In the Linux kernel, the following vulnerability has been resolved:
RDMA/hfi1: Fix potential integer multiplication overflow errors
When multiplying of different types, an overflow is possible even when
storing the result in a larger type. This is because the conversion is
done after the multiplication. So arithmetic overflow and thus in
incorrect value is possible.
Correct an instance of this in the inter packet delay calculation. Fix by
ensuring one of the operands is u64 which will promote the other to u64 as
well ensuring no overflow.
In the Linux kernel, the following vulnerability has been resolved:
driver: base: fix UAF when driver_attach failed
When driver_attach(drv); failed, the driver_private will be freed.
But it has been added to the bus, which caused a UAF.
To fix it, we need to delete it from the bus when failed.
In the Linux kernel, the following vulnerability has been resolved:
usb: usbip: fix a refcount leak in stub_probe()
usb_get_dev() is called in stub_device_alloc(). When stub_probe() fails
after that, usb_put_dev() needs to be called to release the reference.
Fix this by moving usb_put_dev() to sdev_free error path handling.
Find this by code review.
In the Linux kernel, the following vulnerability has been resolved:
rtc: mt6397: check return value after calling platform_get_resource()
It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid f2fs_bug_on() in dec_valid_node_count()
As Yanming reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215897
I have encountered a bug in F2FS file system in kernel v5.17.
The kernel should enable CONFIG_KASAN=y and CONFIG_KASAN_INLINE=y. You can
reproduce the bug by running the following commands:
The kernel message is shown below:
kernel BUG at fs/f2fs/f2fs.h:2511!
Call Trace:
f2fs_remove_inode_page+0x2a2/0x830
f2fs_evict_inode+0x9b7/0x1510
evict+0x282/0x4e0
do_unlinkat+0x33a/0x540
__x64_sys_unlinkat+0x8e/0xd0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is: .total_valid_block_count or .total_valid_node_count
could fuzzed to zero, then once dec_valid_node_count() was called, it
will cause BUG_ON(), this patch fixes to print warning info and set
SBI_NEED_FSCK into CP instead of panic.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to clear dirty inode in f2fs_evict_inode()
As Yanming reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215904
The kernel message is shown below:
kernel BUG at fs/f2fs/inode.c:825!
Call Trace:
evict+0x282/0x4e0
__dentry_kill+0x2b2/0x4d0
shrink_dentry_list+0x17c/0x4f0
shrink_dcache_parent+0x143/0x1e0
do_one_tree+0x9/0x30
shrink_dcache_for_umount+0x51/0x120
generic_shutdown_super+0x5c/0x3a0
kill_block_super+0x90/0xd0
kill_f2fs_super+0x225/0x310
deactivate_locked_super+0x78/0xc0
cleanup_mnt+0x2b7/0x480
task_work_run+0xc8/0x150
exit_to_user_mode_prepare+0x14a/0x150
syscall_exit_to_user_mode+0x1d/0x40
do_syscall_64+0x48/0x90
The root cause is: inode node and dnode node share the same nid,
so during f2fs_evict_inode(), dnode node truncation will invalidate
its NAT entry, so when truncating inode node, it fails due to
invalid NAT entry, result in inode is still marked as dirty, fix
this issue by clearing dirty for inode and setting SBI_NEED_FSCK
flag in filesystem.
output from dump.f2fs:
[print_node_info: 354] Node ID [0xf:15] is inode
i_nid[0] [0x f : 15]
In the Linux kernel, the following vulnerability has been resolved:
firmware: dmi-sysfs: Fix memory leak in dmi_sysfs_register_handle
kobject_init_and_add() takes reference even when it fails.
According to the doc of kobject_init_and_add()
If this function returns an error, kobject_put() must be called to
properly clean up the memory associated with the object.
Fix this issue by calling kobject_put().
In the Linux kernel, the following vulnerability has been resolved:
driver core: fix deadlock in __device_attach
In __device_attach function, The lock holding logic is as follows:
...
__device_attach
device_lock(dev) // get lock dev
async_schedule_dev(__device_attach_async_helper, dev); // func
async_schedule_node
async_schedule_node_domain(func)
entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC);
/* when fail or work limit, sync to execute func, but
__device_attach_async_helper will get lock dev as
well, which will lead to A-A deadlock. */
if (!entry || atomic_read(&entry_count) > MAX_WORK) {
func;
else
queue_work_node(node, system_unbound_wq, &entry->work)
device_unlock(dev)
As shown above, when it is allowed to do async probes, because of
out of memory or work limit, async work is not allowed, to do
sync execute instead. it will lead to A-A deadlock because of
__device_attach_async_helper getting lock dev.
To fix the deadlock, move the async_schedule_dev outside device_lock,
as we can see, in async_schedule_node_domain, the parameter of
queue_work_node is system_unbound_wq, so it can accept concurrent
operations. which will also not change the code logic, and will
not lead to deadlock.
In the Linux kernel, the following vulnerability has been resolved:
tcp: tcp_rtx_synack() can be called from process context
Laurent reported the enclosed report [1]
This bug triggers with following coditions:
0) Kernel built with CONFIG_DEBUG_PREEMPT=y
1) A new passive FastOpen TCP socket is created.
This FO socket waits for an ACK coming from client to be a complete
ESTABLISHED one.
2) A socket operation on this socket goes through lock_sock()
release_sock() dance.
3) While the socket is owned by the user in step 2),
a retransmit of the SYN is received and stored in socket backlog.
4) At release_sock() time, the socket backlog is processed while
in process context.
5) A SYNACK packet is cooked in response of the SYN retransmit.
6) -> tcp_rtx_synack() is called in process context.
Before blamed commit, tcp_rtx_synack() was always called from BH handler,
from a timer handler.
Fix this by using TCP_INC_STATS() & NET_INC_STATS()
which do not assume caller is in non preemptible context.
[1]
BUG: using __this_cpu_add() in preemptible [00000000] code: epollpep/2180
caller is tcp_rtx_synack.part.0+0x36/0xc0
CPU: 10 PID: 2180 Comm: epollpep Tainted: G OE 5.16.0-0.bpo.4-amd64 #1 Debian 5.16.12-1~bpo11+1
Hardware name: Supermicro SYS-5039MC-H8TRF/X11SCD-F, BIOS 1.7 11/23/2021
Call Trace:
<TASK>
dump_stack_lvl+0x48/0x5e
check_preemption_disabled+0xde/0xe0
tcp_rtx_synack.part.0+0x36/0xc0
tcp_rtx_synack+0x8d/0xa0
? kmem_cache_alloc+0x2e0/0x3e0
? apparmor_file_alloc_security+0x3b/0x1f0
inet_rtx_syn_ack+0x16/0x30
tcp_check_req+0x367/0x610
tcp_rcv_state_process+0x91/0xf60
? get_nohz_timer_target+0x18/0x1a0
? lock_timer_base+0x61/0x80
? preempt_count_add+0x68/0xa0
tcp_v4_do_rcv+0xbd/0x270
__release_sock+0x6d/0xb0
release_sock+0x2b/0x90
sock_setsockopt+0x138/0x1140
? __sys_getsockname+0x7e/0xc0
? aa_sk_perm+0x3e/0x1a0
__sys_setsockopt+0x198/0x1e0
__x64_sys_setsockopt+0x21/0x30
do_syscall_64+0x38/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae