ceph: convert int fields in ceph_mount_options to unsigned int

Most of these values should never be negative, so convert them to
unsigned values. Add some sanity checking to the parsed values, and
clean up some unneeded casts.

Note that while caps_max should never be negative, this patch leaves
it signed, since this value ends up later being compared to a signed
counter. Just ensure that userland never passes in a negative value
for caps_max.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

3 files changed, 26 insertions, 23 deletions

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 068b029cf073..a3110d216aae 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2032,12 +2032,13 @@ int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
 	struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
 	struct ceph_mount_options *opt = req->r_mdsc->fsc->mount_options;
 	size_t size = sizeof(struct ceph_mds_reply_dir_entry);
-	int order, num_entries;
+	unsigned int num_entries;
+	int order;
 
 	spin_lock(&ci->i_ceph_lock);
 	num_entries = ci->i_files + ci->i_subdirs;
 	spin_unlock(&ci->i_ceph_lock);
-	num_entries = max(num_entries, 1);
+	num_entries = max(num_entries, 1U);
 	num_entries = min(num_entries, opt->max_readdir);
 
 	order = get_order(size * num_entries);
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index 9c9a7c68eea3..29a795f975df 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -172,10 +172,10 @@ static const struct fs_parameter_enum ceph_mount_param_enums[] = {
 static const struct fs_parameter_spec ceph_mount_param_specs[] = {
 	fsparam_flag_no ("acl",				Opt_acl),
 	fsparam_flag_no ("asyncreaddir",		Opt_asyncreaddir),
-	fsparam_u32	("caps_max",			Opt_caps_max),
+	fsparam_s32	("caps_max",			Opt_caps_max),
 	fsparam_u32	("caps_wanted_delay_max",	Opt_caps_wanted_delay_max),
 	fsparam_u32	("caps_wanted_delay_min",	Opt_caps_wanted_delay_min),
-	fsparam_s32	("write_congestion_kb",		Opt_congestion_kb),
+	fsparam_u32	("write_congestion_kb",		Opt_congestion_kb),
 	fsparam_flag_no ("copyfrom",			Opt_copyfrom),
 	fsparam_flag_no ("dcache",			Opt_dcache),
 	fsparam_flag_no ("dirstat",			Opt_dirstat),
@@ -187,8 +187,8 @@ static const struct fs_parameter_spec ceph_mount_param_specs[] = {
 	fsparam_flag_no ("quotadf",			Opt_quotadf),
 	fsparam_u32	("rasize",			Opt_rasize),
 	fsparam_flag_no ("rbytes",			Opt_rbytes),
-	fsparam_s32	("readdir_max_bytes",		Opt_readdir_max_bytes),
-	fsparam_s32	("readdir_max_entries",		Opt_readdir_max_entries),
+	fsparam_u32	("readdir_max_bytes",		Opt_readdir_max_bytes),
+	fsparam_u32	("readdir_max_entries",		Opt_readdir_max_entries),
 	fsparam_enum	("recover_session",		Opt_recover_session),
 	fsparam_flag_no ("require_active_mds",		Opt_require_active_mds),
 	fsparam_u32	("rsize",			Opt_rsize),
@@ -328,7 +328,9 @@ static int ceph_parse_mount_param(struct fs_context *fc,
 		fsopt->caps_wanted_delay_max = result.uint_32;
 		break;
 	case Opt_caps_max:
-		fsopt->caps_max = result.uint_32;
+		if (result.int_32 < 0)
+			goto out_of_range;
+		fsopt->caps_max = result.int_32;
 		break;
 	case Opt_readdir_max_entries:
 		if (result.uint_32 < 1)
@@ -547,25 +549,25 @@ static int ceph_show_options(struct seq_file *m, struct dentry *root)
 		seq_show_option(m, "recover_session", "clean");
 
 	if (fsopt->wsize != CEPH_MAX_WRITE_SIZE)
-		seq_printf(m, ",wsize=%d", fsopt->wsize);
+		seq_printf(m, ",wsize=%u", fsopt->wsize);
 	if (fsopt->rsize != CEPH_MAX_READ_SIZE)
-		seq_printf(m, ",rsize=%d", fsopt->rsize);
+		seq_printf(m, ",rsize=%u", fsopt->rsize);
 	if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
-		seq_printf(m, ",rasize=%d", fsopt->rasize);
+		seq_printf(m, ",rasize=%u", fsopt->rasize);
 	if (fsopt->congestion_kb != default_congestion_kb())
-		seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
+		seq_printf(m, ",write_congestion_kb=%u", fsopt->congestion_kb);
 	if (fsopt->caps_max)
 		seq_printf(m, ",caps_max=%d", fsopt->caps_max);
 	if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
-		seq_printf(m, ",caps_wanted_delay_min=%d",
+		seq_printf(m, ",caps_wanted_delay_min=%u",
 			 fsopt->caps_wanted_delay_min);
 	if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
-		seq_printf(m, ",caps_wanted_delay_max=%d",
+		seq_printf(m, ",caps_wanted_delay_max=%u",
 			   fsopt->caps_wanted_delay_max);
 	if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
-		seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
+		seq_printf(m, ",readdir_max_entries=%u", fsopt->max_readdir);
 	if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
-		seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
+		seq_printf(m, ",readdir_max_bytes=%u", fsopt->max_readdir_bytes);
 	if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
 		seq_show_option(m, "snapdirname", fsopt->snapdir_name);
 
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index f0f9cb7447ac..3bf1a01cd536 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -73,16 +73,16 @@
 #define CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT     60  /* cap release delay */
 
 struct ceph_mount_options {
-	int flags;
+	unsigned int flags;
 
-	int wsize;            /* max write size */
-	int rsize;            /* max read size */
-	int rasize;           /* max readahead */
-	int congestion_kb;    /* max writeback in flight */
-	int caps_wanted_delay_min, caps_wanted_delay_max;
+	unsigned int wsize;            /* max write size */
+	unsigned int rsize;            /* max read size */
+	unsigned int rasize;           /* max readahead */
+	unsigned int congestion_kb;    /* max writeback in flight */
+	unsigned int caps_wanted_delay_min, caps_wanted_delay_max;
 	int caps_max;
-	int max_readdir;       /* max readdir result (entires) */
-	int max_readdir_bytes; /* max readdir result (bytes) */
+	unsigned int max_readdir;       /* max readdir result (entries) */
+	unsigned int max_readdir_bytes; /* max readdir result (bytes) */
 
 	/*
 	 * everything above this point can be memcmp'd; everything below