| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ACPI: CPPC: Avoid out of bounds access when parsing _CPC data
If the NumEntries field in the _CPC return package is less than 2, do
not attempt to access the "Revision" element of that package, because
it may not be present then.
BugLink: https://lore.kernel.org/lkml/20220322143534.GC32582@xsang-OptiPlex-9020/ |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btmtksdio: Fix kernel oops in btmtksdio_interrupt
Fix the following kernel oops in btmtksdio_interrrupt
[ 14.339134] btmtksdio_interrupt+0x28/0x54
[ 14.339139] process_sdio_pending_irqs+0x68/0x1a0
[ 14.339144] sdio_irq_work+0x40/0x70
[ 14.339154] process_one_work+0x184/0x39c
[ 14.339160] worker_thread+0x228/0x3e8
[ 14.339168] kthread+0x148/0x3ac
[ 14.339176] ret_from_fork+0x10/0x30
That happened because hdev->power_on is already called before
sdio_set_drvdata which btmtksdio_interrupt handler relies on is not
properly set up.
The details are shown as the below: hci_register_dev would run
queue_work(hdev->req_workqueue, &hdev->power_on) as WQ_HIGHPRI
workqueue_struct to complete the power-on sequeunce and thus hci_power_on
may run before sdio_set_drvdata is done in btmtksdio_probe.
The hci_dev_do_open in hci_power_on would initialize the device and enable
the interrupt and thus it is possible that btmtksdio_interrupt is being
called right before sdio_set_drvdata is filled out.
When btmtksdio_interrupt is being called and sdio_set_drvdata is not filled
, the kernel oops is going to happen because btmtksdio_interrupt access an
uninitialized pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: Fix crash due to tcp_tsorted_anchor was initialized before release skb
Got crash when doing pressure test of mptcp:
===========================================================================
dst_release: dst:ffffa06ce6e5c058 refcnt:-1
kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
BUG: unable to handle kernel paging request at ffffa06ce6e5c058
PGD 190a01067 P4D 190a01067 PUD 43fffb067 PMD 22e403063 PTE 8000000226e5c063
Oops: 0011 [#1] SMP PTI
CPU: 7 PID: 7823 Comm: kworker/7:0 Kdump: loaded Tainted: G E
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.2.1 04/01/2014
Call Trace:
? skb_release_head_state+0x68/0x100
? skb_release_all+0xe/0x30
? kfree_skb+0x32/0xa0
? mptcp_sendmsg_frag+0x57e/0x750
? __mptcp_retrans+0x21b/0x3c0
? __switch_to_asm+0x35/0x70
? mptcp_worker+0x25e/0x320
? process_one_work+0x1a7/0x360
? worker_thread+0x30/0x390
? create_worker+0x1a0/0x1a0
? kthread+0x112/0x130
? kthread_flush_work_fn+0x10/0x10
? ret_from_fork+0x35/0x40
===========================================================================
In __mptcp_alloc_tx_skb skb was allocated and skb->tcp_tsorted_anchor will
be initialized, in under memory pressure situation sk_wmem_schedule will
return false and then kfree_skb. In this case skb->_skb_refdst is not null
because_skb_refdst and tcp_tsorted_anchor are stored in the same mem, and
kfree_skb will try to release dst and cause crash. |
| In the Linux kernel, the following vulnerability has been resolved:
af_netlink: Fix shift out of bounds in group mask calculation
When a netlink message is received, netlink_recvmsg() fills in the address
of the sender. One of the fields is the 32-bit bitfield nl_groups, which
carries the multicast group on which the message was received. The least
significant bit corresponds to group 1, and therefore the highest group
that the field can represent is 32. Above that, the UB sanitizer flags the
out-of-bounds shift attempts.
Which bits end up being set in such case is implementation defined, but
it's either going to be a wrong non-zero value, or zero, which is at least
not misleading. Make the latter choice deterministic by always setting to 0
for higher-numbered multicast groups.
