In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix bpf_sk_select_reuseport() memory leak
As pointed out in the original comment, lookup in sockmap can return a TCP
ESTABLISHED socket. Such TCP socket may have had SO_ATTACH_REUSEPORT_EBPF
set before it was ESTABLISHED. In other words, a non-NULL sk_reuseport_cb
does not imply a non-refcounted socket.
Drop sk's reference in both error paths.
unreferenced object 0xffff888101911800 (size 2048):
comm "test_progs", pid 44109, jiffies 4297131437
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
80 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 9336483b):
__kmalloc_noprof+0x3bf/0x560
__reuseport_alloc+0x1d/0x40
reuseport_alloc+0xca/0x150
reuseport_attach_prog+0x87/0x140
sk_reuseport_attach_bpf+0xc8/0x100
sk_setsockopt+0x1181/0x1990
do_sock_setsockopt+0x12b/0x160
__sys_setsockopt+0x7b/0xc0
__x64_sys_setsockopt+0x1b/0x30
do_syscall_64+0x93/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: discard packets if the transport changes
If the socket has been de-assigned or assigned to another transport,
we must discard any packets received because they are not expected
and would cause issues when we access vsk->transport.
A possible scenario is described by Hyunwoo Kim in the attached link,
where after a first connect() interrupted by a signal, and a second
connect() failed, we can find `vsk->transport` at NULL, leading to a
NULL pointer dereference.
In the Linux kernel, the following vulnerability has been resolved:
afs: Fix merge preference rule failure condition
syzbot reported a lock held when returning to userspace[1]. This is
because if argc is less than 0 and the function returns directly, the held
inode lock is not released.
Fix this by store the error in ret and jump to done to clean up instead of
returning directly.
[dh: Modified Lizhi Xu's original patch to make it honour the error code
from afs_split_string()]
[1]
WARNING: lock held when returning to user space!
6.13.0-rc3-syzkaller-00209-g499551201b5f #0 Not tainted
------------------------------------------------
syz-executor133/5823 is leaving the kernel with locks still held!
1 lock held by syz-executor133/5823:
#0: ffff888071cffc00 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
#0: ffff888071cffc00 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: afs_proc_addr_prefs_write+0x2bb/0x14e0 fs/afs/addr_prefs.c:388
In the Linux kernel, the following vulnerability has been resolved:
net: fec: handle page_pool_dev_alloc_pages error
The fec_enet_update_cbd function calls page_pool_dev_alloc_pages but did
not handle the case when it returned NULL. There was a WARN_ON(!new_page)
but it would still proceed to use the NULL pointer and then crash.
This case does seem somewhat rare but when the system is under memory
pressure it can happen. One case where I can duplicate this with some
frequency is when writing over a smbd share to a SATA HDD attached to an
imx6q.
Setting /proc/sys/vm/min_free_kbytes to higher values also seems to solve
the problem for my test case. But it still seems wrong that the fec driver
ignores the memory allocation error and can crash.
This commit handles the allocation error by dropping the current packet.
In the Linux kernel, the following vulnerability has been resolved:
filemap: avoid truncating 64-bit offset to 32 bits
On 32-bit kernels, folio_seek_hole_data() was inadvertently truncating a
64-bit value to 32 bits, leading to a possible infinite loop when writing
to an xfs filesystem.
In the Linux kernel, the following vulnerability has been resolved:
vsock: prevent null-ptr-deref in vsock_*[has_data|has_space]
Recent reports have shown how we sometimes call vsock_*_has_data()
when a vsock socket has been de-assigned from a transport (see attached
links), but we shouldn't.
Previous commits should have solved the real problems, but we may have
more in the future, so to avoid null-ptr-deref, we can return 0
(no space, no data available) but with a warning.
This way the code should continue to run in a nearly consistent state
and have a warning that allows us to debug future problems.