This is a note to let you know that I've just added the patch titled
btrfs: validate qgroup inherit for SNAP_CREATE_V2 ioctl
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
btrfs-validate-qgroup-inherit-for-snap_create_v2-ioctl.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 5011c5a663b9c6d6aff3d394f11049b371199627 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dancarpenter@xxxxxxxxxx>
Date: Wed, 17 Feb 2021 09:04:34 +0300
Subject: btrfs: validate qgroup inherit for SNAP_CREATE_V2 ioctl
From: Dan Carpenter <dancarpenter@xxxxxxxxxx>
commit 5011c5a663b9c6d6aff3d394f11049b371199627 upstream.
The problem is we're copying "inherit" from user space but we don't
necessarily know that we're copying enough data for a 64 byte
struct. Then the next problem is that 'inherit' has a variable size
array at the end, and we have to verify that array is the size we
expected.
Fixes: 6f72c7e20dba ("Btrfs: add qgroup inheritance")
CC: stable@xxxxxxxxxxxxxxx # 4.4+
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/ioctl.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1842,7 +1842,10 @@ static noinline int btrfs_ioctl_snap_cre
if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
readonly = true;
if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
- if (vol_args->size > PAGE_SIZE) {
+ u64 nums;
+
+ if (vol_args->size < sizeof(*inherit) ||
+ vol_args->size > PAGE_SIZE) {
ret = -EINVAL;
goto free_args;
}
@@ -1851,6 +1854,20 @@ static noinline int btrfs_ioctl_snap_cre
ret = PTR_ERR(inherit);
goto free_args;
}
+
+ if (inherit->num_qgroups > PAGE_SIZE ||
+ inherit->num_ref_copies > PAGE_SIZE ||
+ inherit->num_excl_copies > PAGE_SIZE) {
+ ret = -EINVAL;
+ goto free_inherit;
+ }
+
+ nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
+ 2 * inherit->num_excl_copies;
+ if (vol_args->size != struct_size(inherit, qgroups, nums)) {
+ ret = -EINVAL;
+ goto free_inherit;
+ }
}
ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
Patches currently in stable-queue which might be from dancarpenter@xxxxxxxxxx are
queue-4.19/btrfs-validate-qgroup-inherit-for-snap_create_v2-ioctl.patch
