In the Linux kernel, the following vulnerability has been resolved:
iio: light: veml6030: fix IIO device retrieval from embedded device
The dev pointer that is received as an argument in the
in_illuminance_period_available_show function references the device
embedded in the IIO device, not in the i2c client.
dev_to_iio_dev() must be used to accessthe right data. The current
implementation leads to a segmentation fault on every attempt to read
the attribute because indio_dev gets a NULL assignment.
This bug has been present since the first appearance of the driver,
apparently since the last version (V6) before getting applied. A
constant attribute was used until then, and the last modifications might
have not been tested again.
In the Linux kernel, the following vulnerability has been resolved:
mm/swapfile: skip HugeTLB pages for unuse_vma
I got a bad pud error and lost a 1GB HugeTLB when calling swapoff. The
problem can be reproduced by the following steps:
1. Allocate an anonymous 1GB HugeTLB and some other anonymous memory.
2. Swapout the above anonymous memory.
3. run swapoff and we will get a bad pud error in kernel message:
mm/pgtable-generic.c:42: bad pud 00000000743d215d(84000001400000e7)
We can tell that pud_clear_bad is called by pud_none_or_clear_bad in
unuse_pud_range() by ftrace. And therefore the HugeTLB pages will never
be freed because we lost it from page table. We can skip HugeTLB pages
for unuse_vma to fix it.
In the Linux kernel, the following vulnerability has been resolved:
maple_tree: correct tree corruption on spanning store
Patch series "maple_tree: correct tree corruption on spanning store", v3.
There has been a nasty yet subtle maple tree corruption bug that appears
to have been in existence since the inception of the algorithm.
This bug seems far more likely to happen since commit f8d112a4e657
("mm/mmap: avoid zeroing vma tree in mmap_region()"), which is the point
at which reports started to be submitted concerning this bug.
We were made definitely aware of the bug thanks to the kind efforts of
Bert Karwatzki who helped enormously in my being able to track this down
and identify the cause of it.
The bug arises when an attempt is made to perform a spanning store across
two leaf nodes, where the right leaf node is the rightmost child of the
shared parent, AND the store completely consumes the right-mode node.
This results in mas_wr_spanning_store() mitakenly duplicating the new and
existing entries at the maximum pivot within the range, and thus maple
tree corruption.
The fix patch corrects this by detecting this scenario and disallowing the
mistaken duplicate copy.
The fix patch commit message goes into great detail as to how this occurs.
This series also includes a test which reliably reproduces the issue, and
asserts that the fix works correctly.
Bert has kindly tested the fix and confirmed it resolved his issues. Also
Mikhail Gavrilov kindly reported what appears to be precisely the same
bug, which this fix should also resolve.
This patch (of 2):
There has been a subtle bug present in the maple tree implementation from
its inception.
This arises from how stores are performed - when a store occurs, it will
overwrite overlapping ranges and adjust the tree as necessary to
accommodate this.
A range may always ultimately span two leaf nodes. In this instance we
walk the two leaf nodes, determine which elements are not overwritten to
the left and to the right of the start and end of the ranges respectively
and then rebalance the tree to contain these entries and the newly
inserted one.
This kind of store is dubbed a 'spanning store' and is implemented by
mas_wr_spanning_store().
In order to reach this stage, mas_store_gfp() invokes
mas_wr_preallocate(), mas_wr_store_type() and mas_wr_walk() in turn to
walk the tree and update the object (mas) to traverse to the location
where the write should be performed, determining its store type.
When a spanning store is required, this function returns false stopping at
the parent node which contains the target range, and mas_wr_store_type()
marks the mas->store_type as wr_spanning_store to denote this fact.
When we go to perform the store in mas_wr_spanning_store(), we first
determine the elements AFTER the END of the range we wish to store (that
is, to the right of the entry to be inserted) - we do this by walking to
the NEXT pivot in the tree (i.e. r_mas.last + 1), starting at the node we
have just determined contains the range over which we intend to write.