To get information about membership in groups >= 32, userspace is expected
to use nl_pktinfo control messages[0], which are enabled by NETLINK_PKTINFO
socket option.
[0] https://lwn.net/Articles/147608/
The way to trigger this issue is e.g. through monitoring the BRVLAN group:
# bridge monitor vlan &
# ip link add name br type bridge
Which produces the following citation:
UBSAN: shift-out-of-bounds in net/netlink/af_netlink.c:162:19
shift exponent 32 is too large for 32-bit type 'int' |
| In the Linux kernel, the following vulnerability has been resolved:
net: dsa: fix panic on shutdown if multi-chip tree failed to probe
DSA probing is atypical because a tree of devices must probe all at
once, so out of N switches which call dsa_tree_setup_routing_table()
during probe, for (N - 1) of them, "complete" will return false and they
will exit probing early. The Nth switch will set up the whole tree on
their behalf.
The implication is that for (N - 1) switches, the driver binds to the
device successfully, without doing anything. When the driver is bound,
the ->shutdown() method may run. But if the Nth switch has failed to
initialize the tree, there is nothing to do for the (N - 1) driver
instances, since the slave devices have not been created, etc. Moreover,
dsa_switch_shutdown() expects that the calling @ds has been in fact
initialized, so it jumps at dereferencing the various data structures,
which is incorrect.
Avoid the ensuing NULL pointer dereferences by simply checking whether
the Nth switch has previously set "ds->setup = true" for the switch
which is currently shutting down. The entire setup is serialized under
dsa2_mutex which we already hold. |
| In the Linux kernel, the following vulnerability has been resolved:
mxser: fix xmit_buf leak in activate when LSR == 0xff
When LSR is 0xff in ->activate() (rather unlike), we return an error.
Provided ->shutdown() is not called when ->activate() fails, nothing
actually frees the buffer in this case.
Fix this by properly freeing the buffer in a designated label. We jump
there also from the "!info->type" if now too. |
| In the Linux kernel, the following vulnerability has been resolved:
remoteproc: qcom_q6v5_mss: Fix some leaks in q6v5_alloc_memory_region
The device_node pointer is returned by of_parse_phandle() or
of_get_child_by_name() with refcount incremented.
We should use of_node_put() on it when done.
This function only call of_node_put(node) when of_address_to_resource
succeeds, missing error cases. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on curseg->alloc_type
As Wenqing Liu reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215657
- Overview
UBSAN: array-index-out-of-bounds in fs/f2fs/segment.c:3460:2 when mount and operate a corrupted image
- Reproduce
tested on kernel 5.17-rc4, 5.17-rc6
1. mkdir test_crash
2. cd test_crash
3. unzip tmp2.zip
4. mkdir mnt
5. ./single_test.sh f2fs 2
- Kernel dump
[ 46.434454] loop0: detected capacity change from 0 to 131072
[ 46.529839] F2FS-fs (loop0): Mounted with checkpoint version = 7548c2d9
[ 46.738319] ================================================================================
[ 46.738412] UBSAN: array-index-out-of-bounds in fs/f2fs/segment.c:3460:2
[ 46.738475] index 231 is out of range for type 'unsigned int [2]'
[ 46.738539] CPU: 2 PID: 939 Comm: umount Not tainted 5.17.0-rc6 #1
[ 46.738547] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
[ 46.738551] Call Trace:
[ 46.738556] <TASK>
[ 46.738563] dump_stack_lvl+0x47/0x5c
