In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix slab-use-after-free Read in rxe_queue_cleanup bug
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x7d/0xa0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xcf/0x610 mm/kasan/report.c:489
kasan_report+0xb5/0xe0 mm/kasan/report.c:602
rxe_queue_cleanup+0xd0/0xe0 drivers/infiniband/sw/rxe/rxe_queue.c:195
rxe_cq_cleanup+0x3f/0x50 drivers/infiniband/sw/rxe/rxe_cq.c:132
__rxe_cleanup+0x168/0x300 drivers/infiniband/sw/rxe/rxe_pool.c:232
rxe_create_cq+0x22e/0x3a0 drivers/infiniband/sw/rxe/rxe_verbs.c:1109
create_cq+0x658/0xb90 drivers/infiniband/core/uverbs_cmd.c:1052
ib_uverbs_create_cq+0xc7/0x120 drivers/infiniband/core/uverbs_cmd.c:1095
ib_uverbs_write+0x969/0xc90 drivers/infiniband/core/uverbs_main.c:679
vfs_write fs/read_write.c:677 [inline]
vfs_write+0x26a/0xcc0 fs/read_write.c:659
ksys_write+0x1b8/0x200 fs/read_write.c:731
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xaa/0x1b0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
In the function rxe_create_cq, when rxe_cq_from_init fails, the function
rxe_cleanup will be called to handle the allocated resources. In fact,
some memory resources have already been freed in the function
rxe_cq_from_init. Thus, this problem will occur.
The solution is to let rxe_cleanup do all the work.
In the Linux kernel, the following vulnerability has been resolved:
regulator: max20086: fix invalid memory access
max20086_parse_regulators_dt() calls of_regulator_match() using an
array of struct of_regulator_match allocated on the stack for the
matches argument.
of_regulator_match() calls devm_of_regulator_put_matches(), which calls
devres_alloc() to allocate a struct devm_of_regulator_matches which will
be de-allocated using devm_of_regulator_put_matches().
struct devm_of_regulator_matches is populated with the stack allocated
matches array.
If the device fails to probe, devm_of_regulator_put_matches() will be
called and will try to call of_node_put() on that stack pointer,
generating the following dmesg entries:
max20086 6-0028: Failed to read DEVICE_ID reg: -121
kobject: '\xc0$\xa5\x03' (000000002cebcb7a): is not initialized, yet
kobject_put() is being called.
Followed by a stack trace matching the call flow described above.
Switch to allocating the matches array using devm_kcalloc() to
avoid accessing the stack pointer long after it's out of scope.
This also has the advantage of allowing multiple max20086 to probe
without overriding the data stored inside the global of_regulator_match.
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: idxd: fix memory leak in error handling path of idxd_alloc
Memory allocated for idxd is not freed if an error occurs during
idxd_alloc(). To fix it, free the allocated memory in the reverse order
of allocation before exiting the function in case of an error.
In the Linux kernel, the following vulnerability has been resolved:
net/tls: fix kernel panic when alloc_page failed
We cannot set frag_list to NULL pointer when alloc_page failed.
It will be used in tls_strp_check_queue_ok when the next time
tls_strp_read_sock is called.
This is because we don't reset full_len in tls_strp_flush_anchor_copy()
so the recv path will try to continue handling the partial record
on the next call but we dettached the rcvq from the frag list.
Alternative fix would be to reset full_len.
Unable to handle kernel NULL pointer dereference
at virtual address 0000000000000028
Call trace:
tls_strp_check_rcv+0x128/0x27c
tls_strp_data_ready+0x34/0x44
tls_data_ready+0x3c/0x1f0
tcp_data_ready+0x9c/0xe4
tcp_data_queue+0xf6c/0x12d0
tcp_rcv_established+0x52c/0x798
In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_router: Fix use-after-free when deleting GRE net devices
The driver only offloads neighbors that are constructed on top of net
devices registered by it or their uppers (which are all Ethernet). The
device supports GRE encapsulation and decapsulation of forwarded
traffic, but the driver will not offload dummy neighbors constructed on
top of GRE net devices as they are not uppers of its net devices:
# ip link add name gre1 up type gre tos inherit local 192.0.2.1 remote 198.51.100.1
# ip neigh add 0.0.0.0 lladdr 0.0.0.0 nud noarp dev gre1
$ ip neigh show dev gre1 nud noarp
0.0.0.0 lladdr 0.0.0.0 NOARP
(Note that the neighbor is not marked with 'offload')
When the driver is reloaded and the existing configuration is replayed,
the driver does not perform the same check regarding existing neighbors
and offloads the previously added one:
# devlink dev reload pci/0000:01:00.0
$ ip neigh show dev gre1 nud noarp
0.0.0.0 lladdr 0.0.0.0 offload NOARP
If the neighbor is later deleted, the driver will ignore the
notification (given the GRE net device is not its upper) and will
therefore keep referencing freed memory, resulting in a use-after-free
[1] when the net device is deleted:
# ip neigh del 0.0.0.0 lladdr 0.0.0.0 dev gre1
# ip link del dev gre1
Fix by skipping neighbor replay if the net device for which the replay
is performed is not our upper.
