Linux: >> Linux Kernel >> 4.19.115 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
xenbus: Use kref to track req lifetime
Marek reported seeing a NULL pointer fault in the xenbus_thread
callstack:
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: e030:__wake_up_common+0x4c/0x180
Call Trace:
<TASK>
__wake_up_common_lock+0x82/0xd0
process_msg+0x18e/0x2f0
xenbus_thread+0x165/0x1c0
process_msg+0x18e is req->cb(req). req->cb is set to xs_wake_up(), a
thin wrapper around wake_up(), or xenbus_dev_queue_reply(). It seems
like it was xs_wake_up() in this case.
It seems like req may have woken up the xs_wait_for_reply(), which
kfree()ed the req. When xenbus_thread resumes, it faults on the zero-ed
data.
Linux Device Drivers 2nd edition states:
"Normally, a wake_up call can cause an immediate reschedule to happen,
meaning that other processes might run before wake_up returns."
... which would match the behaviour observed.
Change to keeping two krefs on each request. One for the caller, and
one for xenbus_thread. Each will kref_put() when finished, and the last
will free it.
This use of kref matches the description in
Documentation/core-api/kref.rst
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
ftrace: Add cond_resched() to ftrace_graph_set_hash()
When the kernel contains a large number of functions that can be traced,
the loop in ftrace_graph_set_hash() may take a lot of time to execute.
This may trigger the softlockup watchdog.
Add cond_resched() within the loop to allow the kernel to remain
responsive even when processing a large number of functions.
This matches the cond_resched() that is used in other locations of the
code that iterates over all functions that can be traced.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
objtool, media: dib8000: Prevent divide-by-zero in dib8000_set_dds()
If dib8000_set_dds()'s call to dib8000_read32() returns zero, the result
is a divide-by-zero. Prevent that from happening.
Fixes the following warning with an UBSAN kernel:
drivers/media/dvb-frontends/dib8000.o: warning: objtool: dib8000_tune() falls through to next function dib8096p_cfg_DibRx()
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
iommu/amd: Fix potential buffer overflow in parse_ivrs_acpihid
There is a string parsing logic error which can lead to an overflow of hid
or uid buffers. Comparing ACPIID_LEN against a total string length doesn't
take into account the lengths of individual hid and uid buffers so the
check is insufficient in some cases. For example if the length of hid
string is 4 and the length of the uid string is 260, the length of str
will be equal to ACPIID_LEN + 1 but uid string will overflow uid buffer
which size is 256.
The same applies to the hid string with length 13 and uid string with
length 250.
Check the length of hid and uid strings separately to prevent
buffer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
dm-bufio: don't schedule in atomic context
A BUG was reported as below when CONFIG_DEBUG_ATOMIC_SLEEP and
try_verify_in_tasklet are enabled.
[ 129.444685][ T934] BUG: sleeping function called from invalid context at drivers/md/dm-bufio.c:2421
[ 129.444723][ T934] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 934, name: kworker/1:4
[ 129.444740][ T934] preempt_count: 201, expected: 0
[ 129.444756][ T934] RCU nest depth: 0, expected: 0
[ 129.444781][ T934] Preemption disabled at:
[ 129.444789][ T934] [<ffffffd816231900>] shrink_work+0x21c/0x248
[ 129.445167][ T934] kernel BUG at kernel/sched/walt/walt_debug.c:16!
[ 129.445183][ T934] Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
[ 129.445204][ T934] Skip md ftrace buffer dump for: 0x1609e0
[ 129.447348][ T934] CPU: 1 PID: 934 Comm: kworker/1:4 Tainted: G W OE 6.6.56-android15-8-o-g6f82312b30b9-debug #1 1400000003000000474e5500b3187743670464e8
[ 129.447362][ T934] Hardware name: Qualcomm Technologies, Inc. Parrot QRD, Alpha-M (DT)
[ 129.447373][ T934] Workqueue: dm_bufio_cache shrink_work
[ 129.447394][ T934] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 129.447406][ T934] pc : android_rvh_schedule_bug+0x0/0x8 [sched_walt_debug]
[ 129.447435][ T934] lr : __traceiter_android_rvh_schedule_bug+0x44/0x6c
[ 129.447451][ T934] sp : ffffffc0843dbc90
[ 129.447459][ T934] x29: ffffffc0843dbc90 x28: ffffffffffffffff x27: 0000000000000c8b
[ 129.447479][ T934] x26: 0000000000000040 x25: ffffff804b3d6260 x24: ffffffd816232b68
[ 129.447497][ T934] x23: ffffff805171c5b4 x22: 0000000000000000 x21: ffffffd816231900
[ 129.447517][ T934] x20: ffffff80306ba898 x19: 0000000000000000 x18: ffffffc084159030
[ 129.447535][ T934] x17: 00000000d2b5dd1f x16: 00000000d2b5dd1f x15: ffffffd816720358
[ 129.447554][ T934] x14: 0000000000000004 x13: ffffff89ef978000 x12: 0000000000000003
[ 129.447572][ T934] x11: ffffffd817a823c4 x10: 0000000000000202 x9 : 7e779c5735de9400
[ 129.447591][ T934] x8 : ffffffd81560d004 x7 : 205b5d3938373434 x6 : ffffffd8167397c8
[ 129.447610][ T934] x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffffffc0843db9e0
[ 129.447629][ T934] x2 : 0000000000002f15 x1 : 0000000000000000 x0 : 0000000000000000
[ 129.447647][ T934] Call trace:
[ 129.447655][ T934] android_rvh_schedule_bug+0x0/0x8 [sched_walt_debug 1400000003000000474e550080cce8a8a78606b6]
[ 129.447681][ T934] __might_resched+0x190/0x1a8
[ 129.447694][ T934] shrink_work+0x180/0x248
[ 129.447706][ T934] process_one_work+0x260/0x624
[ 129.447718][ T934] worker_thread+0x28c/0x454
[ 129.447729][ T934] kthread+0x118/0x158
[ 129.447742][ T934] ret_from_fork+0x10/0x20
[ 129.447761][ T934] Code: ???????? ???????? ???????? d2b5dd1f (d4210000)
[ 129.447772][ T934] ---[ end trace 0000000000000000 ]---
dm_bufio_lock will call spin_lock_bh when try_verify_in_tasklet
is enabled, and __scan will be called in atomic context.
