In the Linux kernel, the following vulnerability has been resolved:
tipc: do not update mtu if msg_max is too small in mtu negotiation
When doing link mtu negotiation, a malicious peer may send Activate msg
with a very small mtu, e.g. 4 in Shuang's testing, without checking for
the minimum mtu, l->mtu will be set to 4 in tipc_link_proto_rcv(), then
n->links[bearer_id].mtu is set to 4294967228, which is a overflow of
'4 - INT_H_SIZE - EMSG_OVERHEAD' in tipc_link_mss().
With tipc_link.mtu = 4, tipc_link_xmit() kept printing the warning:
tipc: Too large msg, purging xmit list 1 5 0 40 4!
tipc: Too large msg, purging xmit list 1 15 0 60 4!
And with tipc_link_entry.mtu 4294967228, a huge skb was allocated in
named_distribute(), and when purging it in tipc_link_xmit(), a crash
was even caused:
general protection fault, probably for non-canonical address 0x2100001011000dd: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 0 Comm: swapper/0 Kdump: loaded Not tainted 6.3.0.neta #19
RIP: 0010:kfree_skb_list_reason+0x7e/0x1f0
Call Trace:
<IRQ>
skb_release_data+0xf9/0x1d0
kfree_skb_reason+0x40/0x100
tipc_link_xmit+0x57a/0x740 [tipc]
tipc_node_xmit+0x16c/0x5c0 [tipc]
tipc_named_node_up+0x27f/0x2c0 [tipc]
tipc_node_write_unlock+0x149/0x170 [tipc]
tipc_rcv+0x608/0x740 [tipc]
tipc_udp_recv+0xdc/0x1f0 [tipc]
udp_queue_rcv_one_skb+0x33e/0x620
udp_unicast_rcv_skb.isra.72+0x75/0x90
__udp4_lib_rcv+0x56d/0xc20
ip_protocol_deliver_rcu+0x100/0x2d0
This patch fixes it by checking the new mtu against tipc_bearer_min_mtu(),
and not updating mtu if it is too small.
In the Linux kernel, the following vulnerability has been resolved:
gpu: host1x: Fix memory leak of device names
The device names allocated by dev_set_name() need be freed
before module unloading, but they can not be freed because
the kobject's refcount which was set in device_initialize()
has not be decreased to 0.
As comment of device_add() says, if it fails, use only
put_device() drop the refcount, then the name will be
freed in kobejct_cleanup().
device_del() and put_device() can be replaced with
device_unregister(), so call it to unregister the added
successfully devices, and just call put_device() to the
not added device.
Add a release() function to device to avoid null release()
function WARNING in device_release(), it's empty, because
the context devices are freed together in
host1x_memory_context_list_free().
In the Linux kernel, the following vulnerability has been resolved:
nbd: fix incomplete validation of ioctl arg
We tested and found an alarm caused by nbd_ioctl arg without verification.
The UBSAN warning calltrace like below:
UBSAN: Undefined behaviour in fs/buffer.c:1709:35
signed integer overflow:
-9223372036854775808 - 1 cannot be represented in type 'long long int'
CPU: 3 PID: 2523 Comm: syz-executor.0 Not tainted 4.19.90 #1
Hardware name: linux,dummy-virt (DT)
Call trace:
dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78
show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x170/0x1dc lib/dump_stack.c:118
ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161
handle_overflow+0x188/0x1dc lib/ubsan.c:192
__ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:206
__block_write_full_page+0x94c/0xa20 fs/buffer.c:1709
block_write_full_page+0x1f0/0x280 fs/buffer.c:2934
blkdev_writepage+0x34/0x40 fs/block_dev.c:607
__writepage+0x68/0xe8 mm/page-writeback.c:2305
write_cache_pages+0x44c/0xc70 mm/page-writeback.c:2240
generic_writepages+0xdc/0x148 mm/page-writeback.c:2329
blkdev_writepages+0x2c/0x38 fs/block_dev.c:2114
do_writepages+0xd4/0x250 mm/page-writeback.c:2344
The reason for triggering this warning is __block_write_full_page()
-> i_size_read(inode) - 1 overflow.
inode->i_size is assigned in __nbd_ioctl() -> nbd_set_size() -> bytesize.
We think it is necessary to limit the size of arg to prevent errors.
Moreover, __nbd_ioctl() -> nbd_add_socket(), arg will be cast to int.
Assuming the value of arg is 0x80000000000000001) (on a 64-bit machine),
it will become 1 after the coercion, which will return unexpected results.
Fix it by adding checks to prevent passing in too large numbers.
In the Linux kernel, the following vulnerability has been resolved:
io_uring: fix fget leak when fs don't support nowait buffered read
Heming reported a BUG when using io_uring doing link-cp on ocfs2. [1]
Do the following steps can reproduce this BUG:
mount -t ocfs2 /dev/vdc /mnt/ocfs2
cp testfile /mnt/ocfs2/
./link-cp /mnt/ocfs2/testfile /mnt/ocfs2/testfile.1
umount /mnt/ocfs2
Then umount will fail, and it outputs:
umount: /mnt/ocfs2: target is busy.
While tracing umount, it blames mnt_get_count() not return as expected.
Do a deep investigation for fget()/fput() on related code flow, I've
finally found that fget() leaks since ocfs2 doesn't support nowait
buffered read.
io_issue_sqe
|-io_assign_file // do fget() first
|-io_read
|-io_iter_do_read
|-ocfs2_file_read_iter // return -EOPNOTSUPP
|-kiocb_done
|-io_rw_done
|-__io_complete_rw_common // set REQ_F_REISSUE
|-io_resubmit_prep
|-io_req_prep_async // override req->file, leak happens
This was introduced by commit a196c78b5443 in v5.18. Fix it by don't
re-assign req->file if it has already been assigned.