We then turn our attention to the entries to the left of the entry we are
inserting, whose state is represented by l_mas, and copy these into a 'big
node', which is a special node which contains enough slots to contain two
leaf node's worth of data.
We then copy the entry we wish to store immediately after this - the copy
and the insertion of the new entry is performed by mas_store_b_node().
After this we copy the elements to the right of the end of the range which
we are inserting, if we have not exceeded the length of the node (i.e.
r_mas.offset <= r_mas.end).
Herein lies the bug - under very specific circumstances, this logic can
break and corrupt the maple tree.
Consider the following tree:
Height
0 Root Node
/ \
pivot = 0xffff / \ pivot = ULONG_MAX
/
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
drm/radeon: Fix encoder->possible_clones
Include the encoder itself in its possible_clones bitmask.
In the past nothing validated that drivers were populating
possible_clones correctly, but that changed in commit
74d2aacbe840 ("drm: Validate encoder->possible_clones").
Looks like radeon never got the memo and is still not
following the rules 100% correctly.
This results in some warnings during driver initialization:
Bogus possible_clones: [ENCODER:46:TV-46] possible_clones=0x4 (full encoder mask=0x7)
WARNING: CPU: 0 PID: 170 at drivers/gpu/drm/drm_mode_config.c:615 drm_mode_config_validate+0x113/0x39c
...
(cherry picked from commit 3b6e7d40649c0d75572039aff9d0911864c689db)
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: propagate directory read errors from nilfs_find_entry()
Syzbot reported that a task hang occurs in vcs_open() during a fuzzing
test for nilfs2.
The root cause of this problem is that in nilfs_find_entry(), which
searches for directory entries, ignores errors when loading a directory
page/folio via nilfs_get_folio() fails.
If the filesystem images is corrupted, and the i_size of the directory
inode is large, and the directory page/folio is successfully read but
fails the sanity check, for example when it is zero-filled,
nilfs_check_folio() may continue to spit out error messages in bursts.
Fix this issue by propagating the error to the callers when loading a
page/folio fails in nilfs_find_entry().
The current interface of nilfs_find_entry() and its callers is outdated
and cannot propagate error codes such as -EIO and -ENOMEM returned via
nilfs_find_entry(), so fix it together.
In the Linux kernel, the following vulnerability has been resolved:
ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size()
The step variable is initialized to zero. It is changed in the loop,
but if it's not changed it will remain zero. Add a variable check
before the division.
The observed behavior was introduced by commit 826b5de90c0b
("ALSA: firewire-lib: fix insufficient PCM rule for period/buffer size"),
and it is difficult to show that any of the interval parameters will
satisfy the snd_interval_test() condition with data from the
amdtp_rate_table[] table.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
cpufreq: loongson3: Use raw_smp_processor_id() in do_service_request()
Use raw_smp_processor_id() instead of plain smp_processor_id() in
do_service_request(), otherwise we may get some errors with the driver
enabled:
BUG: using smp_processor_id() in preemptible [00000000] code: (udev-worker)/208
caller is loongson3_cpufreq_probe+0x5c/0x250 [loongson3_cpufreq]
In the Linux kernel, the following vulnerability has been resolved:
ceph: remove the incorrect Fw reference check when dirtying pages
When doing the direct-io reads it will also try to mark pages dirty,
but for the read path it won't hold the Fw caps and there is case
will it get the Fw reference.
In the Linux kernel, the following vulnerability has been resolved:
fbdev: sisfb: Fix strbuf array overflow
The values of the variables xres and yres are placed in strbuf.
These variables are obtained from strbuf1.
The strbuf1 array contains digit characters
and a space if the array contains non-digit characters.
Then, when executing sprintf(strbuf, "%ux%ux8", xres, yres);
more than 16 bytes will be written to strbuf.
It is suggested to increase the size of the strbuf array to 24.
Found by Linux Verification Center (linuxtesting.org) with SVACE.