[ 46.738581] ubsan_epilogue+0x5/0x50
[ 46.738592] __ubsan_handle_out_of_bounds+0x68/0x80
[ 46.738604] f2fs_allocate_data_block+0xdff/0xe60 [f2fs]
[ 46.738819] do_write_page+0xef/0x210 [f2fs]
[ 46.738934] f2fs_do_write_node_page+0x3f/0x80 [f2fs]
[ 46.739038] __write_node_page+0x2b7/0x920 [f2fs]
[ 46.739162] f2fs_sync_node_pages+0x943/0xb00 [f2fs]
[ 46.739293] f2fs_write_checkpoint+0x7bb/0x1030 [f2fs]
[ 46.739405] kill_f2fs_super+0x125/0x150 [f2fs]
[ 46.739507] deactivate_locked_super+0x60/0xc0
[ 46.739517] deactivate_super+0x70/0xb0
[ 46.739524] cleanup_mnt+0x11a/0x200
[ 46.739532] __cleanup_mnt+0x16/0x20
[ 46.739538] task_work_run+0x67/0xa0
[ 46.739547] exit_to_user_mode_prepare+0x18c/0x1a0
[ 46.739559] syscall_exit_to_user_mode+0x26/0x40
[ 46.739568] do_syscall_64+0x46/0xb0
[ 46.739584] entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is we missed to do sanity check on curseg->alloc_type,
result in out-of-bound accessing on sbi->block_count[] array, fix it. |
| In the Linux kernel, the following vulnerability has been resolved:
net: mana: Fix Rx DMA datasize and skb_over_panic
mana_get_rxbuf_cfg() aligns the RX buffer's DMA datasize to be
multiple of 64. So a packet slightly bigger than mtu+14, say 1536,
can be received and cause skb_over_panic.
Sample dmesg:
[ 5325.237162] skbuff: skb_over_panic: text:ffffffffc043277a len:1536 put:1536 head:ff1100018b517000 data:ff1100018b517100 tail:0x700 end:0x6ea dev:<NULL>
[ 5325.243689] ------------[ cut here ]------------
[ 5325.245748] kernel BUG at net/core/skbuff.c:192!
[ 5325.247838] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 5325.258374] RIP: 0010:skb_panic+0x4f/0x60
[ 5325.302941] Call Trace:
[ 5325.304389] <IRQ>
[ 5325.315794] ? skb_panic+0x4f/0x60
[ 5325.317457] ? asm_exc_invalid_op+0x1f/0x30
[ 5325.319490] ? skb_panic+0x4f/0x60
[ 5325.321161] skb_put+0x4e/0x50
[ 5325.322670] mana_poll+0x6fa/0xb50 [mana]
[ 5325.324578] __napi_poll+0x33/0x1e0
[ 5325.326328] net_rx_action+0x12e/0x280
As discussed internally, this alignment is not necessary. To fix
this bug, remove it from the code. So oversized packets will be
marked as CQE_RX_TRUNCATED by NIC, and dropped. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: firewire-lib: fix uninitialized flag for AV/C deferred transaction
AV/C deferred transaction was supported at a commit 00a7bb81c20f ("ALSA:
firewire-lib: Add support for deferred transaction") while 'deferrable'
flag can be uninitialized for non-control/notify AV/C transactions.
UBSAN reports it:
kernel: ================================================================================
kernel: UBSAN: invalid-load in /build/linux-aa0B4d/linux-5.15.0/sound/firewire/fcp.c:363:9
kernel: load of value 158 is not a valid value for type '_Bool'
kernel: CPU: 3 PID: 182227 Comm: irq/35-firewire Tainted: P OE 5.15.0-18-generic #18-Ubuntu
kernel: Hardware name: Gigabyte Technology Co., Ltd. AX370-Gaming 5/AX370-Gaming 5, BIOS F42b 08/01/2019
kernel: Call Trace:
kernel: <IRQ>
kernel: show_stack+0x52/0x58
kernel: dump_stack_lvl+0x4a/0x5f
kernel: dump_stack+0x10/0x12
kernel: ubsan_epilogue+0x9/0x45
kernel: __ubsan_handle_load_invalid_value.cold+0x44/0x49
kernel: fcp_response.part.0.cold+0x1a/0x2b [snd_firewire_lib]
kernel: fcp_response+0x28/0x30 [snd_firewire_lib]
kernel: fw_core_handle_request+0x230/0x3d0 [firewire_core]
kernel: handle_ar_packet+0x1d9/0x200 [firewire_ohci]
kernel: ? handle_ar_packet+0x1d9/0x200 [firewire_ohci]
kernel: ? transmit_complete_callback+0x9f/0x120 [firewire_core]
kernel: ar_context_tasklet+0xa8/0x2e0 [firewire_ohci]
