build: Bump serde_json from 1.0.114 to 1.0.115 in /fuzz

Bumps [serde_json](https://github.com/serde-rs/json) from 1.0.114 to 1.0.115.
- [Release notes](https://github.com/serde-rs/json/releases)
- [Commits](https://github.com/serde-rs/json/compare/v1.0.114...v1.0.115)

---
updated-dependencies:
- dependency-name: serde_json
  dependency-type: indirect
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

fuzz/Cargo.lock

@@ -720,9 +720,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.114"
+version = "1.0.115"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c5f09b1bd632ef549eaa9f60a1f8de742bdbc698e6cee2095fc84dde5f549ae0"
+checksum = "12dc5c46daa8e9fdf4f5e71b6cf9a53f2487da0e86e55808e2d35539666497dd"
 dependencies = [
  "itoa",
  "ryu",

virtio-devices/src/vhost_user/fs.rs

@@ -271,17 +271,18 @@ impl VhostUserFrontendReqHandler for BackendReqHandler {
     }
 }
 
+pub const VIRTIO_FS_TAG_LEN: usize = 36;
 #[derive(Copy, Clone, Versionize)]
 #[repr(C, packed)]
 pub struct VirtioFsConfig {
-    pub tag: [u8; 36],
+    pub tag: [u8; VIRTIO_FS_TAG_LEN],
     pub num_request_queues: u32,
 }
 
 impl Default for VirtioFsConfig {
     fn default() -> Self {
         VirtioFsConfig {
-            tag: [0; 36],
+            tag: [0; VIRTIO_FS_TAG_LEN],
             num_request_queues: 0,
         }
     }
@@ -397,8 +398,13 @@ impl Fs {
 
             // Create virtio-fs device configuration.
             let mut config = VirtioFsConfig::default();
-            let tag_bytes_vec = tag.to_string().into_bytes();
+            let tag_bytes_slice = tag.as_bytes();
-            config.tag[..tag_bytes_vec.len()].copy_from_slice(tag_bytes_vec.as_slice());
+            let len = if tag_bytes_slice.len() < config.tag.len() {
+                tag_bytes_slice.len()
+            } else {
+                config.tag.len()
+            };
+            config.tag[..len].copy_from_slice(tag_bytes_slice[..len].as_ref());
             config.num_request_queues = req_num_queues as u32;
 
             (

vmm/src/config.rs

@@ -24,6 +24,8 @@ const MAX_NUM_PCI_SEGMENTS: u16 = 96;
 pub enum Error {
     /// Filesystem tag is missing
     ParseFsTagMissing,
+    /// Filesystem tag is too long
+    ParseFsTagTooLong,
     /// Filesystem socket is missing
     ParseFsSockMissing,
     /// Missing persistent memory file parameter.
@@ -355,6 +357,11 @@ impl fmt::Display for Error {
             ParseFileSystem(o) => write!(f, "Error parsing --fs: {o}"),
             ParseFsSockMissing => write!(f, "Error parsing --fs: socket missing"),
             ParseFsTagMissing => write!(f, "Error parsing --fs: tag missing"),
+            ParseFsTagTooLong => write!(
+                f,
+                "Error parsing --fs: max tag length is {}",
+                virtio_devices::vhost_user::VIRTIO_FS_TAG_LEN
+            ),
             ParsePersistentMemory(o) => write!(f, "Error parsing --pmem: {o}"),
             ParsePmemFileMissing => write!(f, "Error parsing --pmem: file missing"),
             ParseVsock(o) => write!(f, "Error parsing --vsock: {o}"),
@@ -1519,6 +1526,9 @@ impl FsConfig {
         parser.parse(fs).map_err(Error::ParseFileSystem)?;
 
         let tag = parser.get("tag").ok_or(Error::ParseFsTagMissing)?;
+        if tag.len() > virtio_devices::vhost_user::VIRTIO_FS_TAG_LEN {
+            return Err(Error::ParseFsTagTooLong);
+        }
         let socket = PathBuf::from(parser.get("socket").ok_or(Error::ParseFsSockMissing)?);
 
         let queue_size = parser