CVSS Score
7.8
EPSS Score
0.003
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
sch_htb: make htb_qlen_notify() idempotent
htb_qlen_notify() always deactivates the HTB class and in fact could
trigger a warning if it is already deactivated. Therefore, it is not
idempotent and not friendly to its callers, like fq_codel_dequeue().
Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers'
life.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix oob write in trace_seq_to_buffer()
syzbot reported this bug:
==================================================================
BUG: KASAN: slab-out-of-bounds in trace_seq_to_buffer kernel/trace/trace.c:1830 [inline]
BUG: KASAN: slab-out-of-bounds in tracing_splice_read_pipe+0x6be/0xdd0 kernel/trace/trace.c:6822
Write of size 4507 at addr ffff888032b6b000 by task syz.2.320/7260
CPU: 1 UID: 0 PID: 7260 Comm: syz.2.320 Not tainted 6.15.0-rc1-syzkaller-00301-g3bde70a2c827 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc3/0x670 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
__asan_memcpy+0x3c/0x60 mm/kasan/shadow.c:106
trace_seq_to_buffer kernel/trace/trace.c:1830 [inline]
tracing_splice_read_pipe+0x6be/0xdd0 kernel/trace/trace.c:6822
....
==================================================================
It has been reported that trace_seq_to_buffer() tries to copy more data
than PAGE_SIZE to buf. Therefore, to prevent this, we should use the
smaller of trace_seq_used(&iter->seq) and PAGE_SIZE as an argument.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
net: lan743x: Fix memleak issue when GSO enabled
Always map the `skb` to the LS descriptor. Previously skb was
mapped to EXT descriptor when the number of fragments is zero with
GSO enabled. Mapping the skb to EXT descriptor prevents it from
being freed, leading to a memory leak
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
bnxt_en: Fix out-of-bound memcpy() during ethtool -w
When retrieving the FW coredump using ethtool, it can sometimes cause
memory corruption:
BUG: KFENCE: memory corruption in __bnxt_get_coredump+0x3ef/0x670 [bnxt_en]
Corrupted memory at 0x000000008f0f30e8 [ ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ] (in kfence-#45):
__bnxt_get_coredump+0x3ef/0x670 [bnxt_en]
ethtool_get_dump_data+0xdc/0x1a0
__dev_ethtool+0xa1e/0x1af0
dev_ethtool+0xa8/0x170
dev_ioctl+0x1b5/0x580
sock_do_ioctl+0xab/0xf0
sock_ioctl+0x1ce/0x2e0
__x64_sys_ioctl+0x87/0xc0
do_syscall_64+0x5c/0xf0
entry_SYSCALL_64_after_hwframe+0x78/0x80
...
This happens when copying the coredump segment list in
bnxt_hwrm_dbg_dma_data() with the HWRM_DBG_COREDUMP_LIST FW command.
The info->dest_buf buffer is allocated based on the number of coredump
segments returned by the FW. The segment list is then DMA'ed by
the FW and the length of the DMA is returned by FW. The driver then
copies this DMA'ed segment list to info->dest_buf.
In some cases, this DMA length may exceed the info->dest_buf length
and cause the above BUG condition. Fix it by capping the copy
length to not exceed the length of info->dest_buf. The extra
DMA data contains no useful information.
This code path is shared for the HWRM_DBG_COREDUMP_LIST and the
HWRM_DBG_COREDUMP_RETRIEVE FW commands. The buffering is different
for these 2 FW commands. To simplify the logic, we need to move
the line to adjust the buffer length for HWRM_DBG_COREDUMP_RETRIEVE
up, so that the new check to cap the copy length will work for both
commands.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-20
In the Linux kernel, the following vulnerability has been resolved:
mtd: inftlcore: Add error check for inftl_read_oob()
In INFTL_findwriteunit(), the return value of inftl_read_oob()
need to be checked. A proper implementation can be
found in INFTL_deleteblock(). The status will be set as
SECTOR_IGNORE to break from the while-loop correctly
if the inftl_read_oob() fails.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-20