[1] https://lore.kernel.org/ocfs2-devel/ab580a75-91c8-d68a-3455-40361be1bfa8@linux.alibaba.com/T/#t
In the Linux kernel, the following vulnerability has been resolved:
qed: allow sleep in qed_mcp_trace_dump()
By default, qed_mcp_cmd_and_union() delays 10us at a time in a loop
that can run 500K times, so calls to qed_mcp_nvm_rd_cmd()
may block the current thread for over 5s.
We observed thread scheduling delays over 700ms in production,
with stacktraces pointing to this code as the culprit.
qed_mcp_trace_dump() is called from ethtool, so sleeping is permitted.
It already can sleep in qed_mcp_halt(), which calls qed_mcp_cmd().
Add a "can sleep" parameter to qed_find_nvram_image() and
qed_nvram_read() so they can sleep during qed_mcp_trace_dump().
qed_mcp_trace_get_meta_info() and qed_mcp_trace_read_meta(),
called only by qed_mcp_trace_dump(), allow these functions to sleep.
I can't tell if the other caller (qed_grc_dump_mcp_hw_dump()) can sleep,
so keep b_can_sleep set to false when it calls these functions.
An example stacktrace from a custom warning we added to the kernel
showing a thread that has not scheduled despite long needing resched:
[ 2745.362925,17] ------------[ cut here ]------------
[ 2745.362941,17] WARNING: CPU: 23 PID: 5640 at arch/x86/kernel/irq.c:233 do_IRQ+0x15e/0x1a0()
[ 2745.362946,17] Thread not rescheduled for 744 ms after irq 99
[ 2745.362956,17] Modules linked in: ...
[ 2745.363339,17] CPU: 23 PID: 5640 Comm: lldpd Tainted: P O 4.4.182+ #202104120910+6d1da174272d.61x
[ 2745.363343,17] Hardware name: FOXCONN MercuryB/Quicksilver Controller, BIOS H11P1N09 07/08/2020
[ 2745.363346,17] 0000000000000000 ffff885ec07c3ed8 ffffffff8131eb2f ffff885ec07c3f20
[ 2745.363358,17] ffffffff81d14f64 ffff885ec07c3f10 ffffffff81072ac2 ffff88be98ed0000
[ 2745.363369,17] 0000000000000063 0000000000000174 0000000000000074 0000000000000000
[ 2745.363379,17] Call Trace:
[ 2745.363382,17] <IRQ> [<ffffffff8131eb2f>] dump_stack+0x8e/0xcf
[ 2745.363393,17] [<ffffffff81072ac2>] warn_slowpath_common+0x82/0xc0
[ 2745.363398,17] [<ffffffff81072b4c>] warn_slowpath_fmt+0x4c/0x50
[ 2745.363404,17] [<ffffffff810d5a8e>] ? rcu_irq_exit+0xae/0xc0
[ 2745.363408,17] [<ffffffff817c99fe>] do_IRQ+0x15e/0x1a0
[ 2745.363413,17] [<ffffffff817c7ac9>] common_interrupt+0x89/0x89
[ 2745.363416,17] <EOI> [<ffffffff8132aa74>] ? delay_tsc+0x24/0x50
[ 2745.363425,17] [<ffffffff8132aa04>] __udelay+0x34/0x40
[ 2745.363457,17] [<ffffffffa04d45ff>] qed_mcp_cmd_and_union+0x36f/0x7d0 [qed]
[ 2745.363473,17] [<ffffffffa04d5ced>] qed_mcp_nvm_rd_cmd+0x4d/0x90 [qed]
[ 2745.363490,17] [<ffffffffa04e1dc7>] qed_mcp_trace_dump+0x4a7/0x630 [qed]
[ 2745.363504,17] [<ffffffffa04e2556>] ? qed_fw_asserts_dump+0x1d6/0x1f0 [qed]
[ 2745.363520,17] [<ffffffffa04e4ea7>] qed_dbg_mcp_trace_get_dump_buf_size+0x37/0x80 [qed]
[ 2745.363536,17] [<ffffffffa04ea881>] qed_dbg_feature_size+0x61/0xa0 [qed]
[ 2745.363551,17] [<ffffffffa04eb427>] qed_dbg_all_data_size+0x247/0x260 [qed]
[ 2745.363560,17] [<ffffffffa0482c10>] qede_get_regs_len+0x30/0x40 [qede]
[ 2745.363566,17] [<ffffffff816c9783>] ethtool_get_drvinfo+0xe3/0x190
[ 2745.363570,17] [<ffffffff816cc152>] dev_ethtool+0x1362/0x2140
[ 2745.363575,17] [<ffffffff8109bcc6>] ? finish_task_switch+0x76/0x260
[ 2745.363580,17] [<ffffffff817c2116>] ? __schedule+0x3c6/0x9d0
[ 2745.363585,17] [<ffffffff810dbd50>] ? hrtimer_start_range_ns+0x1d0/0x370
[ 2745.363589,17] [<ffffffff816c1e5b>] ? dev_get_by_name_rcu+0x6b/0x90
[ 2745.363594,17] [<ffffffff816de6a8>] dev_ioctl+0xe8/0x710
[ 2745.363599,17] [<ffffffff816a58a8>] sock_do_ioctl+0x48/0x60
[ 2745.363603,17] [<ffffffff816a5d87>] sock_ioctl+0x1c7/0x280
[ 2745.363608,17] [<ffffffff8111f393>] ? seccomp_phase1+0x83/0x220
[ 2745.363612,17] [<ffffffff811e3503>] do_vfs_ioctl+0x2b3/0x4e0
[ 2745.363616,17] [<ffffffff811e3771>] SyS_ioctl+0x41/0x70
[ 2745.363619,17] [<ffffffff817c6ffe>] entry_SYSCALL_64_fastpath+0x1e/0x79
[ 2745.363622,17] ---[ end trace f6954aa440266421 ]---
In the Linux kernel, the following vulnerability has been resolved:
clk: tegra: tegra124-emc: Fix potential memory leak
The tegra and tegra needs to be freed in the error handling path, otherwise
it will be leaked.
