| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: Fix backlog accounting in qdisc_dequeue_internal
This issue applies for the following qdiscs: hhf, fq, fq_codel, and
fq_pie, and occurs in their change handlers when adjusting to the new
limit. The problem is the following in the values passed to the
subsequent qdisc_tree_reduce_backlog call given a tbf parent:
When the tbf parent runs out of tokens, skbs of these qdiscs will
be placed in gso_skb. Their peek handlers are qdisc_peek_dequeued,
which accounts for both qlen and backlog. However, in the case of
qdisc_dequeue_internal, ONLY qlen is accounted for when pulling
from gso_skb. This means that these qdiscs are missing a
qdisc_qstats_backlog_dec when dropping packets to satisfy the
new limit in their change handlers.
One can observe this issue with the following (with tc patched to
support a limit of 0):
export TARGET=fq
tc qdisc del dev lo root
tc qdisc add dev lo root handle 1: tbf rate 8bit burst 100b latency 1ms
tc qdisc replace dev lo handle 3: parent 1:1 $TARGET limit 1000
echo ''; echo 'add child'; tc -s -d qdisc show dev lo
ping -I lo -f -c2 -s32 -W0.001 127.0.0.1 2>&1 >/dev/null
echo ''; echo 'after ping'; tc -s -d qdisc show dev lo
tc qdisc change dev lo handle 3: parent 1:1 $TARGET limit 0
echo ''; echo 'after limit drop'; tc -s -d qdisc show dev lo
tc qdisc replace dev lo handle 2: parent 1:1 sfq
echo ''; echo 'post graft'; tc -s -d qdisc show dev lo
The second to last show command shows 0 packets but a positive
number (74) of backlog bytes. The problem becomes clearer in the
last show command, where qdisc_purge_queue triggers
qdisc_tree_reduce_backlog with the positive backlog and causes an
underflow in the tbf parent's backlog (4096 Mb instead of 0).
To fix this issue, the codepath for all clients of qdisc_dequeue_internal
has been simplified: codel, pie, hhf, fq, fq_pie, and fq_codel.
qdisc_dequeue_internal handles the backlog adjustments for all cases that
do not directly use the dequeue handler.
The old fq_codel_change limit adjustment loop accumulated the arguments to
the subsequent qdisc_tree_reduce_backlog call through the cstats field.
However, this is confusing and error prone as fq_codel_dequeue could also
potentially mutate this field (which qdisc_dequeue_internal calls in the
non gso_skb case), so we have unified the code here with other qdiscs. |
| In the Linux kernel, the following vulnerability has been resolved:
habanalabs: fix UAF in export_dmabuf()
As soon as we'd inserted a file reference into descriptor table, another
thread could close it. That's fine for the case when all we are doing is
returning that descriptor to userland (it's a race, but it's a userland
race and there's nothing the kernel can do about it). However, if we
follow fd_install() with any kind of access to objects that would be
destroyed on close (be it the struct file itself or anything destroyed
by its ->release()), we have a UAF.
dma_buf_fd() is a combination of reserving a descriptor and fd_install().
habanalabs export_dmabuf() calls it and then proceeds to access the
objects destroyed on close. In particular, it grabs an extra reference to
another struct file that will be dropped as part of ->release() for ours;
that "will be" is actually "might have already been".
Fix that by reserving descriptor before anything else and do fd_install()
only when everything had been set up. As a side benefit, we no longer
have the failure exit with file already created, but reference to
underlying file (as well as ->dmabuf_export_cnt, etc.) not grabbed yet;
unlike dma_buf_fd(), fd_install() can't fail. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: fix null pointer access
Writing a string without delimiters (' ', '\n', '\0') to the under
gpu_od/fan_ctrl sysfs or pp_power_profile_mode for the CUSTOM profile
will result in a null pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: Fix error code in iwl_op_mode_dvm_start()
Preserve the error code if iwl_setup_deferred_work() fails. The current
code returns ERR_PTR(0) (which is NULL) on this path. I believe the
missing error code potentially leads to a use after free involving
debugfs. |
| In the Linux kernel, the following vulnerability has been resolved:
rv: Use strings in da monitors tracepoints
Using DA monitors tracepoints with KASAN enabled triggers the following
warning:
BUG: KASAN: global-out-of-bounds in do_trace_event_raw_event_event_da_monitor+0xd6/0x1a0
Read of size 32 at addr ffffffffaada8980 by task ...
