In the Linux kernel, the following vulnerability has been resolved:
drm/xe/pf: Fix sysfs initialization
In case of devm_add_action_or_reset() failure the provided cleanup
action will be run immediately on the not yet initialized kobject.
This may lead to errors like:
[ ] kobject: '(null)' (ff110001393608e0): is not initialized, yet kobject_put() is being called.
[ ] WARNING: lib/kobject.c:734 at kobject_put+0xd9/0x250, CPU#0: kworker/0:0/9
[ ] RIP: 0010:kobject_put+0xdf/0x250
[ ] Call Trace:
[ ] xe_sriov_pf_sysfs_init+0x21/0x100 [xe]
[ ] xe_sriov_pf_init_late+0x87/0x2b0 [xe]
[ ] xe_sriov_init_late+0x5f/0x2c0 [xe]
[ ] xe_device_probe+0x5f2/0xc20 [xe]
[ ] xe_pci_probe+0x396/0x610 [xe]
[ ] local_pci_probe+0x47/0xb0
[ ] refcount_t: underflow; use-after-free.
[ ] WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x68/0xb0, CPU#0: kworker/0:0/9
[ ] RIP: 0010:refcount_warn_saturate+0x68/0xb0
[ ] Call Trace:
[ ] kobject_put+0x174/0x250
[ ] xe_sriov_pf_sysfs_init+0x21/0x100 [xe]
[ ] xe_sriov_pf_init_late+0x87/0x2b0 [xe]
[ ] xe_sriov_init_late+0x5f/0x2c0 [xe]
[ ] xe_device_probe+0x5f2/0xc20 [xe]
[ ] xe_pci_probe+0x396/0x610 [xe]
[ ] local_pci_probe+0x47/0xb0
Fix that by calling kobject_init() and kobject_add() separately
and register cleanup action after the kobject is initialized.
Also make this cleanup registration a part of the create helper to
fix another mistake, as in the loop we were wrongly passing parent
kobject while registering cleanup action, and this resulted in some
undetected leaks.
(cherry picked from commit 98b16727f07e26a5d4de84d88805ce7ffcfdd324)
In the Linux kernel, the following vulnerability has been resolved:
pstore/ram: fix buffer overflow in persistent_ram_save_old()
persistent_ram_save_old() can be called multiple times for the same
persistent_ram_zone (e.g., via ramoops_pstore_read -> ramoops_get_next_prz
for PSTORE_TYPE_DMESG records).
Currently, the function only allocates prz->old_log when it is NULL,
but it unconditionally updates prz->old_log_size to the current buffer
size and then performs memcpy_fromio() using this new size. If the
buffer size has grown since the first allocation (which can happen
across different kernel boot cycles), this leads to:
1. A heap buffer overflow (OOB write) in the memcpy_fromio() calls
2. A subsequent OOB read when ramoops_pstore_read() accesses the buffer
using the incorrect (larger) old_log_size
The KASAN splat would look similar to:
BUG: KASAN: slab-out-of-bounds in ramoops_pstore_read+0x...
Read of size N at addr ... by task ...
The conditions are likely extremely hard to hit:
0. Crash with a ramoops write of less-than-record-max-size bytes.
1. Reboot: ramoops registers, pstore_get_records(0) reads old crash,
allocates old_log with size X
2. Crash handler registered, timer started (if pstore_update_ms >= 0)
3. Oops happens (non-fatal, system continues)
4. pstore_dump() writes oops via ramoops_pstore_write() size Y (>X)
5. pstore_new_entry = 1, pstore_timer_kick() called
6. System continues running (not a panic oops)
7. Timer fires after pstore_update_ms milliseconds
8. pstore_timefunc() → schedule_work() → pstore_dowork() → pstore_get_records(1)
9. ramoops_get_next_prz() → persistent_ram_save_old()
10. buffer_size() returns Y, but old_log is X bytes
11. Y > X: memcpy_fromio() overflows heap
Requirements:
- a prior crash record exists that did not fill the record size
(almost impossible since the crash handler writes as much as it
can possibly fit into the record, capped by max record size and
the kmsg buffer almost always exceeds the max record size)
- pstore_update_ms >= 0 (disabled by default)
- Non-fatal oops (system survives)
Free and reallocate the buffer when the new size differs from the
previously allocated size. This ensures old_log always has sufficient
space for the data being copied.
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: fsl-edma: don't explicitly disable clocks in .remove()
The clocks in fsl_edma_engine::muxclk are allocated and enabled with
devm_clk_get_enabled(), which automatically cleans these resources up,
but these clocks are also manually disabled in fsl_edma_remove(). This
causes warnings on driver removal for each clock:
edma_module already disabled
WARNING: CPU: 0 PID: 418 at drivers/clk/clk.c:1200 clk_core_disable+0x198/0x1c8
[...]
Call trace:
clk_core_disable+0x198/0x1c8 (P)
clk_disable+0x34/0x58
fsl_edma_remove+0x74/0xe8 [fsl_edma]
[...]
---[ end trace 0000000000000000 ]---
edma_module already unprepared
WARNING: CPU: 0 PID: 418 at drivers/clk/clk.c:1059 clk_core_unprepare+0x1f8/0x220
[...]
