ecryptfs fixes
memcpy() from userland pointer is a Bad Thing(tm)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c
index 6560da1..50c994a 100644
--- a/fs/ecryptfs/miscdev.c
+++ b/fs/ecryptfs/miscdev.c
@@ -243,7 +243,6 @@
struct ecryptfs_daemon *daemon;
struct ecryptfs_msg_ctx *msg_ctx;
size_t packet_length_size;
- u32 counter_nbo;
char packet_length[3];
size_t i;
size_t total_length;
@@ -328,20 +327,18 @@
"pending message\n", __func__, count, total_length);
goto out_unlock_msg_ctx;
}
- i = 0;
- buf[i++] = msg_ctx->type;
- counter_nbo = cpu_to_be32(msg_ctx->counter);
- memcpy(&buf[i], (char *)&counter_nbo, 4);
- i += 4;
+ rc = -EFAULT;
+ if (put_user(msg_ctx->type, buf))
+ goto out_unlock_msg_ctx;
+ if (put_user(cpu_to_be32(msg_ctx->counter), (__be32 __user *)(buf + 1)))
+ goto out_unlock_msg_ctx;
+ i = 5;
if (msg_ctx->msg) {
- memcpy(&buf[i], packet_length, packet_length_size);
- i += packet_length_size;
- rc = copy_to_user(&buf[i], msg_ctx->msg, msg_ctx->msg_size);
- if (rc) {
- printk(KERN_ERR "%s: copy_to_user returned error "
- "[%d]\n", __func__, rc);
+ if (copy_to_user(&buf[i], packet_length, packet_length_size))
goto out_unlock_msg_ctx;
- }
+ i += packet_length_size;
+ if (copy_to_user(&buf[i], msg_ctx->msg, msg_ctx->msg_size))
+ goto out_unlock_msg_ctx;
i += msg_ctx->msg_size;
}
rc = i;
@@ -452,7 +449,8 @@
ecryptfs_miscdev_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
- u32 counter_nbo, seq;
+ __be32 counter_nbo;
+ u32 seq;
size_t packet_size, packet_size_length, i;
ssize_t sz = 0;
char *data;
@@ -485,7 +483,7 @@
count);
goto out_free;
}
- memcpy((char *)&counter_nbo, &data[i], 4);
+ memcpy(&counter_nbo, &data[i], 4);
seq = be32_to_cpu(counter_nbo);
i += 4;
rc = ecryptfs_parse_packet_length(&data[i], &packet_size,
