Merge tag '9p-fixes-6.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

Pull 9p fixes from Eric Van Hensbergen:
 "Misc set of fixes for 9p.

  Most of these clean up warnings we've gotten out of compilation tools,
  but several of them were from inspection while hunting down a couple
  of regressions.

  The most important one is 75b396821cb7 ("fs/9p: remove unnecessary and
  overrestrictive check") which caused a regression for some folks by
  restricting mmap in any case where writeback caches weren't enabled.

  Most of the other bugs caught via inspection were type mismatches"

* tag '9p-fixes-6.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  fs/9p: Remove unused extern declaration
  9p: remove dead stores (variable set again without being read)
  9p: virtio: skip incrementing unused variable
  9p: virtio: make sure 'offs' is initialized in zc_request
  9p: virtio: fix unlikely null pointer deref in handle_rerror
  9p: fix ignored return value in v9fs_dir_release
  fs/9p: remove unnecessary invalidate_inode_pages2
  fs/9p: fix type mismatch in file cache mode helper
  fs/9p: fix typo in comparison logic for cache mode
  fs/9p: remove unnecessary and overrestrictive check
  fs/9p: Fix a datatype used with V9FS_DIRECT_IO

2 files changed, 16 insertions, 38 deletions

diff --git a/net/9p/client.c b/net/9p/client.c
index a3340268ec8d..86bbc7147fc1 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -904,7 +904,7 @@ EXPORT_SYMBOL(do_trace_9p_fid_put);
 
 static int p9_client_version(struct p9_client *c)
 {
-	int err = 0;
+	int err;
 	struct p9_req_t *req;
 	char *version = NULL;
 	int msize;
@@ -975,7 +975,6 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
 	struct p9_client *clnt;
 	char *client_id;
 
-	err = 0;
 	clnt = kmalloc(sizeof(*clnt), GFP_KERNEL);
 	if (!clnt)
 		return ERR_PTR(-ENOMEM);
@@ -1094,7 +1093,7 @@ struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
 				const char *uname, kuid_t n_uname,
 				const char *aname)
 {
-	int err = 0;
+	int err;
 	struct p9_req_t *req;
 	struct p9_fid *fid;
 	struct p9_qid qid;
@@ -1147,7 +1146,6 @@ struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
 	struct p9_req_t *req;
 	u16 nwqids, count;
 
-	err = 0;
 	wqids = NULL;
 	clnt = oldfid->clnt;
 	if (clone) {
@@ -1224,7 +1222,6 @@ int p9_client_open(struct p9_fid *fid, int mode)
 	clnt = fid->clnt;
 	p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
 		 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
-	err = 0;
 
 	if (fid->mode != -1)
 		return -EINVAL;
@@ -1262,7 +1259,7 @@ EXPORT_SYMBOL(p9_client_open);
 int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags,
 			  u32 mode, kgid_t gid, struct p9_qid *qid)
 {
-	int err = 0;
+	int err;
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 	int iounit;
@@ -1314,7 +1311,6 @@ int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode,
 
 	p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
 		 fid->fid, name, perm, mode);
-	err = 0;
 	clnt = fid->clnt;
 
 	if (fid->mode != -1)
@@ -1350,7 +1346,7 @@ EXPORT_SYMBOL(p9_client_fcreate);
 int p9_client_symlink(struct p9_fid *dfid, const char *name,
 		      const char *symtgt, kgid_t gid, struct p9_qid *qid)
 {
-	int err = 0;
+	int err;
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 
@@ -1402,13 +1398,12 @@ EXPORT_SYMBOL(p9_client_link);
 
 int p9_client_fsync(struct p9_fid *fid, int datasync)
 {
-	int err;
+	int err = 0;
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 
 	p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
 		 fid->fid, datasync);
-	err = 0;
 	clnt = fid->clnt;
 
 	req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
@@ -1428,7 +1423,7 @@ EXPORT_SYMBOL(p9_client_fsync);
 
 int p9_client_clunk(struct p9_fid *fid)
 {
-	int err;
+	int err = 0;
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 	int retries = 0;
@@ -1436,7 +1431,6 @@ int p9_client_clunk(struct p9_fid *fid)
 again:
 	p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n",
 		 fid->fid, retries);
-	err = 0;
 	clnt = fid->clnt;
 
 	req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
@@ -1465,12 +1459,11 @@ EXPORT_SYMBOL(p9_client_clunk);
 
 int p9_client_remove(struct p9_fid *fid)
 {
-	int err;
+	int err = 0;
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 
 	p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
-	err = 0;
 	clnt = fid->clnt;
 
 	req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
@@ -1680,7 +1673,6 @@ struct p9_wstat *p9_client_stat(struct p9_fid *fid)
 	if (!ret)
 		return ERR_PTR(-ENOMEM);
 
-	err = 0;
 	clnt = fid->clnt;
 
 	req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
@@ -1733,7 +1725,6 @@ struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
 	if (!ret)
 		return ERR_PTR(-ENOMEM);
 
-	err = 0;
 	clnt = fid->clnt;
 
 	req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
@@ -1812,11 +1803,10 @@ static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
 
 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
 {
-	int err;
+	int err = 0;
 	struct p9_req_t *req;
 	struct p9_client *clnt;
 
