From c47ca32d3aadb234f73389a34c97574085bc9eda Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 4 Sep 2014 14:09:15 +0300 Subject: Btrfs: kfree()ing ERR_PTRs The "inherit" in btrfs_ioctl_snap_create_v2() and "vol_args" in btrfs_ioctl_rm_dev() are ERR_PTRs so we can't call kfree() on them. These kind of bugs are "One Err Bugs" where there is just one error label that does everything. I could set the "inherit = NULL" and keep the single out label but it ends up being more complicated that way. It makes the code simpler to re-order the unwind so it's in the mirror order of the allocation and introduce some new error labels. Signed-off-by: Dan Carpenter Signed-off-by: Chris Mason --- fs/btrfs/ioctl.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) (limited to 'fs') diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index a018ea484d39..8a8e29878c34 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1703,7 +1703,7 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | BTRFS_SUBVOL_QGROUP_INHERIT)) { ret = -EOPNOTSUPP; - goto out; + goto free_args; } if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) @@ -1713,27 +1713,31 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { if (vol_args->size > PAGE_CACHE_SIZE) { ret = -EINVAL; - goto out; + goto free_args; } inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); if (IS_ERR(inherit)) { ret = PTR_ERR(inherit); - goto out; + goto free_args; } } ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, vol_args->fd, subvol, ptr, readonly, inherit); + if (ret) + goto free_inherit; - if (ret == 0 && ptr && - copy_to_user(arg + - offsetof(struct btrfs_ioctl_vol_args_v2, - transid), ptr, sizeof(*ptr))) + if (ptr && copy_to_user(arg + + offsetof(struct btrfs_ioctl_vol_args_v2, + transid), + ptr, sizeof(*ptr))) ret = -EFAULT; -out: - kfree(vol_args); + +free_inherit: kfree(inherit); +free_args: + kfree(vol_args); return ret; } @@ -2653,7 +2657,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) { ret = PTR_ERR(vol_args); - goto out; + goto err_drop; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; @@ -2671,6 +2675,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) out: kfree(vol_args); +err_drop: mnt_drop_write_file(file); return ret; } -- cgit v1.2.3