In the Linux kernel, the following vulnerability has been resolved:
i2c: qcom-cci: Fix NULL pointer dereference in cci_remove()
On all modern platforms Qualcomm CCI controller provides two I2C masters,
and on particular boards only one I2C master may be initialized, and in
such cases the device unbinding or driver removal causes a NULL pointer
dereference, because cci_halt() is called for all two I2C masters, but
a completion is initialized only for the single enabled master:
% rmmod i2c-qcom-cci
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
<snip>
Call trace:
__wait_for_common+0x194/0x1a8 (P)
wait_for_completion_timeout+0x20/0x2c
cci_remove+0xc4/0x138 [i2c_qcom_cci]
platform_remove+0x20/0x30
device_remove+0x4c/0x80
device_release_driver_internal+0x1c8/0x224
driver_detach+0x50/0x98
bus_remove_driver+0x6c/0xbc
driver_unregister+0x30/0x60
platform_driver_unregister+0x14/0x20
qcom_cci_driver_exit+0x18/0x1008 [i2c_qcom_cci]
....
In the Linux kernel, the following vulnerability has been resolved:
debugobjects: Do not fill_pool() if pi_blocked_on
On RT enabled kernels, fill_pool() ends up calling rtlock_lock(), which
asserts if current::pi_blocked_on is set, because a task can obviously only
block on one lock as otherwise the priority inheritenace chain gets
corrupted.
Prevent this by expanding the conditional to take current::pi_blocked_on
into account.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Use krealloc_array() in dal_vector_reserve()
[Why & How]
dal_vector_reserve() computes the allocation size as
"capacity * vector->struct_size" using uint32_t arithmetic, which can
silently wrap to a small value on overflow. This would cause krealloc to
return a smaller buffer than expected, leading to heap overflows on
subsequent vector appends.
Replace krealloc() with krealloc_array() which performs an internal
overflow check and returns NULL on wrap, preventing the issue.
(cherry picked from commit 37668568641ccc4cc1dbca4923d0a16609dd5707)
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix out-of-bounds read in dp_get_eq_aux_rd_interval()
[Why & How]
The aux_rd_interval array in struct dc_lttpr_caps is declared with
MAX_REPEATER_CNT - 1 (7) elements, indexed 0..6. However, the offset
parameter passed to dp_get_eq_aux_rd_interval() can be as large as
MAX_REPEATER_CNT (8) when a sink reports 8 LTTPR repeaters via DPCD.
This leads to an out-of-bounds read of aux_rd_interval[7] when offset
is 8.
Fix this by growing aux_rd_interval to MAX_REPEATER_CNT elements to
accommodate the full range of valid repeater counts defined by the DP
spec.
(cherry picked from commit a55a458a8df37a65ffda5cf721d554a8f74f6b04)
In the Linux kernel, the following vulnerability has been resolved:
slimbus: qcom-ngd-ctrl: Avoid ABBA on tx_lock/ctrl->lock
During the SSR/PDR down notification the tx_lock is taken with the
intent to provide synchronization with active DMA transfers.
But during this period qcom_slim_ngd_down() is invoked, which ends up in
slim_report_absent(), which takes the slim_controller lock. In multiple
other codepaths these two locks are taken in the opposite order (i.e.
slim_controller then tx_lock).
The result is a lockdep splat, and a possible deadlock:
rprocctl/449 is trying to acquire lock:
ffff00009793e620 (&ctrl->lock){+.+.}-{4:4}, at: slim_report_absent (drivers/slimbus/core.c:322) slimbus
but task is already holding lock:
ffff00009793fb50 (&ctrl->tx_lock){+.+.}-{4:4}, at: qcom_slim_ngd_ssr_pdr_notify (drivers/slimbus/qcom-ngd-ctrl.c:1475) slim_qcom_ngd_ctrl
which lock already depends on the new lock.
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ctrl->tx_lock);
lock(&ctrl->lock);
lock(&ctrl->tx_lock);
lock(&ctrl->lock);
The assumption is that the comment refers to the desire to not call
qcom_slim_ngd_exit_dma() while we have an ongoing DMA TX transaction.
But any such transaction is initiated and completed within a single
qcom_slim_ngd_xfer_msg().
Prior to calling qcom_slim_ngd_exit_dma() the slim_controller is torn
down, all child devices are notified that the slimbus is gone and the
child devices are removed.