In the Linux kernel, the following vulnerability has been resolved:
ext4: allow ext4_get_group_info() to fail
Previously, ext4_get_group_info() would treat an invalid group number
as BUG(), since in theory it should never happen. However, if a
malicious attaker (or fuzzer) modifies the superblock via the block
device while it is the file system is mounted, it is possible for
s_first_data_block to get set to a very large number. In that case,
when calculating the block group of some block number (such as the
starting block of a preallocation region), could result in an
underflow and very large block group number. Then the BUG_ON check in
ext4_get_group_info() would fire, resutling in a denial of service
attack that can be triggered by root or someone with write access to
the block device.
For a quality of implementation perspective, it's best that even if
the system administrator does something that they shouldn't, that it
will not trigger a BUG. So instead of BUG'ing, ext4_get_group_info()
will call ext4_error and return NULL. We also add fallback code in
all of the callers of ext4_get_group_info() that it might NULL.
Also, since ext4_get_group_info() was already borderline to be an
inline function, un-inline it. The results in a next reduction of the
compiled text size of ext4 by roughly 2k.
In the Linux kernel, the following vulnerability has been resolved:
iommu/amd/iommu_v2: Fix pasid_state refcount dec hit 0 warning on pasid unbind
When unbinding pasid - a race condition exists vs outstanding page faults.
To prevent this, the pasid_state object contains a refcount.
* set to 1 on pasid bind
* incremented on each ppr notification start
* decremented on each ppr notification done
* decremented on pasid unbind
Since refcount_dec assumes that refcount will never reach 0:
the current implementation causes the following to be invoked on
pasid unbind:
REFCOUNT_WARN("decrement hit 0; leaking memory")
Fix this issue by changing refcount_dec to refcount_dec_and_test
to explicitly handle refcount=1.
In the Linux kernel, the following vulnerability has been resolved:
virtio_net: Fix error unwinding of XDP initialization
When initializing XDP in virtnet_open(), some rq xdp initialization
may hit an error causing net device open failed. However, previous
rqs have already initialized XDP and enabled NAPI, which is not the
expected behavior. Need to roll back the previous rq initialization
to avoid leaks in error unwinding of init code.
Also extract helper functions of disable and enable queue pairs.
Use newly introduced disable helper function in error unwinding and
virtnet_close. Use enable helper function in virtnet_open.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix potential null dereference
The adev->dm.dc pointer can be NULL and dereferenced in amdgpu_dm_fini()
without checking.
Add a NULL pointer check before calling dc_dmub_srv_destroy().
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
x86/platform/uv: Use alternate source for socket to node data
The UV code attempts to build a set of tables to allow it to do
bidirectional socket<=>node lookups.
But when nr_cpus is set to a smaller number than actually present, the
cpu_to_node() mapping information for unused CPUs is not available to
build_socket_tables(). This results in skipping some nodes or sockets
when creating the tables and leaving some -1's for later code to trip.
over, causing oopses.
The problem is that the socket<=>node lookups are created by doing a
loop over all CPUs, then looking up the CPU's APICID and socket. But
if a CPU is not present, there is no way to start this lookup.
Instead of looping over all CPUs, take CPUs out of the equation
entirely. Loop over all APICIDs which are mapped to a valid NUMA node.
Then just extract the socket-id from the APICID.
This avoid tripping over disabled CPUs.
In the Linux kernel, the following vulnerability has been resolved:
start_kernel: Add __no_stack_protector function attribute
Back during the discussion of
commit a9a3ed1eff36 ("x86: Fix early boot crash on gcc-10, third try")
we discussed the need for a function attribute to control the omission
of stack protectors on a per-function basis; at the time Clang had
support for no_stack_protector but GCC did not. This was fixed in
gcc-11. Now that the function attribute is available, let's start using
it.
Callers of boot_init_stack_canary need to use this function attribute
unless they're compiled with -fno-stack-protector, otherwise the canary
stored in the stack slot of the caller will differ upon the call to
boot_init_stack_canary. This will lead to a call to __stack_chk_fail()
then panic.
In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix disconnect vs accept race
Despite commit 0ad529d9fd2b ("mptcp: fix possible divide by zero in
recvmsg()"), the mptcp protocol is still prone to a race between
disconnect() (or shutdown) and accept.
The root cause is that the mentioned commit checks the msk-level
flag, but mptcp_stream_accept() does acquire the msk-level lock,
as it can rely directly on the first subflow lock.