Call trace:
clk_core_unprepare+0x1f8/0x220 (P)
clk_unprepare+0x34/0x58
fsl_edma_remove+0x7c/0xe8 [fsl_edma]
[...]
---[ end trace 0000000000000000 ]---
Fix these warnings by removing the unnecessary fsl_disable_clocks() call
in fsl_edma_remove().
In the Linux kernel, the following vulnerability has been resolved:
NFS/localio: prevent direct reclaim recursion into NFS via nfs_writepages
LOCALIO is an NFS loopback mount optimization that avoids using the
network for READ, WRITE and COMMIT if the NFS client and server are
determined to be on the same system. But because LOCALIO is still
fundamentally "just NFS loopback mount" it is susceptible to recursion
deadlock via direct reclaim, e.g.: NFS LOCALIO down to XFS and then
back into NFS via nfs_writepages.
Fix LOCALIO's potential for direct reclaim deadlock by ensuring that
all its page cache allocations are done from GFP_NOFS context.
Thanks to Ben Coddington for pointing out commit ad22c7a043c2 ("xfs:
prevent stack overflows from page cache allocation").
In the Linux kernel, the following vulnerability has been resolved:
clocksource/drivers/timer-sp804: Fix an Oops when read_current_timer is called on ARM32 platforms where the SP804 is not registered as the sched_clock.
On SP804, the delay timer shares the same clkevt instance with
sched_clock. On some platforms, when
sp804_clocksource_and_sched_clock_init is called with use_sched_clock
not set to 1, sched_clkevt is not properly initialized. However,
sp804_register_delay_timer is invoked unconditionally, and
read_current_timer() subsequently calls sp804_read on an uninitialized
sched_clkevt, leading to a kernel Oops when accessing
sched_clkevt->value.
Declare a dedicated clkevt instance exclusively for delay timer,
instead of sharing the same clkevt with sched_clock. This ensures
that read_current_timer continues to work correctly regardless of
whether SP804 is selected as the sched_clock.
In the Linux kernel, the following vulnerability has been resolved:
gpio: cdev: Avoid NULL dereference in linehandle_create()
In linehandle_create(), there is a statement like this:
retain_and_null_ptr(lh);
Soon after, there is a debug printout that dereferences "lh", which
will crash things.
Avoid the crash by using handlereq.lines, which is the same value.
In the Linux kernel, the following vulnerability has been resolved:
procfs: fix missing RCU protection when reading real_parent in do_task_stat()
When reading /proc/[pid]/stat, do_task_stat() accesses task->real_parent
without proper RCU protection, which leads to:
cpu 0 cpu 1
----- -----
do_task_stat
var = task->real_parent
release_task
call_rcu(delayed_put_task_struct)
task_tgid_nr_ns(var)
rcu_read_lock <--- Too late to protect task->real_parent!
task_pid_ptr <--- UAF!
rcu_read_unlock
This patch uses task_ppid_nr_ns() instead of task_tgid_nr_ns() to add
proper RCU protection for accessing task->real_parent.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: clear stale link mapping of ahvif->links_map
When an arvif is initialized in non-AP STA mode but MLO connection
preparation fails before the arvif is created
(arvif->is_created remains false), the error path attempts to delete all
links. However, link deletion only executes when arvif->is_created is true.
As a result, ahvif retains a stale entry of arvif that is initialized but
not created.
When a new arvif is initialized with the same link id, this stale mapping
triggers the following WARN_ON.
WARNING: drivers/net/wireless/ath/ath12k/mac.c:4271 at ath12k_mac_op_change_vif_links+0x140/0x180 [ath12k], CPU#3: wpa_supplicant/275
Call trace:
ath12k_mac_op_change_vif_links+0x140/0x180 [ath12k] (P)
drv_change_vif_links+0xbc/0x1a4 [mac80211]
ieee80211_vif_update_links+0x54c/0x6a0 [mac80211]
ieee80211_vif_set_links+0x40/0x70 [mac80211]
ieee80211_prep_connection+0x84/0x450 [mac80211]
ieee80211_mgd_auth+0x200/0x480 [mac80211]
ieee80211_auth+0x14/0x20 [mac80211]
cfg80211_mlme_auth+0x90/0xf0 [cfg80211]
nl80211_authenticate+0x32c/0x380 [cfg80211]
genl_family_rcv_msg_doit+0xc8/0x134
Fix this issue by unassigning the link vif and clearing ahvif->links_map
if arvif is only initialized but not created.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.5-01651-QCAHKSWPL_SILICONZ-1
In the Linux kernel, the following vulnerability has been resolved:
octeontx2-af: Fix PF driver crash with kexec kernel booting
During a kexec reboot the hardware is not power-cycled, so AF state from
the old kernel can persist into the new kernel. When AF and PF drivers
are built as modules, the PF driver may probe before AF reinitializes
the hardware.
The PF driver treats the RVUM block revision as an indication that AF
initialization is complete. If this value is left uncleared at shutdown,
PF may incorrectly assume AF is ready and access stale hardware state,
leading to a crash.
Clear the RVUM block revision during AF shutdown to avoid PF
mis-detecting AF readiness after kexec.