In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix potential kernel bug due to lack of writeback flag waiting
Destructive writes to a block device on which nilfs2 is mounted can cause
a kernel bug in the folio/page writeback start routine or writeback end
routine (__folio_start_writeback in the log below):
kernel BUG at mm/page-writeback.c:3070!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
...
RIP: 0010:__folio_start_writeback+0xbaa/0x10e0
Code: 25 ff 0f 00 00 0f 84 18 01 00 00 e8 40 ca c6 ff e9 17 f6 ff ff
e8 36 ca c6 ff 4c 89 f7 48 c7 c6 80 c0 12 84 e8 e7 b3 0f 00 90 <0f>
0b e8 1f ca c6 ff 4c 89 f7 48 c7 c6 a0 c6 12 84 e8 d0 b3 0f 00
...
Call Trace:
<TASK>
nilfs_segctor_do_construct+0x4654/0x69d0 [nilfs2]
nilfs_segctor_construct+0x181/0x6b0 [nilfs2]
nilfs_segctor_thread+0x548/0x11c0 [nilfs2]
kthread+0x2f0/0x390
ret_from_fork+0x4b/0x80
ret_from_fork_asm+0x1a/0x30
</TASK>
This is because when the log writer starts a writeback for segment summary
blocks or a super root block that use the backing device's page cache, it
does not wait for the ongoing folio/page writeback, resulting in an
inconsistent writeback state.
Fix this issue by waiting for ongoing writebacks when putting
folios/pages on the backing device into writeback state.
In the Linux kernel, the following vulnerability has been resolved:
media: lgdt3306a: Add a check against null-pointer-def
The driver should check whether the client provides the platform_data.
The following log reveals it:
[ 29.610324] BUG: KASAN: null-ptr-deref in kmemdup+0x30/0x40
[ 29.610730] Read of size 40 at addr 0000000000000000 by task bash/414
[ 29.612820] Call Trace:
[ 29.613030] <TASK>
[ 29.613201] dump_stack_lvl+0x56/0x6f
[ 29.613496] ? kmemdup+0x30/0x40
[ 29.613754] print_report.cold+0x494/0x6b7
[ 29.614082] ? kmemdup+0x30/0x40
[ 29.614340] kasan_report+0x8a/0x190
[ 29.614628] ? kmemdup+0x30/0x40
[ 29.614888] kasan_check_range+0x14d/0x1d0
[ 29.615213] memcpy+0x20/0x60
[ 29.615454] kmemdup+0x30/0x40
[ 29.615700] lgdt3306a_probe+0x52/0x310
[ 29.616339] i2c_device_probe+0x951/0xa90
In the Linux kernel, the following vulnerability has been resolved:
tracing/probes: fix error check in parse_btf_field()
btf_find_struct_member() might return NULL or an error via the
ERR_PTR() macro. However, its caller in parse_btf_field() only checks
for the NULL condition. Fix this by using IS_ERR() and returning the
error up the stack.
In the Linux kernel, the following vulnerability has been resolved:
dma-buf/sw-sync: don't enable IRQ from sync_print_obj()
Since commit a6aa8fca4d79 ("dma-buf/sw-sync: Reduce irqsave/irqrestore from
known context") by error replaced spin_unlock_irqrestore() with
spin_unlock_irq() for both sync_debugfs_show() and sync_print_obj() despite
sync_print_obj() is called from sync_debugfs_show(), lockdep complains
inconsistent lock state warning.
Use plain spin_{lock,unlock}() for sync_print_obj(), for
sync_debugfs_show() is already using spin_{lock,unlock}_irq().
In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: Fix loop termination condition in gss_free_in_token_pages()
The in_token->pages[] array is not NULL terminated. This results in
the following KASAN splat:
KASAN: maybe wild-memory-access in range [0x04a2013400000008-0x04a201340000000f]
In the Linux kernel, the following vulnerability has been resolved:
serial: max3100: Update uart_driver_registered on driver removal
The removal of the last MAX3100 device triggers the removal of
the driver. However, code doesn't update the respective global
variable and after insmod — rmmod — insmod cycle the kernel
oopses:
max3100 spi-PRP0001:01: max3100_probe: adding port 0
BUG: kernel NULL pointer dereference, address: 0000000000000408
...
RIP: 0010:serial_core_register_port+0xa0/0x840
...
max3100_probe+0x1b6/0x280 [max3100]
spi_probe+0x8d/0xb0
Update the actual state so next time UART driver will be registered
again.
Hugo also noticed, that the error path in the probe also affected
by having the variable set, and not cleared. Instead of clearing it
move the assignment after the successfull uart_register_driver() call.
In the Linux kernel, the following vulnerability has been resolved:
serial: max3100: Lock port->lock when calling uart_handle_cts_change()
uart_handle_cts_change() has to be called with port lock taken,
Since we run it in a separate work, the lock may not be taken at
the time of running. Make sure that it's taken by explicitly doing
that. Without it we got a splat:
WARNING: CPU: 0 PID: 10 at drivers/tty/serial/serial_core.c:3491 uart_handle_cts_change+0xa6/0xb0
...
Workqueue: max3100-0 max3100_work [max3100]
RIP: 0010:uart_handle_cts_change+0xa6/0xb0
...
max3100_handlerx+0xc5/0x110 [max3100]
max3100_work+0x12a/0x340 [max3100]
In the Linux kernel, the following vulnerability has been resolved:
soundwire: cadence: fix invalid PDI offset
For some reason, we add an offset to the PDI, presumably to skip the
PDI0 and PDI1 which are reserved for BPT.
This code is however completely wrong and leads to an out-of-bounds
access. We were just lucky so far since we used only a couple of PDIs
and remained within the PDI array bounds.
A Fixes: tag is not provided since there are no known platforms where
the out-of-bounds would be accessed, and the initial code had problems
as well.
A follow-up patch completely removes this useless offset.
In the Linux kernel, the following vulnerability has been resolved:
enic: Validate length of nl attributes in enic_set_vf_port
enic_set_vf_port assumes that the nl attribute IFLA_PORT_PROFILE
is of length PORT_PROFILE_MAX and that the nl attributes
IFLA_PORT_INSTANCE_UUID, IFLA_PORT_HOST_UUID are of length PORT_UUID_MAX.
These attributes are validated (in the function do_setlink in rtnetlink.c)
using the nla_policy ifla_port_policy. The policy defines IFLA_PORT_PROFILE
as NLA_STRING, IFLA_PORT_INSTANCE_UUID as NLA_BINARY and
IFLA_PORT_HOST_UUID as NLA_STRING. That means that the length validation
using the policy is for the max size of the attributes and not on exact
size so the length of these attributes might be less than the sizes that
enic_set_vf_port expects. This might cause an out of bands
read access in the memcpys of the data of these
attributes in enic_set_vf_port.
In the Linux kernel, the following vulnerability has been resolved:
media: stk1160: fix bounds checking in stk1160_copy_video()
The subtract in this condition is reversed. The ->length is the length
of the buffer. The ->bytesused is how many bytes we have copied thus
far. When the condition is reversed that means the result of the
subtraction is always negative but since it's unsigned then the result
is a very high positive value. That means the overflow check is never
true.
Additionally, the ->bytesused doesn't actually work for this purpose
because we're not writing to "buf->mem + buf->bytesused". Instead, the
math to calculate the destination where we are writing is a bit
involved. You calculate the number of full lines already written,
multiply by two, skip a line if necessary so that we start on an odd
numbered line, and add the offset into the line.
To fix this buffer overflow, just take the actual destination where we
are writing, if the offset is already out of bounds print an error and
return. Otherwise, write up to buf->length bytes.