In the Linux kernel, the following vulnerability has been resolved:
net: do not write to msg_get_inq in callee
NULL pointer dereference fix.
msg_get_inq is an input field from caller to callee. Don't set it in
the callee, as the caller may not clear it on struct reuse.
This is a kernel-internal variant of msghdr only, and the only user
does reinitialize the field. So this is not critical for that reason.
But it is more robust to avoid the write, and slightly simpler code.
And it fixes a bug, see below.
Callers set msg_get_inq to request the input queue length to be
returned in msg_inq. This is equivalent to but independent from the
SO_INQ request to return that same info as a cmsg (tp->recvmsg_inq).
To reduce branching in the hot path the second also sets the msg_inq.
That is WAI.
This is a fix to commit 4d1442979e4a ("af_unix: don't post cmsg for
SO_INQ unless explicitly asked for"), which fixed the inverse.
Also avoid NULL pointer dereference in unix_stream_read_generic if
state->msg is NULL and msg->msg_get_inq is written. A NULL state->msg
can happen when splicing as of commit 2b514574f7e8 ("net: af_unix:
implement splice for stream af_unix sockets").
Also collapse two branches using a bitwise or.
In the Linux kernel, the following vulnerability has been resolved:
libceph: prevent potential out-of-bounds reads in handle_auth_done()
Perform an explicit bounds check on payload_len to avoid a possible
out-of-bounds access in the callout.
[ idryomov: changelog ]
In the Linux kernel, the following vulnerability has been resolved:
idpf: Fix RSS LUT NULL pointer crash on early ethtool operations
The RSS LUT is not initialized until the interface comes up, causing
the following NULL pointer crash when ethtool operations like rxhash on/off
are performed before the interface is brought up for the first time.
Move RSS LUT initialization from ndo_open to vport creation to ensure LUT
is always available. This enables RSS configuration via ethtool before
bringing the interface up. Simplify LUT management by maintaining all
changes in the driver's soft copy and programming zeros to the indirection
table when rxhash is disabled. Defer HW programming until the interface
comes up if it is down during rxhash and LUT configuration changes.
Steps to reproduce:
** Load idpf driver; interfaces will be created
modprobe idpf
** Before bringing the interfaces up, turn rxhash off
ethtool -K eth2 rxhash off
[89408.371875] BUG: kernel NULL pointer dereference, address: 0000000000000000
[89408.371908] #PF: supervisor read access in kernel mode
[89408.371924] #PF: error_code(0x0000) - not-present page
[89408.371940] PGD 0 P4D 0
[89408.371953] Oops: Oops: 0000 [#1] SMP NOPTI
<snip>
[89408.372052] RIP: 0010:memcpy_orig+0x16/0x130
[89408.372310] Call Trace:
[89408.372317] <TASK>
[89408.372326] ? idpf_set_features+0xfc/0x180 [idpf]
[89408.372363] __netdev_update_features+0x295/0xde0
[89408.372384] ethnl_set_features+0x15e/0x460
[89408.372406] genl_family_rcv_msg_doit+0x11f/0x180
[89408.372429] genl_rcv_msg+0x1ad/0x2b0
[89408.372446] ? __pfx_ethnl_set_features+0x10/0x10
[89408.372465] ? __pfx_genl_rcv_msg+0x10/0x10
[89408.372482] netlink_rcv_skb+0x58/0x100
[89408.372502] genl_rcv+0x2c/0x50
[89408.372516] netlink_unicast+0x289/0x3e0
[89408.372533] netlink_sendmsg+0x215/0x440
[89408.372551] __sys_sendto+0x234/0x240
[89408.372571] __x64_sys_sendto+0x28/0x30
[89408.372585] x64_sys_call+0x1909/0x1da0
[89408.372604] do_syscall_64+0x7a/0xfa0
[89408.373140] ? clear_bhb_loop+0x60/0xb0
[89408.373647] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[89408.378887] </TASK>
<snip>
In the Linux kernel, the following vulnerability has been resolved:
gpiolib: fix race condition for gdev->srcu
If two drivers were calling gpiochip_add_data_with_key(), one may be
traversing the srcu-protected list in gpio_name_to_desc(), meanwhile
other has just added its gdev in gpiodev_add_to_list_unlocked().
This creates a non-mutexed and non-protected timeframe, when one
instance is dereferencing and using &gdev->srcu, before the other
has initialized it, resulting in crash:
[ 4.935481] Unable to handle kernel paging request at virtual address ffff800272bcc000
[ 4.943396] Mem abort info:
[ 4.943400] ESR = 0x0000000096000005
[ 4.943403] EC = 0x25: DABT (current EL), IL = 32 bits
[ 4.943407] SET = 0, FnV = 0
[ 4.943410] EA = 0, S1PTW = 0
[ 4.943413] FSC = 0x05: level 1 translation fault
[ 4.943416] Data abort info:
[ 4.943418] ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
[ 4.946220] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[ 4.955261] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[ 4.955268] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000038e6c000
[ 4.961449] [ffff800272bcc000] pgd=0000000000000000
[ 4.969203] , p4d=1000000039739003
[ 4.979730] , pud=0000000000000000
[ 4.980210] phandle (CPU): 0x0000005e, phandle (BE): 0x5e000000 for node "reset"
[ 4.991736] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
...
[ 5.121359] pc : __srcu_read_lock+0x44/0x98
[ 5.131091] lr : gpio_name_to_desc+0x60/0x1a0
[ 5.153671] sp : ffff8000833bb430
[ 5.298440]
[ 5.298443] Call trace:
[ 5.298445] __srcu_read_lock+0x44/0x98
[ 5.309484] gpio_name_to_desc+0x60/0x1a0
[ 5.320692] gpiochip_add_data_with_key+0x488/0xf00
5.946419] ---[ end trace 0000000000000000 ]---
Move initialization code for gdev fields before it is added to
gpio_devices, with adjacent initialization code.