Call Trace:
<TASK>
[...]
do_trace_event_raw_event_event_da_monitor+0xd6/0x1a0
? __pfx_do_trace_event_raw_event_event_da_monitor+0x10/0x10
? trace_event_sncid+0x83/0x200
trace_event_sncid+0x163/0x200
[...]
The buggy address belongs to the variable:
automaton_snep+0x4e0/0x5e0
This is caused by the tracepoints reading 32 bytes __array instead of
__string from the automata definition. Such strings are literals and
reading 32 bytes ends up in out of bound memory accesses (e.g. the next
automaton's data in this case).
The error is harmless as, while printing the string, we stop at the null
terminator, but it should still be fixed.
Use the __string facilities while defining the tracepoints to avoid
reading out of bound memory. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: Pass ab pointer directly to ath12k_dp_tx_get_encap_type()
In ath12k_dp_tx_get_encap_type(), the arvif parameter is only used to
retrieve the ab pointer. In vdev delete sequence the arvif->ar could
become NULL and that would trigger kernel panic.
Since the caller ath12k_dp_tx() already has a valid ab pointer, pass it
directly to avoid panic and unnecessary dereferencing.
PC points to "ath12k_dp_tx+0x228/0x988 [ath12k]"
LR points to "ath12k_dp_tx+0xc8/0x988 [ath12k]".
The Backtrace obtained is as follows:
ath12k_dp_tx+0x228/0x988 [ath12k]
ath12k_mac_tx_check_max_limit+0x608/0x920 [ath12k]
ieee80211_process_measurement_req+0x320/0x348 [mac80211]
ieee80211_tx_dequeue+0x9ac/0x1518 [mac80211]
ieee80211_tx_dequeue+0xb14/0x1518 [mac80211]
ieee80211_tx_prepare_skb+0x224/0x254 [mac80211]
ieee80211_xmit+0xec/0x100 [mac80211]
__ieee80211_subif_start_xmit+0xc50/0xf40 [mac80211]
ieee80211_subif_start_xmit+0x2e8/0x308 [mac80211]
netdev_start_xmit+0x150/0x18c
dev_hard_start_xmit+0x74/0xc0
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1 |
| In the Linux kernel, the following vulnerability has been resolved:
drm/rockchip: vop2: fail cleanly if missing a primary plane for a video-port
Each window of a vop2 is usable by a specific set of video ports, so while
binding the vop2, we look through the list of available windows trying to
find one designated as primary-plane and usable by that specific port.
The code later wants to use drm_crtc_init_with_planes with that found
primary plane, but nothing has checked so far if a primary plane was
actually found.
For whatever reason, the rk3576 vp2 does not have a usable primary window
(if vp0 is also in use) which brought the issue to light and ended in a
null-pointer dereference further down.
As we expect a primary-plane to exist for a video-port, add a check at
the end of the window-iteration and fail probing if none was found. |
| In the Linux kernel, the following vulnerability has been resolved:
xen: fix UAF in dmabuf_exp_from_pages()
[dma_buf_fd() fixes; no preferences regarding the tree it goes through -
up to xen folks]
As soon as we'd inserted a file reference into descriptor table, another
thread could close it. That's fine for the case when all we are doing is
returning that descriptor to userland (it's a race, but it's a userland
race and there's nothing the kernel can do about it). However, if we
follow fd_install() with any kind of access to objects that would be
destroyed on close (be it the struct file itself or anything destroyed
by its ->release()), we have a UAF.
dma_buf_fd() is a combination of reserving a descriptor and fd_install().
gntdev dmabuf_exp_from_pages() calls it and then proceeds to access the
objects destroyed on close - starting with gntdev_dmabuf itself.
