In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Refactor DMCUB enter/exit idle interface
[Why]
We can hang in place trying to send commands when the DMCUB isn't
powered on.
[How]
We need to exit out of the idle state prior to sending a command,
but the process that performs the exit also invokes a command itself.
Fixing this issue involves the following:
1. Using a software state to track whether or not we need to start
the process to exit idle or notify idle.
It's possible for the hardware to have exited an idle state without
driver knowledge, but entering one is always restricted to a driver
allow - which makes the SW state vs HW state mismatch issue purely one
of optimization, which should seldomly be hit, if at all.
2. Refactor any instances of exit/notify idle to use a single wrapper
that maintains this SW state.
This works simialr to dc_allow_idle_optimizations, but works at the
DMCUB level and makes sure the state is marked prior to any notify/exit
idle so we don't enter an infinite loop.
3. Make sure we exit out of idle prior to sending any commands or
waiting for DMCUB idle.
This patch takes care of 1/2. A future patch will take care of wrapping
DMCUB command submission with calls to this new interface.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Wake DMCUB before executing GPINT commands
[Why]
DMCUB can be in idle when we attempt to interface with the HW through
the GPINT mailbox resulting in a system hang.
[How]
Add dc_wake_and_execute_gpint() to wrap the wake, execute, sleep
sequence.
If the GPINT executes successfully then DMCUB will be put back into
sleep after the optional response is returned.
It functions similar to the inbox command interface.
In the Linux kernel, the following vulnerability has been resolved:
sysctl: Fix out of bounds access for empty sysctl registers
When registering tables to the sysctl subsystem there is a check to see
if header is a permanently empty directory (used for mounts). This check
evaluates the first element of the ctl_table. This results in an out of
bounds evaluation when registering empty directories.
The function register_sysctl_mount_point now passes a ctl_table of size
1 instead of size 0. It now relies solely on the type to identify
a permanently empty register.
Make sure that the ctl_table has at least one element before testing for
permanent emptiness.
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: Avoid touching renamed directory if parent does not change
The VFS will not be locking moved directory if its parent does not
change. Change ocfs2 rename code to avoid touching renamed directory if
its parent does not change as without locking that can corrupt the
filesystem.
In the Linux kernel, the following vulnerability has been resolved:
reiserfs: Avoid touching renamed directory if parent does not change
The VFS will not be locking moved directory if its parent does not
change. Change reiserfs rename code to avoid touching renamed directory
if its parent does not change as without locking that can corrupt the
filesystem.
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix possible NULL dereference in amdgpu_ras_query_error_status_helper()
Return invalid error code -EINVAL for invalid block id.
Fixes the below:
drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:1183 amdgpu_ras_query_error_status_helper() error: we previously assumed 'info' could be null (see line 1176)
In the Linux kernel, the following vulnerability has been resolved:
drm/msm/dpu: Add mutex lock in control vblank irq
Add a mutex lock to control vblank irq to synchronize vblank
enable/disable operations happening from different threads to prevent
race conditions while registering/unregistering the vblank irq callback.
v4: -Removed vblank_ctl_lock from dpu_encoder_virt, so it is only a
parameter of dpu_encoder_phys.
-Switch from atomic refcnt to a simple int counter as mutex has
now been added
v3: Mistakenly did not change wording in last version. It is done now.
v2: Slightly changed wording of commit message
Patchwork: https://patchwork.freedesktop.org/patch/571854/
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Wake DMCUB before sending a command
[Why]
We can hang in place trying to send commands when the DMCUB isn't
powered on.
[How]
For functions that execute within a DC context or DC lock we can
wrap the direct calls to dm_execute_dmub_cmd/list with code that
exits idle power optimizations and reallows once we're done with
the command submission on success.
For DM direct submissions the DM will need to manage the enter/exit
sequencing manually.
We cannot invoke a DMCUB command directly within the DM execution
helper or we can deadlock.
In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_acl_tcam: Fix NULL pointer dereference in error path
When calling mlxsw_sp_acl_tcam_region_destroy() from an error path after
failing to attach the region to an ACL group, we hit a NULL pointer
dereference upon 'region->group->tcam' [1].
Fix by retrieving the 'tcam' pointer using mlxsw_sp_acl_to_tcam().
[1]
BUG: kernel NULL pointer dereference, address: 0000000000000000
[...]
RIP: 0010:mlxsw_sp_acl_tcam_region_destroy+0xa0/0xd0
[...]
Call Trace:
mlxsw_sp_acl_tcam_vchunk_get+0x88b/0xa20
mlxsw_sp_acl_tcam_ventry_add+0x25/0xe0
mlxsw_sp_acl_rule_add+0x47/0x240
mlxsw_sp_flower_replace+0x1a9/0x1d0
tc_setup_cb_add+0xdc/0x1c0
fl_hw_replace_filter+0x146/0x1f0
fl_change+0xc17/0x1360
tc_new_tfilter+0x472/0xb90
rtnetlink_rcv_msg+0x313/0x3b0
netlink_rcv_skb+0x58/0x100
netlink_unicast+0x244/0x390
netlink_sendmsg+0x1e4/0x440
____sys_sendmsg+0x164/0x260
___sys_sendmsg+0x9a/0xe0
__sys_sendmsg+0x7a/0xc0
do_syscall_64+0x40/0xe0
entry_SYSCALL_64_after_hwframe+0x63/0x6b
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: fix netdev_priv() dereference before check on non-DSA netdevice events
After the blamed commit, we started doing this dereference for every
NETDEV_CHANGEUPPER and NETDEV_PRECHANGEUPPER event in the system.
static inline struct dsa_port *dsa_user_to_port(const struct net_device *dev)
{
struct dsa_user_priv *p = netdev_priv(dev);
return p->dp;
}
Which is obviously bogus, because not all net_devices have a netdev_priv()
of type struct dsa_user_priv. But struct dsa_user_priv is fairly small,
and p->dp means dereferencing 8 bytes starting with offset 16. Most
drivers allocate that much private memory anyway, making our access not
fault, and we discard the bogus data quickly afterwards, so this wasn't
caught.
But the dummy interface is somewhat special in that it calls
alloc_netdev() with a priv size of 0. So every netdev_priv() dereference
is invalid, and we get this when we emit a NETDEV_PRECHANGEUPPER event
with a VLAN as its new upper:
$ ip link add dummy1 type dummy
$ ip link add link dummy1 name dummy1.100 type vlan id 100
[ 43.309174] ==================================================================
[ 43.316456] BUG: KASAN: slab-out-of-bounds in dsa_user_prechangeupper+0x30/0xe8
[ 43.323835] Read of size 8 at addr ffff3f86481d2990 by task ip/374
[ 43.330058]
[ 43.342436] Call trace:
[ 43.366542] dsa_user_prechangeupper+0x30/0xe8
[ 43.371024] dsa_user_netdevice_event+0xb38/0xee8
[ 43.375768] notifier_call_chain+0xa4/0x210
[ 43.379985] raw_notifier_call_chain+0x24/0x38
[ 43.384464] __netdev_upper_dev_link+0x3ec/0x5d8
[ 43.389120] netdev_upper_dev_link+0x70/0xa8
[ 43.393424] register_vlan_dev+0x1bc/0x310
[ 43.397554] vlan_newlink+0x210/0x248
[ 43.401247] rtnl_newlink+0x9fc/0xe30
[ 43.404942] rtnetlink_rcv_msg+0x378/0x580
Avoid the kernel oops by dereferencing after the type check, as customary.