As reported by Christoph than can lead to a race where an msk
socket is accepted after that mptcp_subflow_queue_clean() releases
the listener socket lock and just before it takes destructive
actions leading to the following splat:
BUG: kernel NULL pointer dereference, address: 0000000000000012
PGD 5a4ca067 P4D 5a4ca067 PUD 37d4c067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 2 PID: 10955 Comm: syz-executor.5 Not tainted 6.5.0-rc1-gdc7b257ee5dd #37
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
RIP: 0010:mptcp_stream_accept+0x1ee/0x2f0 include/net/inet_sock.h:330
Code: 0a 09 00 48 8b 1b 4c 39 e3 74 07 e8 bc 7c 7f fe eb a1 e8 b5 7c 7f fe 4c 8b 6c 24 08 eb 05 e8 a9 7c 7f fe 49 8b 85 d8 09 00 00 <0f> b6 40 12 88 44 24 07 0f b6 6c 24 07 bf 07 00 00 00 89 ee e8 89
RSP: 0018:ffffc90000d07dc0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888037e8d020 RCX: ffff88803b093300
RDX: 0000000000000000 RSI: ffffffff833822c5 RDI: ffffffff8333896a
RBP: 0000607f82031520 R08: ffff88803b093300 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000003e83 R12: ffff888037e8d020
R13: ffff888037e8c680 R14: ffff888009af7900 R15: ffff888009af6880
FS: 00007fc26d708640(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000012 CR3: 0000000066bc5001 CR4: 0000000000370ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
do_accept+0x1ae/0x260 net/socket.c:1872
__sys_accept4+0x9b/0x110 net/socket.c:1913
__do_sys_accept4 net/socket.c:1954 [inline]
__se_sys_accept4 net/socket.c:1951 [inline]
__x64_sys_accept4+0x20/0x30 net/socket.c:1951
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x47/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Address the issue by temporary removing the pending request socket
from the accept queue, so that racing accept() can't touch them.
After depleting the msk - the ssk still exists, as plain TCP sockets,
re-insert them into the accept queue, so that later inet_csk_listen_stop()
will complete the tcp socket disposal.
In the Linux kernel, the following vulnerability has been resolved:
tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.
syzkaller reported [0] memory leaks of an UDP socket and ZEROCOPY
skbs. We can reproduce the problem with these sequences:
sk = socket(AF_INET, SOCK_DGRAM, 0)
sk.setsockopt(SOL_SOCKET, SO_TIMESTAMPING, SOF_TIMESTAMPING_TX_SOFTWARE)
sk.setsockopt(SOL_SOCKET, SO_ZEROCOPY, 1)
sk.sendto(b'', MSG_ZEROCOPY, ('127.0.0.1', 53))
sk.close()
sendmsg() calls msg_zerocopy_alloc(), which allocates a skb, sets
skb->cb->ubuf.refcnt to 1, and calls sock_hold(). Here, struct
ubuf_info_msgzc indirectly holds a refcnt of the socket. When the
skb is sent, __skb_tstamp_tx() clones it and puts the clone into
the socket's error queue with the TX timestamp.
When the original skb is received locally, skb_copy_ubufs() calls
skb_unclone(), and pskb_expand_head() increments skb->cb->ubuf.refcnt.
This additional count is decremented while freeing the skb, but struct
ubuf_info_msgzc still has a refcnt, so __msg_zerocopy_callback() is
not called.
The last refcnt is not released unless we retrieve the TX timestamped
skb by recvmsg(). Since we clear the error queue in inet_sock_destruct()
after the socket's refcnt reaches 0, there is a circular dependency.
If we close() the socket holding such skbs, we never call sock_put()
and leak the count, sk, and skb.
TCP has the same problem, and commit e0c8bccd40fc ("net: stream:
purge sk_error_queue in sk_stream_kill_queues()") tried to fix it
by calling skb_queue_purge() during close(). However, there is a
small chance that skb queued in a qdisc or device could be put
into the error queue after the skb_queue_purge() call.
In __skb_tstamp_tx(), the cloned skb should not have a reference
to the ubuf to remove the circular dependency, but skb_clone() does
not call skb_copy_ubufs() for zerocopy skb. So, we need to call
skb_orphan_frags_rx() for the cloned skb to call skb_copy_ubufs().
[0]:
BUG: memory leak
unreferenced object 0xffff88800c6d2d00 (size 1152):
comm "syz-executor392", pid 264, jiffies 4294785440 (age 13.044s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 cd af e8 81 00 00 00 00 ................
02 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00 ...@............
backtrace:
[<0000000055636812>] sk_prot_alloc+0x64/0x2a0 net/core/sock.c:2024
[<0000000054d77b7a>] sk_alloc+0x3b/0x800 net/core/sock.c:2083
[<0000000066f3c7e0>] inet_create net/ipv4/af_inet.c:319 [inline]
[<0000000066f3c7e0>] inet_create+0x31e/0xe40 net/ipv4/af_inet.c:245
[<000000009b83af97>] __sock_create+0x2ab/0x550 net/socket.c:1515
[<00000000b9b11231>] sock_create net/socket.c:1566 [inline]
[<00000000b9b11231>] __sys_socket_create net/socket.c:1603 [inline]
[<00000000b9b11231>] __sys_socket_create net/socket.c:1588 [inline]
[<00000000b9b11231>] __sys_socket+0x138/0x250 net/socket.c:1636
[<000000004fb45142>] __do_sys_socket net/socket.c:1649 [inline]
[<000000004fb45142>] __se_sys_socket net/socket.c:1647 [inline]
[<000000004fb45142>] __x64_sys_socket+0x73/0xb0 net/socket.c:1647
[<0000000066999e0e>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<0000000066999e0e>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80
[<0000000017f238c1>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
BUG: memory leak
unreferenced object 0xffff888017633a00 (size 240):
comm "syz-executor392", pid 264, jiffies 4294785440 (age 13.044s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 2d 6d 0c 80 88 ff ff .........-m.....
backtrace:
[<000000002b1c4368>] __alloc_skb+0x229/0x320 net/core/skbuff.c:497
[<00000000143579a6>] alloc_skb include/linux/skbuff.h:1265 [inline]
[<00000000143579a6>] sock_omalloc+0xaa/0x190 net/core/sock.c:2596
[<00000000be626478>] msg_zerocopy_alloc net/core/skbuff.c:1294 [inline]
[<00000000be626478>]
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
IB/hfi1: Fix possible panic during hotplug remove
During hotplug remove it is possible that the update counters work
might be pending, and may run after memory has been freed.