Fix that by doing reserving descriptor before anything else and do
fd_install() only when everything had been set up. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/hns: Fix double destruction of rsv_qp
rsv_qp may be double destroyed in error flow, first in free_mr_init(),
and then in hns_roce_exit(). Fix it by moving the free_mr_init() call
into hns_roce_v2_init().
list_del corruption, ffff589732eb9b50->next is LIST_POISON1 (dead000000000100)
WARNING: CPU: 8 PID: 1047115 at lib/list_debug.c:53 __list_del_entry_valid+0x148/0x240
...
Call trace:
__list_del_entry_valid+0x148/0x240
hns_roce_qp_remove+0x4c/0x3f0 [hns_roce_hw_v2]
hns_roce_v2_destroy_qp_common+0x1dc/0x5f4 [hns_roce_hw_v2]
hns_roce_v2_destroy_qp+0x22c/0x46c [hns_roce_hw_v2]
free_mr_exit+0x6c/0x120 [hns_roce_hw_v2]
hns_roce_v2_exit+0x170/0x200 [hns_roce_hw_v2]
hns_roce_exit+0x118/0x350 [hns_roce_hw_v2]
__hns_roce_hw_v2_init_instance+0x1c8/0x304 [hns_roce_hw_v2]
hns_roce_hw_v2_reset_notify_init+0x170/0x21c [hns_roce_hw_v2]
hns_roce_hw_v2_reset_notify+0x6c/0x190 [hns_roce_hw_v2]
hclge_notify_roce_client+0x6c/0x160 [hclge]
hclge_reset_rebuild+0x150/0x5c0 [hclge]
hclge_reset+0x10c/0x140 [hclge]
hclge_reset_subtask+0x80/0x104 [hclge]
hclge_reset_service_task+0x168/0x3ac [hclge]
hclge_service_task+0x50/0x100 [hclge]
process_one_work+0x250/0x9a0
worker_thread+0x324/0x990
kthread+0x190/0x210
ret_from_fork+0x10/0x18 |
| In the Linux kernel, the following vulnerability has been resolved:
HID: nintendo: avoid bluetooth suspend/resume stalls
Ensure we don't stall or panic the kernel when using bluetooth-connected
controllers. This was reported as an issue on android devices using
kernel 6.6 due to the resume hook which had been added for usb joycons.
First, set a new state value to JOYCON_CTLR_STATE_SUSPENDED in a
newly-added nintendo_hid_suspend. This makes sure we will not stall out
the kernel waiting for input reports during led classdev suspend. The
stalls could happen if connectivity is unreliable or lost to the
controller prior to suspend.
Second, since we lose connectivity during suspend, do not try
joycon_init() for bluetooth controllers in the nintendo_hid_resume path.
Tested via multiple suspend/resume flows when using the controller both
in USB and bluetooth modes. |
| In the Linux kernel, the following vulnerability has been resolved:
platform/x86/amd: pmf: Use device managed allocations
If setting up smart PC fails for any reason then this can lead to
a double free when unloading amd-pmf. This is because dev->buf was
freed but never set to NULL and is again freed in amd_pmf_remove().
To avoid subtle allocation bugs in failures leading to a double free
change all allocations into device managed allocations. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: fix GCC_GCC_PCIE_HOT_RST definition for WCN7850
GCC_GCC_PCIE_HOT_RST is wrongly defined for WCN7850, causing kernel crash
on some specific platforms.
Since this register is divergent for WCN7850 and QCN9274, move it to
register table to allow different definitions. Then correct the register
address for WCN7850 to fix this issue.
Note IPQ5332 is not affected as it is not PCIe based device.
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3 |
| In the Linux kernel, the following vulnerability has been resolved:
s390/mm: Fix in_atomic() handling in do_secure_storage_access()
Kernel user spaces accesses to not exported pages in atomic context
incorrectly try to resolve the page fault.
With debug options enabled call traces like this can be seen:
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1523
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 419074, name: qemu-system-s39
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
INFO: lockdep is turned off.