Stop taking the tx_lock in qcom_slim_ngd_ssr_pdr_notify() to avoid the
deadlock.
In the Linux kernel, the following vulnerability has been resolved:
agp/amd64: Fix broken error propagation in agp_amd64_probe()
A NULL pointer dereference was observed in the AMD64 AGP driver when
running in a virtualized environment (e.g. qemu/kvm) without a physical
AMD northbridge. The crash occurs in amd64_fetch_size() when attempting
to dereference the pointer returned by node_to_amd_nb(0).
The root cause of this crash is broken error propagation in
agp_amd64_probe(): When no AMD northbridges are found, cache_nbs()
correctly returns -ENODEV. However, the probe function erroneously
checks the return value against exactly -1, rather than < 0.
As a result, the hardware absence error is masked, allowing the driver
to improperly proceed with initialization. It eventually calls
agp_add_bridge(), which invokes amd64_fetch_size(). Since the hardware
does not exist, node_to_amd_nb(0) returns NULL, leading to a General
Protection Fault (GPF) when accessing its ->misc member.
Fix the issue by correcting the error check in agp_amd64_probe() to
abort properly when cache_nbs() returns any negative error code. This
prevents the driver from erroneously proceeding without hardware, thereby
avoiding the subsequent NULL pointer dereference at its source.
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7921: Place upper limit on station AID
Any station configured with an AID over 20 causes a firmware crash.
This situation occurred in our testing using an AP interface on 7922
hardware, with a modified hostapd, sourced from Mediatek's OpenWRT
feeds.
In stock hostapd, station AIDs begin counting at 1, and this
configuration is prevented with an upper limit on associated stations.
However, the modified hostapd began allocation at 65, which caused the
firmware to crash. This fix does not allow these AIDs to work, but will
prevent the firmware crash.
This crash was only seen on IFTYPE_AP interfaces, and the fix does not
appear to have an effect on IFTYPE_STATION behavior.
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: reject zero bd_oblocknr in nilfs_ioctl_mark_blocks_dirty()
nilfs_ioctl_mark_blocks_dirty() uses bd_oblocknr to detect dead blocks
by comparing it with the current block number bd_blocknr. If they differ,
the block is considered dead and skipped.
However, bd_oblocknr should never be 0 since block 0 typically stores the
primary superblock and is never a valid GC target block. A corrupted ioctl
request with bd_oblocknr set to 0 causes the comparison to incorrectly
match when the lookup returns -ENOENT and sets bd_blocknr to 0, bypassing
the dead block check and calling nilfs_bmap_mark() on a non-existent
block. This causes nilfs_btree_do_lookup() to return -ENOENT, triggering
the WARN_ON(ret == -ENOENT).
Fix this by rejecting ioctl requests with bd_oblocknr set to 0 at the
beginning of each iteration.
[ryusuke: slightly modified the commit message and comments for accuracy]
In the Linux kernel, the following vulnerability has been resolved:
ocfs2/dlm: fix off-by-one in dlm_match_regions() region comparison
The local-vs-remote region comparison loop uses '<=' instead of '<',
causing it to read one entry past the valid range of qr_regions. The
other loops in the same function correctly use '<'.
Fix the loop condition to use '<' for consistency and correctness.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Avoid NULL dereference in dc_dmub_srv error paths
In dc_dmub_srv_log_diagnostic_data() and
dc_dmub_srv_enable_dpia_trace().
Both functions check:
if (!dc_dmub_srv || !dc_dmub_srv->dmub)
and then call DC_LOG_ERROR() inside that block.
DC_LOG_ERROR() uses dc_dmub_srv->ctx internally. So if
dc_dmub_srv is NULL, the logging itself can dereference a
NULL pointer and cause a crash.
Fix this by splitting the checks.
First check if dc_dmub_srv is NULL and return immediately.
Then check dc_dmub_srv->dmub and log the error only when
dc_dmub_srv is valid.
Fixes the below:
../display/dc/dc_dmub_srv.c:962 dc_dmub_srv_log_diagnostic_data() error: we previously assumed 'dc_dmub_srv' could be null (see line 961)
../display/dc/dc_dmub_srv.c:1167 dc_dmub_srv_enable_dpia_trace() error: we previously assumed 'dc_dmub_srv' could be null (see line 1166)