Linux: >> Linux Kernel >> 2.0 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
hugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param()
Syzkaller reports a null-ptr-deref bug as follows:
======================================================
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380
[...]
Call Trace:
<TASK>
vfs_parse_fs_param fs/fs_context.c:148 [inline]
vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129
vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191
generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231
do_new_mount fs/namespace.c:3036 [inline]
path_mount+0x12de/0x1e20 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3568
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
[...]
</TASK>
======================================================
According to commit "vfs: parse: deal with zero length string value",
kernel will set the param->string to null pointer in vfs_parse_fs_string()
if fs string has zero length.
Yet the problem is that, hugetlbfs_parse_param() will dereference the
param->string, without checking whether it is a null pointer. To be more
specific, if hugetlbfs_parse_param() parses an illegal mount parameter,
such as "size=,", kernel will constructs struct fs_parameter with null
pointer in vfs_parse_fs_string(), then passes this struct fs_parameter to
hugetlbfs_parse_param(), which triggers the above null-ptr-deref bug.
This patch solves it by adding sanity check on param->string
in hugetlbfs_parse_param().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
jbd2: fix potential use-after-free in jbd2_fc_wait_bufs
In 'jbd2_fc_wait_bufs' use 'bh' after put buffer head reference count
which may lead to use-after-free.
So judge buffer if uptodate before put buffer head reference count.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
nbd: Fix hung when signal interrupts nbd_start_device_ioctl()
syzbot reported hung task [1]. The following program is a simplified
version of the reproducer:
int main(void)
{
int sv[2], fd;
if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv) < 0)
return 1;
if ((fd = open("/dev/nbd0", 0)) < 0)
return 1;
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, 0x81) < 0)
return 1;
if (ioctl(fd, NBD_SET_SOCK, sv[0]) < 0)
return 1;
if (ioctl(fd, NBD_DO_IT) < 0)
return 1;
return 0;
}
When signal interrupt nbd_start_device_ioctl() waiting the condition
atomic_read(&config->recv_threads) == 0, the task can hung because it
waits the completion of the inflight IOs.
This patch fixes the issue by clearing queue, not just shutdown, when
signal interrupt nbd_start_device_ioctl().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
ata: ahci: Match EM_MAX_SLOTS with SATA_PMP_MAX_PORTS
UBSAN complains about array-index-out-of-bounds:
[ 1.980703] kernel: UBSAN: array-index-out-of-bounds in /build/linux-9H675w/linux-5.15.0/drivers/ata/libahci.c:968:41
[ 1.980709] kernel: index 15 is out of range for type 'ahci_em_priv [8]'
[ 1.980713] kernel: CPU: 0 PID: 209 Comm: scsi_eh_8 Not tainted 5.15.0-25-generic #25-Ubuntu
[ 1.980716] kernel: Hardware name: System manufacturer System Product Name/P5Q3, BIOS 1102 06/11/2010
[ 1.980718] kernel: Call Trace:
[ 1.980721] kernel: <TASK>
[ 1.980723] kernel: show_stack+0x52/0x58
[ 1.980729] kernel: dump_stack_lvl+0x4a/0x5f
[ 1.980734] kernel: dump_stack+0x10/0x12
