In the Linux kernel, the following vulnerability has been resolved:
cpufreq: amd-pstate: add check for cpufreq_cpu_get's return value
cpufreq_cpu_get may return NULL. To avoid NULL-dereference check it
and return in case of error.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
exec: don't WARN for racy path_noexec check
Both i_mode and noexec checks wrapped in WARN_ON stem from an artifact
of the previous implementation. They used to legitimately check for the
condition, but that got moved up in two commits:
633fb6ac3980 ("exec: move S_ISREG() check earlier")
0fd338b2d2cd ("exec: move path_noexec() check earlier")
Instead of being removed said checks are WARN_ON'ed instead, which
has some debug value.
However, the spurious path_noexec check is racy, resulting in
unwarranted warnings should someone race with setting the noexec flag.
One can note there is more to perm-checking whether execve is allowed
and none of the conditions are guaranteed to still hold after they were
tested for.
Additionally this does not validate whether the code path did any perm
checking to begin with -- it will pass if the inode happens to be
regular.
Keep the redundant path_noexec() check even though it's mindless
nonsense checking for guarantee that isn't given so drop the WARN.
Reword the commentary and do small tidy ups while here.
[brauner: keep redundant path_noexec() check]
In the Linux kernel, the following vulnerability has been resolved:
cpufreq: Avoid a bad reference count on CPU node
In the parse_perf_domain function, if the call to
of_parse_phandle_with_args returns an error, then the reference to the
CPU device node that was acquired at the start of the function would not
be properly decremented.
Address this by declaring the variable with the __free(device_node)
cleanup attribute.
In the Linux kernel, the following vulnerability has been resolved:
exfat: fix memory leak in exfat_load_bitmap()
If the first directory entry in the root directory is not a bitmap
directory entry, 'bh' will not be released and reassigned, which
will cause a memory leak.
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix access to uninitialised lock in fc replay path
The following kernel trace can be triggered with fstest generic/629 when
executed against a filesystem with fast-commit feature enabled:
INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 0 PID: 866 Comm: mount Not tainted 6.10.0+ #11
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x66/0x90
register_lock_class+0x759/0x7d0
__lock_acquire+0x85/0x2630
? __find_get_block+0xb4/0x380
lock_acquire+0xd1/0x2d0
? __ext4_journal_get_write_access+0xd5/0x160
_raw_spin_lock+0x33/0x40
? __ext4_journal_get_write_access+0xd5/0x160
__ext4_journal_get_write_access+0xd5/0x160
ext4_reserve_inode_write+0x61/0xb0
__ext4_mark_inode_dirty+0x79/0x270
? ext4_ext_replay_set_iblocks+0x2f8/0x450
ext4_ext_replay_set_iblocks+0x330/0x450
ext4_fc_replay+0x14c8/0x1540
? jread+0x88/0x2e0
? rcu_is_watching+0x11/0x40
do_one_pass+0x447/0xd00
jbd2_journal_recover+0x139/0x1b0
jbd2_journal_load+0x96/0x390
ext4_load_and_init_journal+0x253/0xd40
ext4_fill_super+0x2cc6/0x3180
...
In the replay path there's an attempt to lock sbi->s_bdev_wb_lock in
function ext4_check_bdev_write_error(). Unfortunately, at this point this
spinlock has not been initialized yet. Moving it's initialization to an
earlier point in __ext4_fill_super() fixes this splat.
In the Linux kernel, the following vulnerability has been resolved:
ext4: dax: fix overflowing extents beyond inode size when partially writing
The dax_iomap_rw() does two things in each iteration: map written blocks
and copy user data to blocks. If the process is killed by user(See signal
handling in dax_iomap_iter()), the copied data will be returned and added
on inode size, which means that the length of written extents may exceed
the inode size, then fsck will fail. An example is given as:
dd if=/dev/urandom of=file bs=4M count=1
dax_iomap_rw
iomap_iter // round 1
ext4_iomap_begin
ext4_iomap_alloc // allocate 0~2M extents(written flag)
dax_iomap_iter // copy 2M data
iomap_iter // round 2
iomap_iter_advance
iter->pos += iter->processed // iter->pos = 2M
ext4_iomap_begin
ext4_iomap_alloc // allocate 2~4M extents(written flag)
dax_iomap_iter
fatal_signal_pending
done = iter->pos - iocb->ki_pos // done = 2M
ext4_handle_inode_extension
ext4_update_inode_size // inode size = 2M
fsck reports: Inode 13, i_size is 2097152, should be 4194304. Fix?
