Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix null-ptr-deref in ext4_write_info
I caught a null-ptr-deref bug as follows:
==================================================================
KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
CPU: 1 PID: 1589 Comm: umount Not tainted 5.10.0-02219-dirty #339
RIP: 0010:ext4_write_info+0x53/0x1b0
[...]
Call Trace:
dquot_writeback_dquots+0x341/0x9a0
ext4_sync_fs+0x19e/0x800
__sync_filesystem+0x83/0x100
sync_filesystem+0x89/0xf0
generic_shutdown_super+0x79/0x3e0
kill_block_super+0xa1/0x110
deactivate_locked_super+0xac/0x130
deactivate_super+0xb6/0xd0
cleanup_mnt+0x289/0x400
__cleanup_mnt+0x16/0x20
task_work_run+0x11c/0x1c0
exit_to_user_mode_prepare+0x203/0x210
syscall_exit_to_user_mode+0x5b/0x3a0
do_syscall_64+0x59/0x70
entry_SYSCALL_64_after_hwframe+0x44/0xa9
==================================================================
Above issue may happen as follows:
-------------------------------------
exit_to_user_mode_prepare
task_work_run
__cleanup_mnt
cleanup_mnt
deactivate_super
deactivate_locked_super
kill_block_super
generic_shutdown_super
shrink_dcache_for_umount
dentry = sb->s_root
sb->s_root = NULL <--- Here set NULL
sync_filesystem
__sync_filesystem
sb->s_op->sync_fs > ext4_sync_fs
dquot_writeback_dquots
sb->dq_op->write_info > ext4_write_info
ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2)
d_inode(sb->s_root)
s_root->d_inode <--- Null pointer dereference
To solve this problem, we use ext4_journal_start_sb directly
to avoid s_root being used.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
ext4: init quota for 'old.inode' in 'ext4_rename'
Syzbot found the following issue:
ext4_parse_param: s_want_extra_isize=128
ext4_inode_info_init: s_want_extra_isize=32
ext4_rename: old.inode=ffff88823869a2c8 old.dir=ffff888238699828 new.inode=ffff88823869d7e8 new.dir=ffff888238699828
__ext4_mark_inode_dirty: inode=ffff888238699828 ea_isize=32 want_ea_size=128
__ext4_mark_inode_dirty: inode=ffff88823869a2c8 ea_isize=32 want_ea_size=128
ext4_xattr_block_set: inode=ffff88823869a2c8
------------[ cut here ]------------
WARNING: CPU: 13 PID: 2234 at fs/ext4/xattr.c:2070 ext4_xattr_block_set.cold+0x22/0x980
Modules linked in:
RIP: 0010:ext4_xattr_block_set.cold+0x22/0x980
RSP: 0018:ffff888227d3f3b0 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff88823007a000 RCX: 0000000000000000
RDX: 0000000000000a03 RSI: 0000000000000040 RDI: ffff888230078178
RBP: 0000000000000000 R08: 000000000000002c R09: ffffed1075c7df8e
R10: ffff8883ae3efc6b R11: ffffed1075c7df8d R12: 0000000000000000
R13: ffff88823869a2c8 R14: ffff8881012e0460 R15: dffffc0000000000
FS: 00007f350ac1f740(0000) GS:ffff8883ae200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f350a6ed6a0 CR3: 0000000237456000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
? ext4_xattr_set_entry+0x3b7/0x2320
? ext4_xattr_block_set+0x0/0x2020
? ext4_xattr_set_entry+0x0/0x2320
? ext4_xattr_check_entries+0x77/0x310
? ext4_xattr_ibody_set+0x23b/0x340
ext4_xattr_move_to_block+0x594/0x720
ext4_expand_extra_isize_ea+0x59a/0x10f0
__ext4_expand_extra_isize+0x278/0x3f0
__ext4_mark_inode_dirty.cold+0x347/0x410
ext4_rename+0xed3/0x174f
vfs_rename+0x13a7/0x2510
do_renameat2+0x55d/0x920
__x64_sys_rename+0x7d/0xb0
do_syscall_64+0x3b/0xa0
entry_SYSCALL_64_after_hwframe+0x72/0xdc
As 'ext4_rename' will modify 'old.inode' ctime and mark inode dirty,
which may trigger expand 'extra_isize' and allocate block. If inode
didn't init quota will lead to warning. To solve above issue, init
'old.inode' firstly in 'ext4_rename'.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
mmc: rtsx_usb_sdmmc: fix return value check of mmc_add_host()
mmc_add_host() may return error, if we ignore its return value, the memory
that allocated in mmc_alloc_host() will be leaked and it will lead a kernel
crash because of deleting not added device in the remove path.
