In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check link_res->hpo_dp_link_enc before using it
[WHAT & HOW]
Functions dp_enable_link_phy and dp_disable_link_phy can pass link_res
without initializing hpo_dp_link_enc and it is necessary to check for
null before dereferencing.
This fixes 2 FORWARD_NULL issues reported by Coverity.
In the Linux kernel, the following vulnerability has been resolved:
mm: avoid leaving partial pfn mappings around in error case
As Jann points out, PFN mappings are special, because unlike normal
memory mappings, there is no lifetime information associated with the
mapping - it is just a raw mapping of PFNs with no reference counting of
a 'struct page'.
That's all very much intentional, but it does mean that it's easy to
mess up the cleanup in case of errors. Yes, a failed mmap() will always
eventually clean up any partial mappings, but without any explicit
lifetime in the page table mapping itself, it's very easy to do the
error handling in the wrong order.
In particular, it's easy to mistakenly free the physical backing store
before the page tables are actually cleaned up and (temporarily) have
stale dangling PTE entries.
To make this situation less error-prone, just make sure that any partial
pfn mapping is torn down early, before any other error handling.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Avoid overflow from uint32_t to uint8_t
[WHAT & HOW]
dmub_rb_cmd's ramping_boundary has size of uint8_t and it is assigned
0xFFFF. Fix it by changing it to uint8_t with value of 0xFF.
This fixes 2 INTEGER_OVERFLOW issues reported by Coverity.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Remove register from DCN35 DMCUB diagnostic collection
[Why]
These registers should not be read from driver and triggering the
security violation when DMCUB work times out and diagnostics are
collected blocks Z8 entry.
[How]
Remove the register read from DCN35.
In the Linux kernel, the following vulnerability has been resolved:
spi: hisi-kunpeng: Add verification for the max_frequency provided by the firmware
If the value of max_speed_hz is 0, it may cause a division by zero
error in hisi_calc_effective_speed().
The value of max_speed_hz is provided by firmware.
Firmware is generally considered as a trusted domain. However, as
division by zero errors can cause system failure, for defense measure,
the value of max_speed is validated here. So 0 is regarded as invalid
and an error code is returned.
In the Linux kernel, the following vulnerability has been resolved:
i3c: mipi-i3c-hci: Error out instead on BUG_ON() in IBI DMA setup
Definitely condition dma_get_cache_alignment * defined value > 256
during driver initialization is not reason to BUG_ON(). Turn that to
graceful error out with -EINVAL.
In the Linux kernel, the following vulnerability has been resolved:
scsi: pm80xx: Set phy->enable_completion only when we wait for it
pm8001_phy_control() populates the enable_completion pointer with a stack
address, sends a PHY_LINK_RESET / PHY_HARD_RESET, waits 300 ms, and
returns. The problem arises when a phy control response comes late. After
300 ms the pm8001_phy_control() function returns and the passed
enable_completion stack address is no longer valid. Late phy control
response invokes complete() on a dangling enable_completion pointer which
leads to a kernel crash.
In the Linux kernel, the following vulnerability has been resolved:
PCI: keystone: Add workaround for Errata #i2037 (AM65x SR 1.0)
Errata #i2037 in AM65x/DRA80xM Processors Silicon Revision 1.0
(SPRZ452D_July 2018_Revised December 2019 [1]) mentions when an
inbound PCIe TLP spans more than two internal AXI 128-byte bursts,
the bus may corrupt the packet payload and the corrupt data may
cause associated applications or the processor to hang.
The workaround for Errata #i2037 is to limit the maximum read
request size and maximum payload size to 128 bytes. Add workaround
for Errata #i2037 here.
The errata and workaround is applicable only to AM65x SR 1.0 and
later versions of the silicon will have this fixed.
[1] -> https://www.ti.com/lit/er/sprz452i/sprz452i.pdf
In the Linux kernel, the following vulnerability has been resolved:
lib/generic-radix-tree.c: Fix rare race in __genradix_ptr_alloc()
If we need to increase the tree depth, allocate a new node, and then
race with another thread that increased the tree depth before us, we'll
still have a preallocated node that might be used later.
If we then use that node for a new non-root node, it'll still have a
pointer to the old root instead of being zeroed - fix this by zeroing it
in the cmpxchg failure path.