Cancel the update counters work before freeing memory.
In the Linux kernel, the following vulnerability has been resolved:
ACPI: processor: Check for null return of devm_kzalloc() in fch_misc_setup()
devm_kzalloc() may fail, clk_data->name might be NULL and will
cause a NULL pointer dereference later.
[ rjw: Subject and changelog edits ]
In the Linux kernel, the following vulnerability has been resolved:
iommu: Fix error unwind in iommu_group_alloc()
If either iommu_group_grate_file() fails then the
iommu_group is leaked.
Destroy it on these error paths.
Found by kselftest/iommu/iommufd_fail_nth
In the Linux kernel, the following vulnerability has been resolved:
ubi: ubi_wl_put_peb: Fix infinite loop when wear-leveling work failed
Following process will trigger an infinite loop in ubi_wl_put_peb():
ubifs_bgt ubi_bgt
ubifs_leb_unmap
ubi_leb_unmap
ubi_eba_unmap_leb
ubi_wl_put_peb wear_leveling_worker
e1 = rb_entry(rb_first(&ubi->used)
e2 = get_peb_for_wl(ubi)
ubi_io_read_vid_hdr // return err (flash fault)
out_error:
ubi->move_from = ubi->move_to = NULL
wl_entry_destroy(ubi, e1)
ubi->lookuptbl[e->pnum] = NULL
retry:
e = ubi->lookuptbl[pnum]; // return NULL
if (e == ubi->move_from) { // NULL == NULL gets true
goto retry; // infinite loop !!!
$ top
PID USER PR NI VIRT RES SHR S %CPU %MEM COMMAND
7676 root 20 0 0 0 0 R 100.0 0.0 ubifs_bgt0_0
Fix it by:
1) Letting ubi_wl_put_peb() returns directly if wearl leveling entry has
been removed from 'ubi->lookuptbl'.
2) Using 'ubi->wl_lock' protecting wl entry deletion to preventing an
use-after-free problem for wl entry in ubi_wl_put_peb().
Fetch a reproducer in [Link].
In the Linux kernel, the following vulnerability has been resolved:
kobject: Add sanity check for kset->kobj.ktype in kset_register()
When I register a kset in the following way:
static struct kset my_kset;
kobject_set_name(&my_kset.kobj, "my_kset");
ret = kset_register(&my_kset);
A null pointer dereference exception is occurred:
[ 4453.568337] Unable to handle kernel NULL pointer dereference at \
virtual address 0000000000000028
... ...
[ 4453.810361] Call trace:
[ 4453.813062] kobject_get_ownership+0xc/0x34
[ 4453.817493] kobject_add_internal+0x98/0x274
[ 4453.822005] kset_register+0x5c/0xb4
[ 4453.825820] my_kobj_init+0x44/0x1000 [my_kset]
... ...
Because I didn't initialize my_kset.kobj.ktype.
According to the description in Documentation/core-api/kobject.rst:
- A ktype is the type of object that embeds a kobject. Every structure
that embeds a kobject needs a corresponding ktype.
So add sanity check to make sure kset->kobj.ktype is not NULL.
In the Linux kernel, the following vulnerability has been resolved:
tracing/synthetic: Fix races on freeing last_cmd
Currently, the "last_cmd" variable can be accessed by multiple processes
asynchronously when multiple users manipulate synthetic_events node
at the same time, it could lead to use-after-free or double-free.
This patch add "lastcmd_mutex" to prevent "last_cmd" from being accessed
asynchronously.
================================================================
It's easy to reproduce in the KASAN environment by running the two
scripts below in different shells.
script 1:
while :
do
echo -n -e '\x88' > /sys/kernel/tracing/synthetic_events
done
script 2:
while :
do
echo -n -e '\xb0' > /sys/kernel/tracing/synthetic_events
done
================================================================
double-free scenario:
process A process B
------------------- ---------------
1.kstrdup last_cmd
2.free last_cmd
3.free last_cmd(double-free)
================================================================
use-after-free scenario:
process A process B
------------------- ---------------
1.kstrdup last_cmd
2.free last_cmd
3.tracing_log_err(use-after-free)
================================================================
Appendix 1. KASAN report double-free:
BUG: KASAN: double-free in kfree+0xdc/0x1d4
Free of addr ***** by task sh/4879
Call trace:
...
kfree+0xdc/0x1d4
create_or_delete_synth_event+0x60/0x1e8
trace_parse_run_command+0x2bc/0x4b8
synth_events_write+0x20/0x30
vfs_write+0x200/0x830
...
Allocated by task 4879:
...
kstrdup+0x5c/0x98
create_or_delete_synth_event+0x6c/0x1e8
trace_parse_run_command+0x2bc/0x4b8
synth_events_write+0x20/0x30
vfs_write+0x200/0x830
...
Freed by task 5464:
...
kfree+0xdc/0x1d4
create_or_delete_synth_event+0x60/0x1e8
trace_parse_run_command+0x2bc/0x4b8
synth_events_write+0x20/0x30
vfs_write+0x200/0x830
...
================================================================
Appendix 2. KASAN report use-after-free:
BUG: KASAN: use-after-free in strlen+0x5c/0x7c
Read of size 1 at addr ***** by task sh/5483
sh: CPU: 7 PID: 5483 Comm: sh
...
__asan_report_load1_noabort+0x34/0x44
strlen+0x5c/0x7c
tracing_log_err+0x60/0x444
create_or_delete_synth_event+0xc4/0x204
trace_parse_run_command+0x2bc/0x4b8
synth_events_write+0x20/0x30
vfs_write+0x200/0x830
...
Allocated by task 5483:
...
kstrdup+0x5c/0x98
create_or_delete_synth_event+0x80/0x204
trace_parse_run_command+0x2bc/0x4b8
synth_events_write+0x20/0x30
vfs_write+0x200/0x830
...