kernel: tasklet_action_common.constprop.0+0xea/0xf0
kernel: tasklet_action+0x22/0x30
kernel: __do_softirq+0xd9/0x2e3
kernel: ? irq_finalize_oneshot.part.0+0xf0/0xf0
kernel: do_softirq+0x75/0xa0
kernel: </IRQ>
kernel: <TASK>
kernel: __local_bh_enable_ip+0x50/0x60
kernel: irq_forced_thread_fn+0x7e/0x90
kernel: irq_thread+0xba/0x190
kernel: ? irq_thread_fn+0x60/0x60
kernel: kthread+0x11e/0x140
kernel: ? irq_thread_check_affinity+0xf0/0xf0
kernel: ? set_kthread_struct+0x50/0x50
kernel: ret_from_fork+0x22/0x30
kernel: </TASK>
kernel: ================================================================================
This commit fixes the bug. The bug has no disadvantage for the non-
control/notify AV/C transactions since the flag has an effect for AV/C
response with INTERIM (0x0f) status which is not used for the transactions
in AV/C general specification. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: atmel: Fix error handling in snd_proto_probe
The device_node pointer is returned by of_parse_phandle() with refcount
incremented. We should use of_node_put() on it when done.
This function only calls of_node_put() in the regular path.
And it will cause refcount leak in error paths.
Fix this by calling of_node_put() in error handling too. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: rockchip: Fix PM usage reference of rockchip_i2s_tdm_resume
pm_runtime_get_sync will increment pm usage counter
even it failed. Forgetting to putting operation will
result in reference leak here. We fix it by replacing
it with pm_runtime_resume_and_get to keep usage counter
balanced. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: mediatek: mt8192-mt6359: Fix error handling in mt8192_mt6359_dev_probe
The device_node pointer is returned by of_parse_phandle() with refcount
incremented. We should use of_node_put() on it when done.
This function only calls of_node_put() in the regular path.
And it will cause refcount leak in error paths.
Fix this by calling of_node_put() in error handling too. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/msm/a3xx: fix error handling in a3xx_gpu_init()
These error paths returned 1 on failure, instead of a negative error
code. This would lead to an Oops in the caller. A second problem is
that the check for "if (ret != -ENODATA)" did not work because "ret" was
set to 1. |
| In the Linux kernel, the following vulnerability has been resolved:
net: dsa: Avoid cross-chip syncing of VLAN filtering
Changes to VLAN filtering are not applicable to cross-chip
notifications.
On a system like this:
.-----. .-----. .-----.
| sw1 +---+ sw2 +---+ sw3 |
'-1-2-' '-1-2-' '-1-2-'
Before this change, upon sw1p1 leaving a bridge, a call to
dsa_port_vlan_filtering would also be made to sw2p1 and sw3p1.
In this scenario:
.---------. .-----. .-----.
| sw1 +---+ sw2 +---+ sw3 |
'-1-2-3-4-' '-1-2-' '-1-2-'
When sw1p4 would leave a bridge, dsa_port_vlan_filtering would be
called for sw2 and sw3 with a non-existing port - leading to array
out-of-bounds accesses and crashes on mv88e6xxx. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix a btf decl_tag bug when tagging a function
syzbot reported a btf decl_tag bug with stack trace below:
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 3592 Comm: syz-executor914 Not tainted 5.16.0-syzkaller-11424-gb7892f7d5cb2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:btf_type_vlen include/linux/btf.h:231 [inline]
RIP: 0010:btf_decl_tag_resolve+0x83e/0xaa0 kernel/bpf/btf.c:3910
...
