_request_timeout(fc, timeout);
+}
+
 struct fuse_init_args {
 	struct fuse_args args;
 	struct fuse_init_in in;
@@ -1227,6 +1310,7 @@ static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args,
 		ok = false;
 	else {
 		unsigned long ra_pages;
+		unsigned int timeout = 0;
 
 		process_init_limits(fc, arg);
 
@@ -1290,6 +1374,13 @@ static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args,
 				fc->max_pages =
 					min_t(unsigned int, fc->max_pages_limit,
 					max_t(unsigned int, arg->max_pages, 1));
+
+				/*
+				 * PATH_MAX file names might need two pages for
+				 * ops like rename
+				 */
+				if (fc->max_pages > 1)
+					fc->name_max = FUSE_NAME_MAX;
 			}
 			if (IS_ENABLED(CONFIG_FUSE_DAX)) {
 				if (flags & FUSE_MAP_ALIGNMENT &&
@@ -1320,23 +1411,41 @@ static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args,
 			 * on a stacked fs (e.g. overlayfs) themselves and with
 			 * max_stack_depth == 1, FUSE fs can be stacked as the
 			 * underlying fs of a stacked fs (e.g. overlayfs).
+			 *
+			 * Also don't allow the combination of FUSE_PASSTHROUGH
+			 * and FUSE_WRITEBACK_CACHE, current design doesn't handle
+			 * them together.
 			 */
 			if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH) &&
 			    (flags & FUSE_PASSTHROUGH) &&
 			    arg->max_stack_depth > 0 &&
-			    arg->max_stack_depth <= FILESYSTEM_MAX_STACK_DEPTH) {
+			    arg->max_stack_depth <= FILESYSTEM_MAX_STACK_DEPTH &&
+			    !(flags & FUSE_WRITEBACK_CACHE))  {
 				fc->passthrough = 1;
 				fc->max_stack_depth = arg->max_stack_depth;
 				fm->sb->s_stack_depth = arg->max_stack_depth;
 			}
 			if (flags & FUSE_NO_EXPORT_SUPPORT)
 				fm->sb->s_export_op = &fuse_export_fid_operations;
+			if (flags & FUSE_ALLOW_IDMAP) {
+				if (fc->default_permissions)
+					fm->sb->s_iflags &= ~SB_I_NOIDMAP;
+				else
+					ok = false;
+			}
+			if (flags & FUSE_OVER_IO_URING && fuse_uring_enabled())
+				fc->io_uring = 1;
+
+			if (flags & FUSE_REQUEST_TIMEOUT)
+				timeout = arg->request_timeout;
 		} else {
 			ra_pages = fc->max_read / PAGE_SIZE;
 			fc->no_lock = 1;
 			fc->no_flock = 1;
 		}
 
+		init_server_timeout(fc, timeout);
+
 		fm->sb->s_bdi->ra_pages =
 				min(fm->sb->s_bdi->ra_pages, ra_pages);
 		fc->minor = arg->minor;
@@ -1378,7 +1487,8 @@ void fuse_send_init(struct fuse_mount *fm)
 		FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT | FUSE_INIT_EXT |
 		FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP |
 		FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_ALLOW_MMAP |
-		FUSE_NO_EXPORT_SUPPORT | FUSE_HAS_RESEND;
+		FUSE_NO_EXPORT_SUPPORT | FUSE_HAS_RESEND | FUSE_ALLOW_IDMAP |
+		FUSE_REQUEST_TIMEOUT;
 #ifdef CONFIG_FUSE_DAX
 	if (fm->fc->dax)
 		flags |= FUSE_MAP_ALIGNMENT;
@@ -1390,6 +1500,13 @@ void fuse_send_init(struct fuse_mount *fm)
 	if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH))
 		flags |= FUSE_PASSTHROUGH;
 
+	/*
+	 * This is just an information flag for fuse server. No need to check
+	 * the reply - server is either sending IORING_OP_URING_CMD or not.
+	 */
+	if (fuse_uring_enabled())
+		flags |= FUSE_OVER_IO_URING;
+
 	ia->in.flags = flags;
 	ia->in.flags2 = flags >> 32;
 
@@ -1555,6 +1672,7 @@ static void fuse_sb_defaults(struct super_block *sb)
 	sb->s_time_gran = 1;
 	sb->s_export_op = &fuse_export_operations;
 	sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE;
+	sb->s_iflags |= SB_I_NOIDMAP;
 	if (sb->s_user_ns != &init_user_ns)
 		sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER;
 	sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION);
@@ -1586,7 +1704,8 @@ static int fuse_fill_super_submount(struct super_block *sb,
 		return -ENOMEM;
 
 	fuse_fill_attr_from_inode(&root_attr, parent_fi);
-	root = fuse_iget(sb, parent_fi->nodeid, 0, &root_attr, 0, 0);
+	root = fuse_iget(sb, parent_fi->nodeid, 0, &root_attr, 0, 0,
+			 fuse_get_evict_ctr(fm->fc));
 	/*
 	 * This inode is just a duplicate, so it is not looked up and
 	 * its nlookup should not be incremented.  fuse_iget() does
@@ -1967,7 +2086,7 @@ static void fuse_kill_sb_anon(struct super_block *sb)
 static struct file_system_type fuse_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "fuse",
-	.fs_flags	= FS_HAS_SUBTYPE | FS_USERNS_MOUNT,
+	.fs_flags	= FS_HAS_SUBTYPE | FS_USERNS_MOUNT | FS_ALLOW_IDMAP,
 	.init_fs_context = fuse_init_fs_context,
 	.parameters	= fuse_fs_parameters,
 	.kill_sb	= fuse_kill_sb_anon,
@@ -1988,7 +2107,7 @@ static struct file_system_type fuseblk_fs_type = {
 	.init_fs_context = fuse_init_fs_context,
 	.parameters	= fuse_fs_parameters,
 	.kill_sb	= fuse_kill_sb_blk,
-	.fs_flags	= FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
+	.fs_flags	= FS_REQUIRES_DEV | FS_HAS_SUBTYPE | FS_ALLOW_IDMAP,
 };
 MODULE_ALIAS_FS("fuseblk");
 
@@ -2039,8 +2158,14 @@ static int __init fuse_fs_init(void)
 	if (err)
 		goto out3;
 
+	err = fuse_sysctl_register();
+	if (err)
+		goto out4;
+
 	return 0;
 
+ out4:
+	unregister_filesystem(&fuse_fs_type);
  out3:
 	unregister_fuseblk();
  out2:
@@ -2051,6 +2176,7 @@ static int __init fuse_fs_init(void)
 
 static void fuse_fs_cleanup(void)
 {
+	fuse_sysctl_unregister();
 	unregister_filesystem(&fuse_fs_type);
 	unregister_fuseblk();