Freed by task 5480:
...
kfree+0xdc/0x1d4
create_or_delete_synth_event+0x74/0x204
trace_parse_run_command+0x2bc/0x4b8
synth_events_write+0x20/0x30
vfs_write+0x200/0x830
...
In the Linux kernel, the following vulnerability has been resolved:
ipv6: Add lwtunnel encap size of all siblings in nexthop calculation
In function rt6_nlmsg_size(), the length of nexthop is calculated
by multipling the nexthop length of fib6_info and the number of
siblings. However if the fib6_info has no lwtunnel but the siblings
have lwtunnels, the nexthop length is less than it should be, and
it will trigger a warning in inet6_rt_notify() as follows:
WARNING: CPU: 0 PID: 6082 at net/ipv6/route.c:6180 inet6_rt_notify+0x120/0x130
......
Call Trace:
<TASK>
fib6_add_rt2node+0x685/0xa30
fib6_add+0x96/0x1b0
ip6_route_add+0x50/0xd0
inet6_rtm_newroute+0x97/0xa0
rtnetlink_rcv_msg+0x156/0x3d0
netlink_rcv_skb+0x5a/0x110
netlink_unicast+0x246/0x350
netlink_sendmsg+0x250/0x4c0
sock_sendmsg+0x66/0x70
___sys_sendmsg+0x7c/0xd0
__sys_sendmsg+0x5d/0xb0
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
This bug can be reproduced by script:
ip -6 addr add 2002::2/64 dev ens2
ip -6 route add 100::/64 via 2002::1 dev ens2 metric 100
for i in 10 20 30 40 50 60 70;
do
ip link add link ens2 name ipv_$i type ipvlan
ip -6 addr add 2002::$i/64 dev ipv_$i
ifconfig ipv_$i up
done
for i in 10 20 30 40 50 60;
do
ip -6 route append 100::/64 encap ip6 dst 2002::$i via 2002::1
dev ipv_$i metric 100
done
ip -6 route append 100::/64 via 2002::1 dev ipv_70 metric 100
This patch fixes it by adding nexthop_len of every siblings using
rt6_nh_nlmsg_size().
In the Linux kernel, the following vulnerability has been resolved:
iw_cxgb4: Fix potential NULL dereference in c4iw_fill_res_cm_id_entry()
This condition needs to match the previous "if (epcp->state == LISTEN) {"
exactly to avoid a NULL dereference of either "listen_ep" or "ep". The
problem is that "epcp" has been re-assigned so just testing
"if (epcp->state == LISTEN) {" a second time is not sufficient.
In the Linux kernel, the following vulnerability has been resolved:
usb: xhci: tegra: fix sleep in atomic call
When we set the dual-role port to Host mode, we observed the following
splat:
[ 167.057718] BUG: sleeping function called from invalid context at
include/linux/sched/mm.h:229
[ 167.057872] Workqueue: events tegra_xusb_usb_phy_work
[ 167.057954] Call trace:
[ 167.057962] dump_backtrace+0x0/0x210
[ 167.057996] show_stack+0x30/0x50
[ 167.058020] dump_stack_lvl+0x64/0x84
[ 167.058065] dump_stack+0x14/0x34
[ 167.058100] __might_resched+0x144/0x180
[ 167.058140] __might_sleep+0x64/0xd0
[ 167.058171] slab_pre_alloc_hook.constprop.0+0xa8/0x110
[ 167.058202] __kmalloc_track_caller+0x74/0x2b0
[ 167.058233] kvasprintf+0xa4/0x190
[ 167.058261] kasprintf+0x58/0x90
[ 167.058285] tegra_xusb_find_port_node.isra.0+0x58/0xd0
[ 167.058334] tegra_xusb_find_port+0x38/0xa0
[ 167.058380] tegra_xusb_padctl_get_usb3_companion+0x38/0xd0
[ 167.058430] tegra_xhci_id_notify+0x8c/0x1e0
[ 167.058473] notifier_call_chain+0x88/0x100
[ 167.058506] atomic_notifier_call_chain+0x44/0x70
[ 167.058537] tegra_xusb_usb_phy_work+0x60/0xd0
[ 167.058581] process_one_work+0x1dc/0x4c0
[ 167.058618] worker_thread+0x54/0x410
[ 167.058650] kthread+0x188/0x1b0
[ 167.058672] ret_from_fork+0x10/0x20
The function tegra_xusb_padctl_get_usb3_companion eventually calls
tegra_xusb_find_port and this in turn calls kasprintf which might sleep
and so cannot be called from an atomic context.
Fix this by moving the call to tegra_xusb_padctl_get_usb3_companion to
the tegra_xhci_id_work function where it is really needed.
In the Linux kernel, the following vulnerability has been resolved:
x86/MCE/AMD: Use an u64 for bank_map
Thee maximum number of MCA banks is 64 (MAX_NR_BANKS), see
a0bc32b3cacf ("x86/mce: Increase maximum number of banks to 64").
However, the bank_map which contains a bitfield of which banks to
initialize is of type unsigned int and that overflows when those bit
numbers are >= 32, leading to UBSAN complaining correctly:
UBSAN: shift-out-of-bounds in arch/x86/kernel/cpu/mce/amd.c:1365:38
shift exponent 32 is too large for 32-bit type 'int'
Change the bank_map to a u64 and use the proper BIT_ULL() macro when
modifying bits in there.
[ bp: Rewrite commit message. ]
In the Linux kernel, the following vulnerability has been resolved:
pwm: lpc32xx: Remove handling of PWM channels
Because LPC32xx PWM controllers have only a single output which is
registered as the only PWM device/channel per controller, it is known in
advance that pwm->hwpwm value is always 0. On basis of this fact
simplify the code by removing operations with pwm->hwpwm, there is no
controls which require channel number as input.