Fix the problem by truncating extents if the written length is smaller
than expected.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix NULL deref in mlx5e_tir_builder_alloc()
In mlx5e_tir_builder_alloc() kvzalloc() may return NULL
which is dereferenced on the next line in a reference
to the modify field.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Fix error path in multi-packet WQE transmit
Remove the erroneous unmap in case no DMA mapping was established
The multi-packet WQE transmit code attempts to obtain a DMA mapping for
the skb. This could fail, e.g. under memory pressure, when the IOMMU
driver just can't allocate more memory for page tables. While the code
tries to handle this in the path below the err_unmap label it erroneously
unmaps one entry from the sq's FIFO list of active mappings. Since the
current map attempt failed this unmap is removing some random DMA mapping
that might still be required. If the PCI function now presents that IOVA,
the IOMMU may assumes a rogue DMA access and e.g. on s390 puts the PCI
function in error state.
The erroneous behavior was seen in a stress-test environment that created
memory pressure.
In the Linux kernel, the following vulnerability has been resolved:
static_call: Handle module init failure correctly in static_call_del_module()
Module insertion invokes static_call_add_module() to initialize the static
calls in a module. static_call_add_module() invokes __static_call_init(),
which allocates a struct static_call_mod to either encapsulate the built-in
static call sites of the associated key into it so further modules can be
added or to append the module to the module chain.
If that allocation fails the function returns with an error code and the
module core invokes static_call_del_module() to clean up eventually added
static_call_mod entries.
This works correctly, when all keys used by the module were converted over
to a module chain before the failure. If not then static_call_del_module()
causes a #GP as it blindly assumes that key::mods points to a valid struct
static_call_mod.
The problem is that key::mods is not a individual struct member of struct
static_call_key, it's part of a union to save space:
union {
/* bit 0: 0 = mods, 1 = sites */
unsigned long type;
struct static_call_mod *mods;
struct static_call_site *sites;
};
key::sites is a pointer to the list of built-in usage sites of the static
call. The type of the pointer is differentiated by bit 0. A mods pointer
has the bit clear, the sites pointer has the bit set.
As static_call_del_module() blidly assumes that the pointer is a valid
static_call_mod type, it fails to check for this failure case and
dereferences the pointer to the list of built-in call sites, which is
obviously bogus.
Cure it by checking whether the key has a sites or a mods pointer.
If it's a sites pointer then the key is not to be touched. As the sites are
walked in the same order as in __static_call_init() the site walk can be
terminated because all subsequent sites have not been touched by the init
code due to the error exit.
If it was converted before the allocation fail, then the inner loop which
searches for a module match will find nothing.
A fail in the second allocation in __static_call_init() is harmless and
does not require special treatment. The first allocation succeeded and
converted the key to a module chain. That first entry has mod::mod == NULL
and mod::next == NULL, so the inner loop of static_call_del_module() will
neither find a module match nor a module chain. The next site in the walk
was either already converted, but can't match the module, or it will exit
the outer loop because it has a static_call_site pointer and not a
static_call_mod pointer.
In the Linux kernel, the following vulnerability has been resolved:
platform/x86: x86-android-tablets: Fix use after free on platform_device_register() errors
x86_android_tablet_remove() frees the pdevs[] array, so it should not
be used after calling x86_android_tablet_remove().
When platform_device_register() fails, store the pdevs[x] PTR_ERR() value
into the local ret variable before calling x86_android_tablet_remove()
to avoid using pdevs[] after it has been freed.