[ 1.980736] kernel: ubsan_epilogue+0x9/0x45
[ 1.980739] kernel: __ubsan_handle_out_of_bounds.cold+0x44/0x49
[ 1.980742] kernel: ahci_qc_issue+0x166/0x170 [libahci]
[ 1.980748] kernel: ata_qc_issue+0x135/0x240
[ 1.980752] kernel: ata_exec_internal_sg+0x2c4/0x580
[ 1.980754] kernel: ? vprintk_default+0x1d/0x20
[ 1.980759] kernel: ata_exec_internal+0x67/0xa0
[ 1.980762] kernel: sata_pmp_read+0x8d/0xc0
[ 1.980765] kernel: sata_pmp_read_gscr+0x3c/0x90
[ 1.980768] kernel: sata_pmp_attach+0x8b/0x310
[ 1.980771] kernel: ata_eh_revalidate_and_attach+0x28c/0x4b0
[ 1.980775] kernel: ata_eh_recover+0x6b6/0xb30
[ 1.980778] kernel: ? ahci_do_hardreset+0x180/0x180 [libahci]
[ 1.980783] kernel: ? ahci_stop_engine+0xb0/0xb0 [libahci]
[ 1.980787] kernel: ? ahci_do_softreset+0x290/0x290 [libahci]
[ 1.980792] kernel: ? trace_event_raw_event_ata_eh_link_autopsy_qc+0xe0/0xe0
[ 1.980795] kernel: sata_pmp_eh_recover.isra.0+0x214/0x560
[ 1.980799] kernel: sata_pmp_error_handler+0x23/0x40
[ 1.980802] kernel: ahci_error_handler+0x43/0x80 [libahci]
[ 1.980806] kernel: ata_scsi_port_error_handler+0x2b1/0x600
[ 1.980810] kernel: ata_scsi_error+0x9c/0xd0
[ 1.980813] kernel: scsi_error_handler+0xa1/0x180
[ 1.980817] kernel: ? scsi_unjam_host+0x1c0/0x1c0
[ 1.980820] kernel: kthread+0x12a/0x150
[ 1.980823] kernel: ? set_kthread_struct+0x50/0x50
[ 1.980826] kernel: ret_from_fork+0x22/0x30
[ 1.980831] kernel: </TASK>
This happens because sata_pmp_init_links() initialize link->pmp up to
SATA_PMP_MAX_PORTS while em_priv is declared as 8 elements array.
I can't find the maximum Enclosure Management ports specified in AHCI
spec v1.3.1, but "12.2.1 LED message type" states that "Port Multiplier
Information" can utilize 4 bits, which implies it can support up to 16
ports. Hence, use SATA_PMP_MAX_PORTS as EM_MAX_SLOTS to resolve the
issue.
BugLink: https://bugs.launchpad.net/bugs/1970074
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
ACPI: tables: FPDT: Don't call acpi_os_map_memory() on invalid phys address
On a Packard Bell Dot SC (Intel Atom N2600 model) there is a FPDT table
which contains invalid physical addresses, with high bits set which fall
outside the range of the CPU-s supported physical address range.
Calling acpi_os_map_memory() on such an invalid phys address leads to
the below WARN_ON in ioremap triggering resulting in an oops/stacktrace.
Add code to verify the physical address before calling acpi_os_map_memory()
to fix / avoid the oops.
[ 1.226900] ioremap: invalid physical address 3001000000000000
[ 1.226949] ------------[ cut here ]------------
[ 1.226962] WARNING: CPU: 1 PID: 1 at arch/x86/mm/ioremap.c:200 __ioremap_caller.cold+0x43/0x5f
[ 1.226996] Modules linked in:
[ 1.227016] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc3+ #490
[ 1.227029] Hardware name: Packard Bell dot s/SJE01_CT, BIOS V1.10 07/23/2013
[ 1.227038] RIP: 0010:__ioremap_caller.cold+0x43/0x5f
[ 1.227054] Code: 96 00 00 e9 f8 af 24 ff 89 c6 48 c7 c7 d8 0c 84 99 e8 6a 96 00 00 e9 76 af 24 ff 48 89 fe 48 c7 c7 a8 0c 84 99 e8 56 96 00 00 <0f> 0b e9 60 af 24 ff 48 8b 34 24 48 c7 c7 40 0d 84 99 e8 3f 96 00
[ 1.227067] RSP: 0000:ffffb18c40033d60 EFLAGS: 00010286
[ 1.227084] RAX: 0000000000000032 RBX: 3001000000000000 RCX: 0000000000000000
[ 1.227095] RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00000000ffffffff
