btrfs: fix send ioctl on 32bit with 64bit kernel
We pass in a pointer in our send arg struct, this means the struct size
doesn't match with 32bit user space and 64bit kernel space. Fix this by
adding a compat mode and doing the appropriate conversion.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ move structure to the beginning, next to receive 32bit compat ]
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 0746eda..d9ddcdb 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -26,6 +26,7 @@
#include <linux/radix-tree.h>
#include <linux/vmalloc.h>
#include <linux/string.h>
+#include <linux/compat.h>
#include "send.h"
#include "backref.h"
@@ -6371,13 +6372,12 @@ static void btrfs_root_dec_send_in_progress(struct btrfs_root* root)
spin_unlock(&root->root_item_lock);
}
-long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_)
+long btrfs_ioctl_send(struct file *mnt_file, struct btrfs_ioctl_send_args *arg)
{
int ret = 0;
struct btrfs_root *send_root = BTRFS_I(file_inode(mnt_file))->root;
struct btrfs_fs_info *fs_info = send_root->fs_info;
struct btrfs_root *clone_root;
- struct btrfs_ioctl_send_args *arg = NULL;
struct btrfs_key key;
struct send_ctx *sctx = NULL;
u32 i;
@@ -6413,13 +6413,6 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_)
goto out;
}
- arg = memdup_user(arg_, sizeof(*arg));
- if (IS_ERR(arg)) {
- ret = PTR_ERR(arg);
- arg = NULL;
- goto out;
- }
-
/*
* Check that we don't overflow at later allocations, we request
* clone_sources_count + 1 items, and compare to unsigned long inside
@@ -6660,7 +6653,6 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_)
if (sctx && !IS_ERR_OR_NULL(sctx->parent_root))
btrfs_root_dec_send_in_progress(sctx->parent_root);
- kfree(arg);
kvfree(clone_sources_tmp);
if (sctx) {