Even though I wasn't aware at the time when I forward ported that patch,
this fixes a null pointer dereference as lpc32xx->chip.pwms is NULL
before devm_pwmchip_add() is called.
In the Linux kernel, the following vulnerability has been resolved:
ionic: catch failure from devlink_alloc
Add a check for NULL on the alloc return. If devlink_alloc() fails and
we try to use devlink_priv() on the NULL return, the kernel gets very
unhappy and panics. With this fix, the driver load will still fail,
but at least it won't panic the kernel.
In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw89: fix potential leak in rtw89_append_probe_req_ie()
Do `kfree_skb(new)` before `goto out` to prevent potential leak.
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7915: fix memory leak in mt7915_mcu_exit
Always purge mcu skb queues in mt7915_mcu_exit routine even if
mt7915_firmware_state fails.
In the Linux kernel, the following vulnerability has been resolved:
scsi: iscsi_tcp: Check that sock is valid before iscsi_set_param()
The validity of sock should be checked before assignment to avoid incorrect
values. Commit 57569c37f0ad ("scsi: iscsi: iscsi_tcp: Fix null-ptr-deref
while calling getpeername()") introduced this change which may lead to
inconsistent values of tcp_sw_conn->sendpage and conn->datadgst_en.
Fix the issue by moving the position of the assignment.
In the Linux kernel, the following vulnerability has been resolved:
ibmvnic: Do not reset dql stats on NON_FATAL err
All ibmvnic resets, make a call to netdev_tx_reset_queue() when
re-opening the device. netdev_tx_reset_queue() resets the num_queued
and num_completed byte counters. These stats are used in Byte Queue
Limit (BQL) algorithms. The difference between these two stats tracks
the number of bytes currently sitting on the physical NIC. ibmvnic
increases the number of queued bytes though calls to
netdev_tx_sent_queue() in the drivers xmit function. When, VIOS reports
that it is done transmitting bytes, the ibmvnic device increases the
number of completed bytes through calls to netdev_tx_completed_queue().
It is important to note that the driver batches its transmit calls and
num_queued is increased every time that an skb is added to the next
batch, not necessarily when the batch is sent to VIOS for transmission.
Unlike other reset types, a NON FATAL reset will not flush the sub crq
tx buffers. Therefore, it is possible for the batched skb array to be
partially full. So if there is call to netdev_tx_reset_queue() when
re-opening the device, the value of num_queued (0) would not account
for the skb's that are currently batched. Eventually, when the batch
is sent to VIOS, the call to netdev_tx_completed_queue() would increase
num_completed to a value greater than the num_queued. This causes a
BUG_ON crash:
ibmvnic 30000002: Firmware reports error, cause: adapter problem.
Starting recovery...
ibmvnic 30000002: tx error 600
ibmvnic 30000002: tx error 600
ibmvnic 30000002: tx error 600
ibmvnic 30000002: tx error 600
------------[ cut here ]------------
kernel BUG at lib/dynamic_queue_limits.c:27!
Oops: Exception in kernel mode, sig: 5
[....]
NIP dql_completed+0x28/0x1c0
LR ibmvnic_complete_tx.isra.0+0x23c/0x420 [ibmvnic]
Call Trace:
ibmvnic_complete_tx.isra.0+0x3f8/0x420 [ibmvnic] (unreliable)
ibmvnic_interrupt_tx+0x40/0x70 [ibmvnic]
__handle_irq_event_percpu+0x98/0x270
---[ end trace ]---
Therefore, do not reset the dql stats when performing a NON_FATAL reset.
In the Linux kernel, the following vulnerability has been resolved:
io_uring: wait interruptibly for request completions on exit
WHen the ring exits, cleanup is done and the final cancelation and
waiting on completions is done by io_ring_exit_work. That function is
invoked by kworker, which doesn't take any signals. Because of that, it
doesn't really matter if we wait for completions in TASK_INTERRUPTIBLE
or TASK_UNINTERRUPTIBLE state. However, it does matter to the hung task
detection checker!
Normally we expect cancelations and completions to happen rather
quickly. Some test cases, however, will exit the ring and park the
owning task stopped (eg via SIGSTOP). If the owning task needs to run
task_work to complete requests, then io_ring_exit_work won't make any
progress until the task is runnable again. Hence io_ring_exit_work can
trigger the hung task detection, which is particularly problematic if
panic-on-hung-task is enabled.
As the ring exit doesn't take signals to begin with, have it wait
interruptibly rather than uninterruptibly. io_uring has a separate
stuck-exit warning that triggers independently anyway, so we're not
really missing anything by making this switch.
In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: fix memory leak in rtw_usb_probe()
drivers/net/wireless/realtek/rtw88/usb.c:876 rtw_usb_probe()
warn: 'hw' from ieee80211_alloc_hw() not released on lines: 811
Fix this by modifying return to a goto statement.
In the Linux kernel, the following vulnerability has been resolved:
media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer_finish()
When the driver calls cx23885_risc_buffer() to prepare the buffer, the
function call dma_alloc_coherent may fail, resulting in a empty buffer
risc->cpu. Later when we free the buffer or access the buffer, null ptr
deref is triggered.
This bug is similar to the following one:
https://git.linuxtv.org/media_stage.git/commit/?id=2b064d91440b33fba5b452f2d1b31f13ae911d71.
We believe the bug can be also dynamically triggered from user side.
Similarly, we fix this by checking the return value of cx23885_risc_buffer()
and the value of risc->cpu before buffer free.