[ 1.227105] RBP: 3001000000000000 R08: 0000000000000000 R09: ffffb18c40033c18
[ 1.227115] R10: 0000000000000003 R11: ffffffff99d62fe8 R12: 0000000000000008
[ 1.227124] R13: 0003001000000000 R14: 0000000000001000 R15: 3001000000000000
[ 1.227135] FS: 0000000000000000(0000) GS:ffff913a3c080000(0000) knlGS:0000000000000000
[ 1.227146] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.227156] CR2: 0000000000000000 CR3: 0000000018c26000 CR4: 00000000000006e0
[ 1.227167] Call Trace:
[ 1.227176] <TASK>
[ 1.227185] ? acpi_os_map_iomem+0x1c9/0x1e0
[ 1.227215] ? kmem_cache_alloc_trace+0x187/0x370
[ 1.227254] acpi_os_map_iomem+0x1c9/0x1e0
[ 1.227288] acpi_init_fpdt+0xa8/0x253
[ 1.227308] ? acpi_debugfs_init+0x1f/0x1f
[ 1.227339] do_one_initcall+0x5a/0x300
[ 1.227406] ? rcu_read_lock_sched_held+0x3f/0x80
[ 1.227442] kernel_init_freeable+0x28b/0x2cc
[ 1.227512] ? rest_init+0x170/0x170
[ 1.227538] kernel_init+0x16/0x140
[ 1.227552] ret_from_fork+0x1f/0x30
[ 1.227639] </TASK>
[ 1.227647] irq event stamp: 186819
[ 1.227656] hardirqs last enabled at (186825): [<ffffffff98184a6e>] __up_console_sem+0x5e/0x70
[ 1.227672] hardirqs last disabled at (186830): [<ffffffff98184a53>] __up_console_sem+0x43/0x70
[ 1.227686] softirqs last enabled at (186576): [<ffffffff980fbc9d>] __irq_exit_rcu+0xed/0x160
[ 1.227701] softirqs last disabled at (186569): [<ffffffff980fbc9d>] __irq_exit_rcu+0xed/0x160
[ 1.227715] ---[ end trace 0000000000000000 ]---
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix potential out of bound read in ext4_fc_replay_scan()
For scan loop must ensure that at least EXT4_FC_TAG_BASE_LEN space. If remain
space less than EXT4_FC_TAG_BASE_LEN which will lead to out of bound read
when mounting corrupt file system image.
ADD_RANGE/HEAD/TAIL is needed to add extra check when do journal scan, as this
three tags will read data during scan, tag length couldn't less than data length
which will read.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not BUG_ON() on ENOMEM when dropping extent items for a range
If we get -ENOMEM while dropping file extent items in a given range, at
btrfs_drop_extents(), due to failure to allocate memory when attempting to
increment the reference count for an extent or drop the reference count,
we handle it with a BUG_ON(). This is excessive, instead we can simply
abort the transaction and return the error to the caller. In fact most
callers of btrfs_drop_extents(), directly or indirectly, already abort
the transaction if btrfs_drop_extents() returns any error.
Also, we already have error paths at btrfs_drop_extents() that may return
-ENOMEM and in those cases we abort the transaction, like for example
anything that changes the b+tree may return -ENOMEM due to a failure to
allocate a new extent buffer when COWing an existing extent buffer, such
as a call to btrfs_duplicate_item() for example.
So replace the BUG_ON() calls with proper logic to abort the transaction
and return the error.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
UM: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK
When CONFIG_CPUMASK_OFFSTACK and CONFIG_DEBUG_PER_CPU_MAPS is selected,
cpu_max_bits_warn() generates a runtime warning similar as below while
we show /proc/cpuinfo. Fix this by using nr_cpu_ids (the runtime limit)
instead of NR_CPUS to iterate CPUs.