[1]
BUG: KASAN: slab-use-after-free in mlxsw_sp_neigh_entry_update+0x1ea/0x200
Read of size 8 at addr ffff888155b0e420 by task ip/2282
[...]
Call Trace:
<TASK>
dump_stack_lvl+0x6f/0xa0
print_address_description.constprop.0+0x6f/0x350
print_report+0x108/0x205
kasan_report+0xdf/0x110
mlxsw_sp_neigh_entry_update+0x1ea/0x200
mlxsw_sp_router_rif_gone_sync+0x2a8/0x440
mlxsw_sp_rif_destroy+0x1e9/0x750
mlxsw_sp_netdevice_ipip_ol_event+0x3c9/0xdc0
mlxsw_sp_router_netdevice_event+0x3ac/0x15e0
notifier_call_chain+0xca/0x150
call_netdevice_notifiers_info+0x7f/0x100
unregister_netdevice_many_notify+0xc8c/0x1d90
rtnl_dellink+0x34e/0xa50
rtnetlink_rcv_msg+0x6fb/0xb70
netlink_rcv_skb+0x131/0x360
netlink_unicast+0x426/0x710
netlink_sendmsg+0x75a/0xc20
__sock_sendmsg+0xc1/0x150
____sys_sendmsg+0x5aa/0x7b0
___sys_sendmsg+0xfc/0x180
__sys_sendmsg+0x121/0x1b0
do_syscall_64+0xbb/0x1d0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
In the Linux kernel, the following vulnerability has been resolved:
RDMA/core: Fix "KASAN: slab-use-after-free Read in ib_register_device" problem
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc3/0x670 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
strlen+0x93/0xa0 lib/string.c:420
__fortify_strlen include/linux/fortify-string.h:268 [inline]
get_kobj_path_length lib/kobject.c:118 [inline]
kobject_get_path+0x3f/0x2a0 lib/kobject.c:158
kobject_uevent_env+0x289/0x1870 lib/kobject_uevent.c:545
ib_register_device drivers/infiniband/core/device.c:1472 [inline]
ib_register_device+0x8cf/0xe00 drivers/infiniband/core/device.c:1393
rxe_register_device+0x275/0x320 drivers/infiniband/sw/rxe/rxe_verbs.c:1552
rxe_net_add+0x8e/0xe0 drivers/infiniband/sw/rxe/rxe_net.c:550
rxe_newlink+0x70/0x190 drivers/infiniband/sw/rxe/rxe.c:225
nldev_newlink+0x3a3/0x680 drivers/infiniband/core/nldev.c:1796
rdma_nl_rcv_msg+0x387/0x6e0 drivers/infiniband/core/netlink.c:195
rdma_nl_rcv_skb.constprop.0.isra.0+0x2e5/0x450
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg net/socket.c:727 [inline]
____sys_sendmsg+0xa95/0xc70 net/socket.c:2566
___sys_sendmsg+0x134/0x1d0 net/socket.c:2620
__sys_sendmsg+0x16d/0x220 net/socket.c:2652
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
This problem is similar to the problem that the
commit 1d6a9e7449e2 ("RDMA/core: Fix use-after-free when rename device name")
fixes.
The root cause is: the function ib_device_rename() renames the name with
lock. But in the function kobject_uevent(), this name is accessed without
lock protection at the same time.
The solution is to add the lock protection when this name is accessed in
the function kobject_uevent().
In the Linux kernel, the following vulnerability has been resolved:
mm/page_alloc: fix race condition in unaccepted memory handling
The page allocator tracks the number of zones that have unaccepted memory
using static_branch_enc/dec() and uses that static branch in hot paths to
determine if it needs to deal with unaccepted memory.
Borislav and Thomas pointed out that the tracking is racy: operations on
static_branch are not serialized against adding/removing unaccepted pages
to/from the zone.
Sanity checks inside static_branch machinery detects it:
WARNING: CPU: 0 PID: 10 at kernel/jump_label.c:276 __static_key_slow_dec_cpuslocked+0x8e/0xa0
The comment around the WARN() explains the problem:
/*
* Warn about the '-1' case though; since that means a
* decrement is concurrent with a first (0->1) increment. IOW
* people are trying to disable something that wasn't yet fully
* enabled. This suggests an ordering problem on the user side.
*/
The effect of this static_branch optimization is only visible on
microbenchmark.
Instead of adding more complexity around it, remove it altogether.