-	err = 0;
 	clnt = fid->clnt;
 	wst->size = p9_client_statsize(wst, clnt->proto_version);
 	p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n",
@@ -1851,11 +1841,10 @@ EXPORT_SYMBOL(p9_client_wstat);
 
 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
 {
-	int err;
+	int err = 0;
 	struct p9_req_t *req;
 	struct p9_client *clnt;
 
-	err = 0;
 	clnt = fid->clnt;
 	p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
 	p9_debug(P9_DEBUG_9P, "    valid=%x mode=%x uid=%d gid=%d size=%lld\n",
@@ -1887,7 +1876,6 @@ int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
 	struct p9_req_t *req;
 	struct p9_client *clnt;
 
-	err = 0;
 	clnt = fid->clnt;
 
 	p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
@@ -1921,11 +1909,10 @@ EXPORT_SYMBOL(p9_client_statfs);
 int p9_client_rename(struct p9_fid *fid,
 		     struct p9_fid *newdirfid, const char *name)
 {
-	int err;
+	int err = 0;
 	struct p9_req_t *req;
 	struct p9_client *clnt;
 
-	err = 0;
 	clnt = fid->clnt;
 
 	p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
@@ -1949,11 +1936,10 @@ EXPORT_SYMBOL(p9_client_rename);
 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
 		       struct p9_fid *newdirfid, const char *new_name)
 {
-	int err;
+	int err = 0;
 	struct p9_req_t *req;
 	struct p9_client *clnt;
 
-	err = 0;
 	clnt = olddirfid->clnt;
 
 	p9_debug(P9_DEBUG_9P,
@@ -1986,7 +1972,6 @@ struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
 	struct p9_client *clnt;
 	struct p9_fid *attr_fid;
 
-	err = 0;
 	clnt = file_fid->clnt;
 	attr_fid = p9_fid_create(clnt);
 	if (!attr_fid) {
@@ -2027,14 +2012,13 @@ EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
 			  u64 attr_size, int flags)
 {
-	int err;
+	int err = 0;
 	struct p9_req_t *req;
 	struct p9_client *clnt;
 
 	p9_debug(P9_DEBUG_9P,
 		 ">>> TXATTRCREATE fid %d name  %s size %llu flag %d\n",
 		 fid->fid, name, attr_size, flags);
-	err = 0;
 	clnt = fid->clnt;
 	req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
 			    fid->fid, name, attr_size, flags);
@@ -2063,7 +2047,6 @@ int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
 	p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
 		 fid->fid, offset, count);
 
-	err = 0;
 	clnt = fid->clnt;
 
 	rsize = fid->iounit;
@@ -2122,7 +2105,6 @@ int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode,
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 
-	err = 0;
 	clnt = fid->clnt;
 	p9_debug(P9_DEBUG_9P,
 		 ">>> TMKNOD fid %d name %s mode %d major %d minor %d\n",
@@ -2153,7 +2135,6 @@ int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 
-	err = 0;
 	clnt = fid->clnt;
 	p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
 		 fid->fid, name, mode, from_kgid(&init_user_ns, gid));
@@ -2182,7 +2163,6 @@ int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 
-	err = 0;
 	clnt = fid->clnt;
 	p9_debug(P9_DEBUG_9P,
 		 ">>> TLOCK fid %d type %i flags %d start %lld length %lld proc_id %d client_id %s\n",
@@ -2214,7 +2194,6 @@ int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 
-	err = 0;
 	clnt = fid->clnt;
 	p9_debug(P9_DEBUG_9P,
 		 ">>> TGETLOCK fid %d, type %i start %lld length %lld proc_id %d client_id %s\n",
@@ -2251,7 +2230,6 @@ int p9_client_readlink(struct p9_fid *fid, char **target)
 	struct p9_client *clnt;
 	struct p9_req_t *req;
 
-	err = 0;
 	clnt = fid->clnt;
 	p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
 
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index 3c27ffb781e3..e305071eb7b8 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -384,7 +384,7 @@ static void handle_rerror(struct p9_req_t *req, int in_hdr_len,
 	void *to = req->rc.sdata + in_hdr_len;
 
 	// Fits entirely into the static data?  Nothing to do.
-	if (req->rc.size < in_hdr_len)
+	if (req->rc.size < in_hdr_len || !pages)
 		return;
 
 	// Really long error message?  Tough, truncate the reply.  Might get
@@ -428,7 +428,7 @@ p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
 	struct page **in_pages = NULL, **out_pages = NULL;
 	struct virtio_chan *chan = client->trans;
 	struct scatterlist *sgs[4];
-	size_t offs;
+	size_t offs = 0;
 	int need_drop = 0;
 	int kicked = 0;
 
@@ -501,8 +501,8 @@ req_retry_pinned:
 
 	if (in_pages) {
 		sgs[out_sgs + in_sgs++] = chan->sg + out + in;
-		in += pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM,
-				     in_pages, in_nr_pages, offs, inlen);
+		pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM,
+			       in_pages, in_nr_pages, offs, inlen);
 	}
 
 	BUG_ON(out_sgs + in_sgs > ARRAY_SIZE(sgs));