[ 3.052463] ------------[ cut here ]------------
[ 3.059679] WARNING: CPU: 3 PID: 1 at include/linux/cpumask.h:108 show_cpuinfo+0x5e8/0x5f0
[ 3.070072] Modules linked in: efivarfs autofs4
[ 3.076257] CPU: 0 PID: 1 Comm: systemd Not tainted 5.19-rc5+ #1052
[ 3.099465] Stack : 9000000100157b08 9000000000f18530 9000000000cf846c 9000000100154000
[ 3.109127] 9000000100157a50 0000000000000000 9000000100157a58 9000000000ef7430
[ 3.118774] 90000001001578e8 0000000000000040 0000000000000020 ffffffffffffffff
[ 3.128412] 0000000000aaaaaa 1ab25f00eec96a37 900000010021de80 900000000101c890
[ 3.138056] 0000000000000000 0000000000000000 0000000000000000 0000000000aaaaaa
[ 3.147711] ffff8000339dc220 0000000000000001 0000000006ab4000 0000000000000000
[ 3.157364] 900000000101c998 0000000000000004 9000000000ef7430 0000000000000000
[ 3.167012] 0000000000000009 000000000000006c 0000000000000000 0000000000000000
[ 3.176641] 9000000000d3de08 9000000001639390 90000000002086d8 00007ffff0080286
[ 3.186260] 00000000000000b0 0000000000000004 0000000000000000 0000000000071c1c
[ 3.195868] ...
[ 3.199917] Call Trace:
[ 3.203941] [<90000000002086d8>] show_stack+0x38/0x14c
[ 3.210666] [<9000000000cf846c>] dump_stack_lvl+0x60/0x88
[ 3.217625] [<900000000023d268>] __warn+0xd0/0x100
[ 3.223958] [<9000000000cf3c90>] warn_slowpath_fmt+0x7c/0xcc
[ 3.231150] [<9000000000210220>] show_cpuinfo+0x5e8/0x5f0
[ 3.238080] [<90000000004f578c>] seq_read_iter+0x354/0x4b4
[ 3.245098] [<90000000004c2e90>] new_sync_read+0x17c/0x1c4
[ 3.252114] [<90000000004c5174>] vfs_read+0x138/0x1d0
[ 3.258694] [<90000000004c55f8>] ksys_read+0x70/0x100
[ 3.265265] [<9000000000cfde9c>] do_syscall+0x7c/0x94
[ 3.271820] [<9000000000202fe4>] handle_syscall+0xc4/0x160
[ 3.281824] ---[ end trace 8b484262b4b8c24c ]---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix delayed allocation bug in ext4_clu_mapped for bigalloc + inline
When converting files with inline data to extents, delayed allocations
made on a file system created with both the bigalloc and inline options
can result in invalid extent status cache content, incorrect reserved
cluster counts, kernel memory leaks, and potential kernel panics.
With bigalloc, the code that determines whether a block must be
delayed allocated searches the extent tree to see if that block maps
to a previously allocated cluster. If not, the block is delayed
allocated, and otherwise, it isn't. However, if the inline option is
also used, and if the file containing the block is marked as able to
store data inline, there isn't a valid extent tree associated with
the file. The current code in ext4_clu_mapped() calls
ext4_find_extent() to search the non-existent tree for a previously
allocated cluster anyway, which typically finds nothing, as desired.
However, a side effect of the search can be to cache invalid content
from the non-existent tree (garbage) in the extent status tree,
including bogus entries in the pending reservation tree.
To fix this, avoid searching the extent tree when allocating blocks
for bigalloc + inline files that are being converted from inline to
extent mapped.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
media: dvbdev: adopts refcnt to avoid UAF
dvb_unregister_device() is known that prone to use-after-free.
That is, the cleanup from dvb_unregister_device() releases the dvb_device
even if there are pointers stored in file->private_data still refer to it.
This patch adds a reference counter into struct dvb_device and delays its
deallocation until no pointer refers to the object.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-15