Merge tag 'ecryptfs-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull eCryptfs updates from Tyler Hicks:

 - Hardening and fixes for maliciously crafted eCryptfs metadata in the
   lower encrypted file

 - Hardening and fixes for maliciously crafted userspace <-> kernel
   miscdev communications

 - Locking fixes for userspace <-> kernel miscdev communications

 - Fix to display encrypted filename related mount options

 - Clean up address_space_operations and reduce build dependencies by
   moving to filemap_dirty_folio()

 - Get rid of an unnecessary memory allocation in the inode update path

 - Kernel-doc formatting corrections

* tag 'ecryptfs-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  ecryptfs: ecryptfs_kernel.h: clean up kernel-doc comments
  ecryptfs: use filemap_dirty_folio for address space operations
  ecryptfs: avoid heap allocation for inode size write
  ecryptfs: show filename encryption options
  eCryptfs: bound the packet-length peek to the user buffer
  ecryptfs: reject too-small tag 70 packets
  ecryptfs: fix tag 11 packet exact-fit size check
  ecryptfs: pass packet set buffer size to parser
  ecryptfs: hold msg ctx list lock when cleaning daemon queue
  ecryptfs: release message context on send failure
  ecryptfs: reject oversized encrypted_key_size in parse_tag_3_packet

1 files changed, 3 insertions, 2 deletions

diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c
index 5a7d08149922..68804399a5df 100644
--- a/fs/ecryptfs/miscdev.c
+++ b/fs/ecryptfs/miscdev.c
@@ -360,7 +360,7 @@ ecryptfs_miscdev_write(struct file *file, const char __user *buf,
 	u32 seq;
 	size_t packet_size, packet_size_length;
 	char *data;
-	unsigned char packet_size_peek[ECRYPTFS_MAX_PKT_LEN_SIZE];
+	unsigned char packet_size_peek[ECRYPTFS_MAX_PKT_LEN_SIZE] = { };
 	ssize_t rc;
 
 	if (count == 0) {
@@ -376,7 +376,8 @@ ecryptfs_miscdev_write(struct file *file, const char __user *buf,
 	}
 
 	if (copy_from_user(packet_size_peek, &buf[PKT_LEN_OFFSET],
-			   sizeof(packet_size_peek))) {
+			   min_t(size_t, count - PKT_LEN_OFFSET,
+				 sizeof(packet_size_peek)))) {
 		printk(KERN_WARNING "%s: Error while inspecting packet size\n",
 		       __func__);
 		return -EFAULT;