Preemption disabled at:
[<00000383ea47cfa2>] copy_page_from_iter_atomic+0xa2/0x8a0
CPU: 12 UID: 0 PID: 419074 Comm: qemu-system-s39
Tainted: G W 6.16.0-20250531.rc0.git0.69b3a602feac.63.fc42.s390x+debug #1 PREEMPT
Tainted: [W]=WARN
Hardware name: IBM 3931 A01 703 (LPAR)
Call Trace:
[<00000383e990d282>] dump_stack_lvl+0xa2/0xe8
[<00000383e99bf152>] __might_resched+0x292/0x2d0
[<00000383eaa7c374>] down_read+0x34/0x2d0
[<00000383e99432f8>] do_secure_storage_access+0x108/0x360
[<00000383eaa724b0>] __do_pgm_check+0x130/0x220
[<00000383eaa842e4>] pgm_check_handler+0x114/0x160
[<00000383ea47d028>] copy_page_from_iter_atomic+0x128/0x8a0
([<00000383ea47d016>] copy_page_from_iter_atomic+0x116/0x8a0)
[<00000383e9c45eae>] generic_perform_write+0x16e/0x310
[<00000383e9eb87f4>] ext4_buffered_write_iter+0x84/0x160
[<00000383e9da0de4>] vfs_write+0x1c4/0x460
[<00000383e9da123c>] ksys_write+0x7c/0x100
[<00000383eaa7284e>] __do_syscall+0x15e/0x280
[<00000383eaa8417e>] system_call+0x6e/0x90
INFO: lockdep is turned off.
It is not allowed to take the mmap_lock while in atomic context. Therefore
handle such a secure storage access fault as if the accessed page is not
mapped: the uaccess function will return -EFAULT, and the caller has to
deal with this. Usually this means that the access is retried in process
context, which allows to resolve the page fault (or in this case export the
page). |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: fix invalid access to memory
In ath12k_dp_rx_msdu_coalesce(), rxcb is fetched from skb and boolean
is_continuation is part of rxcb.
Currently, after freeing the skb, the rxcb->is_continuation accessed
again which is wrong since the memory is already freed.
This might lead use-after-free error.
Hence, fix by locally defining bool is_continuation from rxcb,
so that after freeing skb, is_continuation can be used.
Compile tested only. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw89: pci: configure manual DAC mode via PCI config API only
To support 36-bit DMA, configure chip proprietary bit via PCI config API
or chip DBI interface. However, the PCI device mmap isn't set yet and
the DBI is also inaccessible via mmap, so only if the bit can be accessible
via PCI config API, chip can support 36-bit DMA. Otherwise, fallback to
32-bit DMA.
With NULL mmap address, kernel throws trace:
BUG: unable to handle page fault for address: 0000000000001090
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: Oops: 0002 [#1] PREEMPT SMP PTI
CPU: 1 UID: 0 PID: 71 Comm: irq/26-pciehp Tainted: G OE 6.14.2-061402-generic #202504101348
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
RIP: 0010:rtw89_pci_ops_write16+0x12/0x30 [rtw89_pci]
RSP: 0018:ffffb0ffc0acf9d8 EFLAGS: 00010206
RAX: ffffffffc158f9c0 RBX: ffff94865e702020 RCX: 0000000000000000
RDX: 0000000000000718 RSI: 0000000000001090 RDI: ffff94865e702020
RBP: ffffb0ffc0acf9d8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000015