Call Trace:
<TASK>
btf_resolve+0x251/0x1020 kernel/bpf/btf.c:4198
btf_check_all_types kernel/bpf/btf.c:4239 [inline]
btf_parse_type_sec kernel/bpf/btf.c:4280 [inline]
btf_parse kernel/bpf/btf.c:4513 [inline]
btf_new_fd+0x19fe/0x2370 kernel/bpf/btf.c:6047
bpf_btf_load kernel/bpf/syscall.c:4039 [inline]
__sys_bpf+0x1cbb/0x5970 kernel/bpf/syscall.c:4679
__do_sys_bpf kernel/bpf/syscall.c:4738 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4736 [inline]
__x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:4736
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
The kasan error is triggered with an illegal BTF like below:
type 0: void
type 1: int
type 2: decl_tag to func type 3
type 3: func to func_proto type 8
The total number of types is 4 and the type 3 is illegal
since its func_proto type is out of range.
Currently, the target type of decl_tag can be struct/union, var or func.
Both struct/union and var implemented their own 'resolve' callback functions
and hence handled properly in kernel.
But func type doesn't have 'resolve' callback function. When
btf_decl_tag_resolve() tries to check func type, it tries to get
vlen of its func_proto type, which triggered the above kasan error.
To fix the issue, btf_decl_tag_resolve() needs to do btf_func_check()
before trying to accessing func_proto type.
In the current implementation, func type is checked with
btf_func_check() in the main checking function btf_check_all_types().
To fix the above kasan issue, let us implement 'resolve' callback
func type properly. The 'resolve' callback will be also called
in btf_check_all_types() for func types. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/bridge: anx7625: Fix overflow issue on reading EDID
The length of EDID block can be longer than 256 bytes, so we should use
`int` instead of `u8` for the `edid_pos` variable. |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix possible stall on recvmsg()
recvmsg() can enter an infinite loop if the caller provides the
MSG_WAITALL, the data present in the receive queue is not sufficient to
fulfill the request, and no more data is received by the peer.
When the above happens, mptcp_wait_data() will always return with
no wait, as the MPTCP_DATA_READY flag checked by such function is
set and never cleared in such code path.
Leveraging the above syzbot was able to trigger an RCU stall:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-...!: (10499 ticks this GP) idle=0af/1/0x4000000000000000 softirq=10678/10678 fqs=1
(t=10500 jiffies g=13089 q=109)
rcu: rcu_preempt kthread starved for 10497 jiffies! g13089 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:28696 pid: 14 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:4955 [inline]
__schedule+0x940/0x26f0 kernel/sched/core.c:6236
schedule+0xd3/0x270 kernel/sched/core.c:6315
schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955
rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8510 Comm: syz-executor827 Not tainted 5.15.0-rc2-next-20210920-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0xc8/0x180 mm/kasan/generic.c:189
Code: 38 00 74 ed 48 8d 50 08 eb 09 48 83 c0 01 48 39 d0 74 7a 80 38 00 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 <48> 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 80 38 00
RSP: 0018:ffffc9000cd676c8 EFLAGS: 00000283
RAX: ffffed100e9a110e RBX: ffffed100e9a110f RCX: ffffffff88ea062a
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888074d08870
RBP: ffffed100e9a110e R08: 0000000000000001 R09: ffff888074d08877
R10: ffffed100e9a110e R11: 0000000000000000 R12: ffff888074d08000
R13: ffff888074d08000 R14: ffff888074d08088 R15: ffff888074d08000
FS: 0000555556d8e300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
S: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000180 CR3: 0000000068909000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
test_and_clear_bit include/asm-generic/bitops/instrumented-atomic.h:83 [inline]
mptcp_release_cb+0x14a/0x210 net/mptcp/protocol.c:3016
release_sock+0xb4/0x1b0 net/core/sock.c:3204
mptcp_wait_data net/mptcp/protocol.c:1770 [inline]
mptcp_recvmsg+0xfd1/0x27b0 net/mptcp/protocol.c:2080
inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:659
sock_recvmsg_nosec net/socket.c:944 [inline]
____sys_recvmsg+0x527/0x600 net/socket.c:2626
___sys_recvmsg+0x127/0x200 net/socket.c:2670
do_recvmmsg+0x24d/0x6d0 net/socket.c:2764
__sys_recvmmsg net/socket.c:2843 [inline]
__do_sys_recvmmsg net/socket.c:2866 [inline]
__se_sys_recvmmsg net/socket.c:2859 [inline]
__x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2859
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc200d2
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/64s: Don't use DSISR for SLB faults
Since commit 46ddcb3950a2 ("powerpc/mm: Show if a bad page fault on data
is read or write.") we use page_fault_is_write(regs->dsisr) in
__bad_page_fault() to determine if the fault is for a read or write, and
change the message printed accordingly.