In the Linux kernel, the following vulnerability has been resolved:
FS: JFS: Fix null-ptr-deref Read in txBegin
Syzkaller reported an issue where txBegin may be called
on a superblock in a read-only mounted filesystem which leads
to NULL pointer deref. This could be solved by checking if
the filesystem is read-only before calling txBegin, and returning
with appropiate error code.
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla4xxx: Add length check when parsing nlattrs
There are three places that qla4xxx parses nlattrs:
- qla4xxx_set_chap_entry()
- qla4xxx_iface_set_param()
- qla4xxx_sysfs_ddb_set_param()
and each of them directly converts the nlattr to specific pointer of
structure without length checking. This could be dangerous as those
attributes are not validated and a malformed nlattr (e.g., length 0) could
result in an OOB read that leaks heap dirty data.
Add the nla_len check before accessing the nlattr data and return EINVAL if
the length check fails.
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix potential NULL pointer dereference
Klocwork tool reported 'cur_dsd' may be dereferenced. Add fix to validate
pointer before dereferencing the pointer.
In the Linux kernel, the following vulnerability has been resolved:
ext4: remove a BUG_ON in ext4_mb_release_group_pa()
If a malicious fuzzer overwrites the ext4 superblock while it is
mounted such that the s_first_data_block is set to a very large
number, the calculation of the block group can underflow, and trigger
a BUG_ON check. Change this to be an ext4_warning so that we don't
crash the kernel.
In the Linux kernel, the following vulnerability has been resolved:
s390/dasd: Fix potential memleak in dasd_eckd_init()
`dasd_reserve_req` is allocated before `dasd_vol_info_req`, and it
also needs to be freed before the error returns, just like the other
cases in this function.
In the Linux kernel, the following vulnerability has been resolved:
fbdev: imxfb: Removed unneeded release_mem_region
Remove unnecessary release_mem_region from the error path to prevent
mem region from being released twice, which could avoid resource leak
or other unexpected issues.
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix potential memory leak in rtw_init_drv_sw()
In rtw_init_drv_sw(), there are various init functions are called to
populate the padapter structure and some checks for their return value.
However, except for the first one error path, the other five error paths
do not properly release the previous allocated resources, which leads to
various memory leaks.
This patch fixes them and keeps the success and error separate.
Note that these changes keep the form of `rtw_init_drv_sw()` in
"drivers/staging/r8188eu/os_dep/os_intfs.c". As there is no proper device
to test with, no runtime testing was performed.
In the Linux kernel, the following vulnerability has been resolved:
platform/chrome: cros_usbpd_notify: Fix error handling in cros_usbpd_notify_init()
The following WARNING message was given when rmmod cros_usbpd_notify:
Unexpected driver unregister!
WARNING: CPU: 0 PID: 253 at drivers/base/driver.c:270 driver_unregister+0x8a/0xb0
Modules linked in: cros_usbpd_notify(-)
CPU: 0 PID: 253 Comm: rmmod Not tainted 6.1.0-rc3 #24
...
Call Trace:
<TASK>
cros_usbpd_notify_exit+0x11/0x1e [cros_usbpd_notify]
__x64_sys_delete_module+0x3c7/0x570
? __ia32_sys_delete_module+0x570/0x570
? lock_is_held_type+0xe3/0x140
? syscall_enter_from_user_mode+0x17/0x50
? rcu_read_lock_sched_held+0xa0/0xd0
? syscall_enter_from_user_mode+0x1c/0x50
do_syscall_64+0x37/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f333fe9b1b7
The reason is that the cros_usbpd_notify_init() does not check the return
value of platform_driver_register(), and the cros_usbpd_notify can
install successfully even if platform_driver_register() failed.
Fix by checking the return value of platform_driver_register() and
unregister cros_usbpd_notify_plat_driver when it failed.
In the Linux kernel, the following vulnerability has been resolved:
scsi: lpfc: Fix null ndlp ptr dereference in abnormal exit path for GFT_ID
An error case exit from lpfc_cmpl_ct_cmd_gft_id() results in a call to
lpfc_nlp_put() with a null pointer to a nodelist structure.
Changed lpfc_cmpl_ct_cmd_gft_id() to initialize nodelist pointer upon
entry.
In the Linux kernel, the following vulnerability has been resolved:
fs/binfmt_elf: Fix memory leak in load_elf_binary()
There is a memory leak reported by kmemleak:
unreferenced object 0xffff88817104ef80 (size 224):
comm "xfs_admin", pid 47165, jiffies 4298708825 (age 1333.476s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
60 a8 b3 00 81 88 ff ff a8 10 5a 00 81 88 ff ff `.........Z.....
backtrace:
[<ffffffff819171e1>] __alloc_file+0x21/0x250
[<ffffffff81918061>] alloc_empty_file+0x41/0xf0
[<ffffffff81948cda>] path_openat+0xea/0x3d30
[<ffffffff8194ec89>] do_filp_open+0x1b9/0x290
[<ffffffff8192660e>] do_open_execat+0xce/0x5b0
[<ffffffff81926b17>] open_exec+0x27/0x50
[<ffffffff81a69250>] load_elf_binary+0x510/0x3ed0
[<ffffffff81927759>] bprm_execve+0x599/0x1240
[<ffffffff8192a997>] do_execveat_common.isra.0+0x4c7/0x680
[<ffffffff8192b078>] __x64_sys_execve+0x88/0xb0
[<ffffffff83bbf0a5>] do_syscall_64+0x35/0x80
If "interp_elf_ex" fails to allocate memory in load_elf_binary(),
the program will take the "out_free_ph" error handing path,
resulting in "interpreter" file resource is not released.
Fix it by adding an error handing path "out_free_file", which will
release the file resource when "interp_elf_ex" failed to allocate
memory.