R13: 0000000000000719 R14: ffffb0ffc0acfa1f R15: ffffffffc1813060
FS: 0000000000000000(0000) GS:ffff9486f3480000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000001090 CR3: 0000000090440001 CR4: 00000000000626f0
Call Trace:
<TASK>
rtw89_pci_read_config_byte+0x6d/0x120 [rtw89_pci]
rtw89_pci_cfg_dac+0x5b/0xb0 [rtw89_pci]
rtw89_pci_probe+0xa96/0xbd0 [rtw89_pci]
? __pfx___device_attach_driver+0x10/0x10
? __pfx___device_attach_driver+0x10/0x10
local_pci_probe+0x47/0xa0
pci_call_probe+0x5d/0x190
pci_device_probe+0xa7/0x160
really_probe+0xf9/0x370
? pm_runtime_barrier+0x55/0xa0
__driver_probe_device+0x8c/0x140
driver_probe_device+0x24/0xd0
__device_attach_driver+0xcd/0x170
bus_for_each_drv+0x99/0x100
__device_attach+0xb4/0x1d0
device_attach+0x10/0x20
pci_bus_add_device+0x59/0x90
pci_bus_add_devices+0x31/0x80
pciehp_configure_device+0xaa/0x170
pciehp_enable_slot+0xd6/0x240
pciehp_handle_presence_or_link_change+0xf1/0x180
pciehp_ist+0x162/0x1c0
irq_thread_fn+0x24/0x70
irq_thread+0xef/0x1c0
? __pfx_irq_thread_fn+0x10/0x10
? __pfx_irq_thread_dtor+0x10/0x10
? __pfx_irq_thread+0x10/0x10
kthread+0xfc/0x230
? __pfx_kthread+0x10/0x10
ret_from_fork+0x47/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Do not include stack ptr register in precision backtracking bookkeeping
Yi Lai reported an issue ([1]) where the following warning appears
in kernel dmesg:
[ 60.643604] verifier backtracking bug
[ 60.643635] WARNING: CPU: 10 PID: 2315 at kernel/bpf/verifier.c:4302 __mark_chain_precision+0x3a6c/0x3e10
[ 60.648428] Modules linked in: bpf_testmod(OE)
[ 60.650471] CPU: 10 UID: 0 PID: 2315 Comm: test_progs Tainted: G OE 6.15.0-rc4-gef11287f8289-dirty #327 PREEMPT(full)
[ 60.654385] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
[ 60.656682] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[ 60.660475] RIP: 0010:__mark_chain_precision+0x3a6c/0x3e10
[ 60.662814] Code: 5a 30 84 89 ea e8 c4 d9 01 00 80 3d 3e 7d d8 04 00 0f 85 60 fa ff ff c6 05 31 7d d8 04
01 48 c7 c7 00 58 30 84 e8 c4 06 a5 ff <0f> 0b e9 46 fa ff ff 48 ...
[ 60.668720] RSP: 0018:ffff888116cc7298 EFLAGS: 00010246
[ 60.671075] RAX: 54d70e82dfd31900 RBX: ffff888115b65e20 RCX: 0000000000000000
[ 60.673659] RDX: 0000000000000001 RSI: 0000000000000004 RDI: 00000000ffffffff
[ 60.676241] RBP: 0000000000000400 R08: ffff8881f6f23bd3 R09: 1ffff1103ede477a
[ 60.678787] R10: dffffc0000000000 R11: ffffed103ede477b R12: ffff888115b60ae8
[ 60.681420] R13: 1ffff11022b6cbc4 R14: 00000000fffffff2 R15: 0000000000000001
[ 60.684030] FS: 00007fc2aedd80c0(0000) GS:ffff88826fa8a000(0000) knlGS:0000000000000000
[ 60.686837] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.689027] CR2: 000056325369e000 CR3: 000000011088b002 CR4: 0000000000370ef0
[ 60.691623] Call Trace:
[ 60.692821] <TASK>
[ 60.693960] ? __pfx_verbose+0x10/0x10
[ 60.695656] ? __pfx_disasm_kfunc_name+0x10/0x10
[ 60.697495] check_cond_jmp_op+0x16f7/0x39b0
[ 60.699237] do_check+0x58fa/0xab10
...