But SLB faults, aka Data Segment Interrupts, don't set DSISR (Data
Storage Interrupt Status Register) to a useful value. All ISA versions
from v2.03 through v3.1 specify that the Data Segment Interrupt sets
DSISR "to an undefined value". As far as I can see there's no mention of
SLB faults setting DSISR in any BookIV content either.
This manifests as accesses that should be a read being incorrectly
reported as writes, for example, using the xmon "dump" command:
0:mon> d 0x5deadbeef0000000
5deadbeef0000000
[359526.415354][ C6] BUG: Unable to handle kernel data access on write at 0x5deadbeef0000000
[359526.415611][ C6] Faulting instruction address: 0xc00000000010a300
cpu 0x6: Vector: 380 (Data SLB Access) at [c00000000ffbf400]
pc: c00000000010a300: mread+0x90/0x190
If we disassemble the PC, we see a load instruction:
0:mon> di c00000000010a300
c00000000010a300 89490000 lbz r10,0(r9)
We can also see in exceptions-64s.S that the data_access_slb block
doesn't set IDSISR=1, which means it doesn't load DSISR into pt_regs. So
the value we're using to determine if the fault is a read/write is some
stale value in pt_regs from a previous page fault.
Rework the printing logic to separate the SLB fault case out, and only
print read/write in the cases where we can determine it.
The result looks like eg:
0:mon> d 0x5deadbeef0000000
5deadbeef0000000
[ 721.779525][ C6] BUG: Unable to handle kernel data access at 0x5deadbeef0000000
[ 721.779697][ C6] Faulting instruction address: 0xc00000000014cbe0
cpu 0x6: Vector: 380 (Data SLB Access) at [c00000000ffbf390]
0:mon> d 0
0000000000000000
[ 742.793242][ C6] BUG: Kernel NULL pointer dereference at 0x00000000
[ 742.793316][ C6] Faulting instruction address: 0xc00000000014cbe0
cpu 0x6: Vector: 380 (Data SLB Access) at [c00000000ffbf390] |
| In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: Fix double uncharge the mem of sk_msg
If tcp_bpf_sendmsg is running during a tear down operation, psock may be
freed.
tcp_bpf_sendmsg()
tcp_bpf_send_verdict()
sk_msg_return()
tcp_bpf_sendmsg_redir()
unlikely(!psock))
sk_msg_free()
The mem of msg has been uncharged in tcp_bpf_send_verdict() by
sk_msg_return(), and would be uncharged by sk_msg_free() again. When psock
is null, we can simply returning an error code, this would then trigger
the sk_msg_free_nocharge in the error path of __SK_REDIRECT and would have
the side effect of throwing an error up to user space. This would be a
slight change in behavior from user side but would look the same as an
error if the redirect on the socket threw an error.
This issue can cause the following info:
WARNING: CPU: 0 PID: 2136 at net/ipv4/af_inet.c:155 inet_sock_destruct+0x13c/0x260
Call Trace:
<TASK>
__sk_destruct+0x24/0x1f0
sk_psock_destroy+0x19b/0x1c0
process_one_work+0x1b3/0x3c0
worker_thread+0x30/0x350
? process_one_work+0x3c0/0x3c0
kthread+0xe6/0x110
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x22/0x30
</TASK> |
