Add locking around modifver and connver

2 files changed, 23 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index 66ca1e2..4c6ba2d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,8 @@
 	* Fix double free if reconnection races with request sending.
 	Patch by E. Kuemmerle
 
+	* Add locking around modifver and connver
+
 2011-10-21  Miklos Szeredi <miklos@szeredi.hu>
 
 	* Remove "-oPreferredAuthentications" from ssh options if the
diff --git a/sshfs.c b/sshfs.c
index 109d266..632bb1c 100644
--- a/sshfs.c
+++ b/sshfs.c
@@ -2144,12 +2144,19 @@ static int sshfs_chown(const char *path, uid_t uid, gid_t gid)
 static int sshfs_truncate_workaround(const char *path, off_t size,
                                      struct fuse_file_info *fi);
 
+static void sshfs_inc_modifver(void)
+{
+	pthread_mutex_lock(&sshfs.lock);
+	sshfs.modifver++;
+	pthread_mutex_unlock(&sshfs.lock);
+}
+
 static int sshfs_truncate(const char *path, off_t size)
 {
 	int err;
 	struct buffer buf;
 
-	sshfs.modifver ++;
+	sshfs_inc_modifver();
 	if (size == 0 || sshfs.truncate_workaround)
 		return sshfs_truncate_workaround(path, size, NULL);
 
@@ -2178,7 +2185,13 @@ static int sshfs_utime(const char *path, struct utimbuf *ubuf)
 
 static inline int sshfs_file_is_conn(struct sshfs_file *sf)
 {
-	return sf->connver == sshfs.connver;
+	int ret;
+
+	pthread_mutex_lock(&sshfs.lock);
+	ret = (sf->connver == sshfs.connver);
+	pthread_mutex_unlock(&sshfs.lock);
+
+	return ret;
 }
 
 static int sshfs_open_common(const char *path, mode_t mode,
@@ -2221,8 +2234,10 @@ static int sshfs_open_common(const char *path, mode_t mode,
 	sf->is_seq = 0;
 	sf->refs = 1;
 	sf->next_pos = 0;
+	pthread_mutex_lock(&sshfs.lock);
 	sf->modifver= sshfs.modifver;
 	sf->connver = sshfs.connver;
+	pthread_mutex_unlock(&sshfs.lock);
 	buf_init(&buf, 0);
 	buf_add_path(&buf, path);
 	buf_add_uint32(&buf, pflags);
@@ -2430,7 +2445,9 @@ static void submit_read(struct sshfs_file *sf, size_t size, off_t offset,
 	chunk->offset = offset;
 	chunk->size = size;
 	chunk->refs = 1;
+	pthread_mutex_lock(&sshfs.lock);	
 	chunk->modifver = sshfs.modifver;
+	pthread_mutex_unlock(&sshfs.lock);	
 	sshfs_send_async_read(sf, chunk);
 	pthread_mutex_lock(&sshfs.lock);
 	chunk_put(*chunkp);
@@ -2573,7 +2590,7 @@ static int sshfs_write(const char *path, const char *wbuf, size_t size,
 	if (!sshfs_file_is_conn(sf))
 		return -EIO;
 
-	sshfs.modifver ++;
+	sshfs_inc_modifver();
 	buf_init(&buf, 0);
 	buf_add_buf(&buf, handle);
 	buf_add_uint64(&buf, offset);
@@ -2679,7 +2696,7 @@ static int sshfs_ftruncate(const char *path, off_t size,
 	if (!sshfs_file_is_conn(sf))
 		return -EIO;
 
-	sshfs.modifver ++;
+	sshfs_inc_modifver();
 	if (sshfs.truncate_workaround)
 		return sshfs_truncate_workaround(path, size, fi);