Further analysis shows the warning is at line 4302 as below:
4294 /* static subprog call instruction, which
4295 * means that we are exiting current subprog,
4296 * so only r1-r5 could be still requested as
4297 * precise, r0 and r6-r10 or any stack slot in
4298 * the current frame should be zero by now
4299 */
4300 if (bt_reg_mask(bt) & ~BPF_REGMASK_ARGS) {
4301 verbose(env, "BUG regs %x\n", bt_reg_mask(bt));
4302 WARN_ONCE(1, "verifier backtracking bug");
4303 return -EFAULT;
4304 }
With the below test (also in the next patch):
__used __naked static void __bpf_jmp_r10(void)
{
asm volatile (
"r2 = 2314885393468386424 ll;"
"goto +0;"
"if r2 <= r10 goto +3;"
"if r1 >= -1835016 goto +0;"
"if r2 <= 8 goto +0;"
"if r3 <= 0 goto +0;"
"exit;"
::: __clobber_all);
}
SEC("?raw_tp")
__naked void bpf_jmp_r10(void)
{
asm volatile (
"r3 = 0 ll;"
"call __bpf_jmp_r10;"
"r0 = 0;"
"exit;"
::: __clobber_all);
}
The following is the verifier failure log:
0: (18) r3 = 0x0 ; R3_w=0
2: (85) call pc+2
caller:
R10=fp0
callee:
frame1: R1=ctx() R3_w=0 R10=fp0
5: frame1: R1=ctx() R3_w=0 R10=fp0
; asm volatile (" \ @ verifier_precision.c:184
5: (18) r2 = 0x20202000256c6c78 ; frame1: R2_w=0x20202000256c6c78
7: (05) goto pc+0
8: (bd) if r2 <= r10 goto pc+3 ; frame1: R2_w=0x20202000256c6c78 R10=fp0
9: (35) if r1 >= 0xffe3fff8 goto pc+0 ; frame1: R1=ctx()
10: (b5) if r2 <= 0x8 goto pc+0
mark_precise: frame1: last_idx 10 first_idx 0 subseq_idx -1
mark_precise: frame1: regs=r2 stack= before 9: (35) if r1 >= 0xffe3fff8 goto pc+0
mark_precise: frame1: regs=r2 stack= before 8: (bd) if r2 <= r10 goto pc+3
mark_preci
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net: dsa: b53: do not enable EEE on bcm63xx
BCM63xx internal switches do not support EEE, but provide multiple RGMII
ports where external PHYs may be connected. If one of these PHYs are EEE
capable, we may try to enable EEE for the MACs, which then hangs the
system on access of the (non-existent) EEE registers.
Fix this by checking if the switch actually supports EEE before
attempting to configure it. |
| In the Linux kernel, the following vulnerability has been resolved:
nvme-tcp: sanitize request list handling
Validate the request in nvme_tcp_handle_r2t() to ensure it's not part of
any list, otherwise a malicious R2T PDU might inject a loop in request
list processing. |
| In the Linux kernel, the following vulnerability has been resolved:
riscv: save the SR_SUM status over switches
When threads/tasks are switched we need to ensure the old execution's
SR_SUM state is saved and the new thread has the old SR_SUM state
restored.
The issue was seen under heavy load especially with the syz-stress tool
running, with crashes as follows in schedule_tail:
Unable to handle kernel access to user memory without uaccess routines
at virtual address 000000002749f0d0
Oops [#1]
Modules linked in:
CPU: 1 PID: 4875 Comm: syz-executor.0 Not tainted
5.12.0-rc2-syzkaller-00467-g0d7588ab9ef9 #0
Hardware name: riscv-virtio,qemu (DT)
epc : schedule_tail+0x72/0xb2 kernel/sched/core.c:4264
ra : task_pid_vnr include/linux/sched.h:1421 [inline]
ra : schedule_tail+0x70/0xb2 kernel/sched/core.c:4264
epc : ffffffe00008c8b0 ra : ffffffe00008c8ae sp : ffffffe025d17ec0
gp : ffffffe005d25378 tp : ffffffe00f0d0000 t0 : 0000000000000000
t1 : 0000000000000001 t2 : 00000000000f4240 s0 : ffffffe025d17ee0
s1 : 000000002749f0d0 a0 : 000000000000002a a1 : 0000000000000003
a2 : 1ffffffc0cfac500 a3 : ffffffe0000c80cc a4 : 5ae9db91c19bbe00
a5 : 0000000000000000 a6 : 0000000000f00000 a7 : ffffffe000082eba
s2 : 0000000000040000 s3 : ffffffe00eef96c0 s4 : ffffffe022c77fe0
s5 : 0000000000004000 s6 : ffffffe067d74e00 s7 : ffffffe067d74850
s8 : ffffffe067d73e18 s9 : ffffffe067d74e00 s10: ffffffe00eef96e8
s11: 000000ae6cdf8368 t3 : 5ae9db91c19bbe00 t4 : ffffffc4043cafb2
t5 : ffffffc4043cafba t6 : 0000000000040000
status: 0000000000000120 badaddr: 000000002749f0d0 cause:
000000000000000f
Call Trace:
[<ffffffe00008c8b0>] schedule_tail+0x72/0xb2 kernel/sched/core.c:4264
[<ffffffe000005570>] ret_from_exception+0x0/0x14
Dumping ftrace buffer:
(ftrace buffer empty)
---[ end trace b5f8f9231dc87dda ]---
The issue comes from the put_user() in schedule_tail
(kernel/sched/core.c) doing the following:
asmlinkage __visible void schedule_tail(struct task_struct *prev)
{
...
