From f4c697e6406da5dd445eda8d923c53e1138793dd Mon Sep 17 00:00:00 2001 From: Lukas Czerner Date: Mon, 5 Sep 2011 16:34:54 +0200 Subject: [PATCH] btrfs: return EINVAL if start > total_bytes in fitrim ioctl We should retirn EINVAL if the start is beyond the end of the file system in the btrfs_ioctl_fitrim(). Fix that by adding the appropriate check for it. Also in the btrfs_trim_fs() it is possible that len+start might overflow if big values are passed. Fix it by decrementing the len so that start+len is equal to the file system size in the worst case. Signed-off-by: Lukas Czerner --- fs/btrfs/ioctl.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index d524b6697ad9..136a2f980e21 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -282,6 +282,7 @@ static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) struct fstrim_range range; u64 minlen = ULLONG_MAX; u64 num_devices = 0; + u64 total_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy); int ret; if (!capable(CAP_SYS_ADMIN)) @@ -300,12 +301,15 @@ static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) } } rcu_read_unlock(); + if (!num_devices) return -EOPNOTSUPP; - if (copy_from_user(&range, arg, sizeof(range))) return -EFAULT; + if (range.start > total_bytes) + return -EINVAL; + range.len = min(range.len, total_bytes - range.start); range.minlen = max(range.minlen, minlen); ret = btrfs_trim_fs(root, &range); if (ret < 0)