Adjust goto statements to reflect modified order of operations
[Bartosz: fixed a build issue, removed stray newline]
In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy
syzbot reported a crash in tc_act_in_hw() during netns teardown where
tcf_idrinfo_destroy() passed an ERR_PTR(-EBUSY) value as a tc_action
pointer, leading to an invalid dereference.
Guard against ERR_PTR entries when iterating the action IDR so teardown
does not call tc_act_in_hw() on an error pointer.
In the Linux kernel, the following vulnerability has been resolved:
arp: do not assume dev_hard_header() does not change skb->head
arp_create() is the only dev_hard_header() caller
making assumption about skb->head being unchanged.
A recent commit broke this assumption.
Initialize @arp pointer after dev_hard_header() call.
In the Linux kernel, the following vulnerability has been resolved:
nfsd: check that server is running in unlock_filesystem
If we are trying to unlock the filesystem via an administrative
interface and nfsd isn't running, it crashes the server. This
happens currently because nfsd4_revoke_states() access state
structures (eg., conf_id_hashtbl) that has been freed as a part
of the server shutdown.
[ 59.465072] Call trace:
[ 59.465308] nfsd4_revoke_states+0x1b4/0x898 [nfsd] (P)
[ 59.465830] write_unlock_fs+0x258/0x440 [nfsd]
[ 59.466278] nfsctl_transaction_write+0xb0/0x120 [nfsd]
[ 59.466780] vfs_write+0x1f0/0x938
[ 59.467088] ksys_write+0xfc/0x1f8
[ 59.467395] __arm64_sys_write+0x74/0xb8
[ 59.467746] invoke_syscall.constprop.0+0xdc/0x1e8
[ 59.468177] do_el0_svc+0x154/0x1d8
[ 59.468489] el0_svc+0x40/0xe0
[ 59.468767] el0t_64_sync_handler+0xa0/0xe8
[ 59.469138] el0t_64_sync+0x1ac/0x1b0
Ensure this can't happen by taking the nfsd_mutex and checking that
the server is still up, and then holding the mutex across the call to
nfsd4_revoke_states().
In the Linux kernel, the following vulnerability has been resolved:
dm-verity: disable recursive forward error correction
There are two problems with the recursive correction:
1. It may cause denial-of-service. In fec_read_bufs, there is a loop that
has 253 iterations. For each iteration, we may call verity_hash_for_block
recursively. There is a limit of 4 nested recursions - that means that
there may be at most 253^4 (4 billion) iterations. Red Hat QE team
actually created an image that pushes dm-verity to this limit - and this
image just makes the udev-worker process get stuck in the 'D' state.
2. It doesn't work. In fec_read_bufs we store data into the variable
"fio->bufs", but fio bufs is shared between recursive invocations, if
"verity_hash_for_block" invoked correction recursively, it would
overwrite partially filled fio->bufs.
In the Linux kernel, the following vulnerability has been resolved:
wifi: avoid kernel-infoleak from struct iw_point
struct iw_point has a 32bit hole on 64bit arches.
struct iw_point {
void __user *pointer; /* Pointer to the data (in user space) */
__u16 length; /* number of fields or size in bytes */
__u16 flags; /* Optional params */
};
Make sure to zero the structure to avoid disclosing 32bits of kernel data
to user space.
In the Linux kernel, the following vulnerability has been resolved:
net: fix memory leak in skb_segment_list for GRO packets
When skb_segment_list() is called during packet forwarding, it handles
packets that were aggregated by the GRO engine.
Historically, the segmentation logic in skb_segment_list assumes that
individual segments are split from a parent SKB and may need to carry
their own socket memory accounting. Accordingly, the code transfers
truesize from the parent to the newly created segments.
Prior to commit ed4cccef64c1 ("gro: fix ownership transfer"), this
truesize subtraction in skb_segment_list() was valid because fragments
still carry a reference to the original socket.
However, commit ed4cccef64c1 ("gro: fix ownership transfer") changed
this behavior by ensuring that fraglist entries are explicitly
orphaned (skb->sk = NULL) to prevent illegal orphaning later in the
stack. This change meant that the entire socket memory charge remained
with the head SKB, but the corresponding accounting logic in
skb_segment_list() was never updated.
As a result, the current code unconditionally adds each fragment's
truesize to delta_truesize and subtracts it from the parent SKB. Since
the fragments are no longer charged to the socket, this subtraction
results in an effective under-count of memory when the head is freed.
This causes sk_wmem_alloc to remain non-zero, preventing socket
destruction and leading to a persistent memory leak.
The leak can be observed via KMEMLEAK when tearing down the networking
environment:
unreferenced object 0xffff8881e6eb9100 (size 2048):
comm "ping", pid 6720, jiffies 4295492526
backtrace:
kmem_cache_alloc_noprof+0x5c6/0x800
sk_prot_alloc+0x5b/0x220
sk_alloc+0x35/0xa00
inet6_create.part.0+0x303/0x10d0
__sock_create+0x248/0x640
__sys_socket+0x11b/0x1d0
Since skb_segment_list() is exclusively used for SKB_GSO_FRAGLIST
packets constructed by GRO, the truesize adjustment is removed.
The call to skb_release_head_state() must be preserved. As documented in
commit cf673ed0e057 ("net: fix fraglist segmentation reference count
leak"), it is still required to correctly drop references to SKB
extensions that may be overwritten during __copy_skb_header().