if (current->set_child_tid)
put_user(task_pid_vnr(current), current->set_child_tid);
...
}
the put_user() macro causes the code sequence to come out as follows:
1: __enable_user_access()
2: reg = task_pid_vnr(current);
3: *current->set_child_tid = reg;
4: __disable_user_access()
The problem is that we may have a sleeping function as argument which
could clear SR_SUM causing the panic above. This was fixed by
evaluating the argument of the put_user() macro outside the user-enabled
section in commit 285a76bb2cf5 ("riscv: evaluate put_user() arg before
enabling user access")"
In order for riscv to take advantage of unsafe_get/put_XXX() macros and
to avoid the same issue we had with put_user() and sleeping functions we
must ensure code flow can go through switch_to() from within a region of
code with SR_SUM enabled and come back with SR_SUM still enabled. This
patch addresses the problem allowing future work to enable full use of
unsafe_get/put_XXX() macros without needing to take a CSR bit flip cost
on every access. Make switch_to() save and restore SR_SUM. |
| In the Linux kernel, the following vulnerability has been resolved:
mm: fix uprobe pte be overwritten when expanding vma
Patch series "Fix uprobe pte be overwritten when expanding vma".
This patch (of 4):
We encountered a BUG alert triggered by Syzkaller as follows:
BUG: Bad rss-counter state mm:00000000b4a60fca type:MM_ANONPAGES val:1
And we can reproduce it with the following steps:
1. register uprobe on file at zero offset
2. mmap the file at zero offset:
addr1 = mmap(NULL, 2 * 4096, PROT_NONE, MAP_PRIVATE, fd, 0);
3. mremap part of vma1 to new vma2:
addr2 = mremap(addr1, 4096, 2 * 4096, MREMAP_MAYMOVE);
4. mremap back to orig addr1:
mremap(addr2, 4096, 4096, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
In step 3, the vma1 range [addr1, addr1 + 4096] will be remap to new vma2
with range [addr2, addr2 + 8192], and remap uprobe anon page from the vma1
to vma2, then unmap the vma1 range [addr1, addr1 + 4096].
In step 4, the vma2 range [addr2, addr2 + 4096] will be remap back to the
addr range [addr1, addr1 + 4096]. Since the addr range [addr1 + 4096,
addr1 + 8192] still maps the file, it will take vma_merge_new_range to
expand the range, and then do uprobe_mmap in vma_complete. Since the
merged vma pgoff is also zero offset, it will install uprobe anon page to
the merged vma. However, the upcomming move_page_tables step, which use
set_pte_at to remap the vma2 uprobe pte to the merged vma, will overwrite
the newly uprobe pte in the merged vma, and lead that pte to be orphan.
Since the uprobe pte will be remapped to the merged vma, we can remove the
unnecessary uprobe_mmap upon merged vma.
This problem was first found in linux-6.6.y and also exists in the
community syzkaller:
https://lore.kernel.org/all/000000000000ada39605a5e71711@google.com/T/ |