So fix this by checking the return value and calling mmc_free_host() in the
error path, besides, led_classdev_unregister() and pm_runtime_disable() also
need be called.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
nfsd: Fix a memory leak in an error handling path
If this memdup_user() call fails, the memory allocated in a previous call
a few lines above should be freed. Otherwise it leaks.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
misc: tifm: fix possible memory leak in tifm_7xx1_switch_media()
If device_register() returns error in tifm_7xx1_switch_media(),
name of kobject which is allocated in dev_set_name() called in device_add()
is leaked.
Never directly free @dev after calling device_register(), even
if it returned an error! Always use put_device() to give up the
reference initialized.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
scsi: target: iscsi: Fix a race condition between login_work and the login thread
In case a malicious initiator sends some random data immediately after a
login PDU; the iscsi_target_sk_data_ready() callback will schedule the
login_work and, at the same time, the negotiation may end without clearing
the LOGIN_FLAGS_INITIAL_PDU flag (because no additional PDU exchanges are
required to complete the login).
The login has been completed but the login_work function will find the
LOGIN_FLAGS_INITIAL_PDU flag set and will never stop from rescheduling
itself; at this point, if the initiator drops the connection, the
iscsit_conn structure will be freed, login_work will dereference a released
socket structure and the kernel crashes.
BUG: kernel NULL pointer dereference, address: 0000000000000230
PF: supervisor write access in kernel mode
PF: error_code(0x0002) - not-present page
Workqueue: events iscsi_target_do_login_rx [iscsi_target_mod]
RIP: 0010:_raw_read_lock_bh+0x15/0x30
Call trace:
iscsi_target_do_login_rx+0x75/0x3f0 [iscsi_target_mod]
process_one_work+0x1e8/0x3c0
Fix this bug by forcing login_work to stop after the login has been
completed and the socket callbacks have been restored.
Add a comment to clearify the return values of iscsi_target_do_login()
CVSS Score
4.7
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix xid leak in cifs_create()
If the cifs already shutdown, we should free the xid before return,
otherwise, the xid will be leaked.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
media: vimc: Fix wrong function called when vimc_init() fails
In vimc_init(), when platform_driver_register(&vimc_pdrv) fails,
platform_driver_unregister(&vimc_pdrv) is wrongly called rather than
platform_device_unregister(&vimc_pdev), which causes kernel warning:
Unexpected driver unregister!
WARNING: CPU: 1 PID: 14517 at drivers/base/driver.c:270 driver_unregister+0x8f/0xb0
RIP: 0010:driver_unregister+0x8f/0xb0
Call Trace:
<TASK>
vimc_init+0x7d/0x1000 [vimc]
do_one_initcall+0xd0/0x4e0
do_init_module+0x1cf/0x6b0
load_module+0x65c2/0x7820
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
cifs: fix oops during encryption
When running xfstests against Azure the following oops occurred on an
arm64 system
Unable to handle kernel write to read-only memory at virtual address
ffff0001221cf000
Mem abort info:
ESR = 0x9600004f
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x0f: level 3 permission fault
Data abort info:
ISV = 0, ISS = 0x0000004f
CM = 0, WnR = 1
swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000000294f3000
[ffff0001221cf000] pgd=18000001ffff8003, p4d=18000001ffff8003,
pud=18000001ff82e003, pmd=18000001ff71d003, pte=00600001221cf787
Internal error: Oops: 9600004f [#1] PREEMPT SMP
...
pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--)
pc : __memcpy+0x40/0x230
lr : scatterwalk_copychunks+0xe0/0x200
sp : ffff800014e92de0
x29: ffff800014e92de0 x28: ffff000114f9de80 x27: 0000000000000008
x26: 0000000000000008 x25: ffff800014e92e78 x24: 0000000000000008
x23: 0000000000000001 x22: 0000040000000000 x21: ffff000000000000
x20: 0000000000000001 x19: ffff0001037c4488 x18: 0000000000000014
x17: 235e1c0d6efa9661 x16: a435f9576b6edd6c x15: 0000000000000058
x14: 0000000000000001 x13: 0000000000000008 x12: ffff000114f2e590
x11: ffffffffffffffff x10: 0000040000000000 x9 : ffff8000105c3580
x8 : 2e9413b10000001a x7 : 534b4410fb86b005 x6 : 534b4410fb86b005
x5 : ffff0001221cf008 x4 : ffff0001037c4490 x3 : 0000000000000001
x2 : 0000000000000008 x1 : ffff0001037c4488 x0 : ffff0001221cf000
Call trace:
__memcpy+0x40/0x230
scatterwalk_map_and_copy+0x98/0x100
crypto_ccm_encrypt+0x150/0x180
crypto_aead_encrypt+0x2c/0x40
crypt_message+0x750/0x880
smb3_init_transform_rq+0x298/0x340
smb_send_rqst.part.11+0xd8/0x180
smb_send_rqst+0x3c/0x100
compound_send_recv+0x534/0xbc0
smb2_query_info_compound+0x32c/0x440
smb2_set_ea+0x438/0x4c0
cifs_xattr_set+0x5d4/0x7c0
This is because in scatterwalk_copychunks(), we attempted to write to
a buffer (@sign) that was allocated in the stack (vmalloc area) by
crypt_message() and thus accessing its remaining 8 (x2) bytes ended up
crossing a page boundary.
To simply fix it, we could just pass @sign kmalloc'd from
crypt_message() and then we're done. Luckily, we don't seem to pass
any other vmalloc'd buffers in smb_rqst::rq_iov...
Instead, let's map the correct pages and offsets from vmalloc buffers
as well in cifs_sg_set_buf() and then avoiding such oopses.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
floppy: Fix memory leak in do_floppy_init()
A memory leak was reported when floppy_alloc_disk() failed in
do_floppy_init().
unreferenced object 0xffff888115ed25a0 (size 8):
comm "modprobe", pid 727, jiffies 4295051278 (age 25.529s)
hex dump (first 8 bytes):
00 ac 67 5b 81 88 ff ff ..g[....
backtrace:
[<000000007f457abb>] __kmalloc_node+0x4c/0xc0
[<00000000a87bfa9e>] blk_mq_realloc_tag_set_tags.part.0+0x6f/0x180
[<000000006f02e8b1>] blk_mq_alloc_tag_set+0x573/0x1130
[<0000000066007fd7>] 0xffffffffc06b8b08
[<0000000081f5ac40>] do_one_initcall+0xd0/0x4f0
[<00000000e26d04ee>] do_init_module+0x1a4/0x680
[<000000001bb22407>] load_module+0x6249/0x7110
[<00000000ad31ac4d>] __do_sys_finit_module+0x140/0x200
[<000000007bddca46>] do_syscall_64+0x35/0x80
[<00000000b5afec39>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
unreferenced object 0xffff88810fc30540 (size 32):
comm "modprobe", pid 727, jiffies 4295051278 (age 25.529s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<000000007f457abb>] __kmalloc_node+0x4c/0xc0
[<000000006b91eab4>] blk_mq_alloc_tag_set+0x393/0x1130
[<0000000066007fd7>] 0xffffffffc06b8b08
[<0000000081f5ac40>] do_one_initcall+0xd0/0x4f0
[<00000000e26d04ee>] do_init_module+0x1a4/0x680
[<000000001bb22407>] load_module+0x6249/0x7110
[<00000000ad31ac4d>] __do_sys_finit_module+0x140/0x200
[<000000007bddca46>] do_syscall_64+0x35/0x80
[<00000000b5afec39>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
If the floppy_alloc_disk() failed, disks of current drive will not be set,
thus the lastest allocated set->tag cannot be freed in the error handling
path. A simple call graph shown as below:
floppy_module_init()
floppy_init()
do_floppy_init()
for (drive = 0; drive < N_DRIVE; drive++)
blk_mq_alloc_tag_set()
blk_mq_alloc_tag_set_tags()
blk_mq_realloc_tag_set_tags() # set->tag allocated
floppy_alloc_disk()
blk_mq_alloc_disk() # error occurred, disks failed to allocated
->out_put_disk:
for (drive = 0; drive < N_DRIVE; drive++)
if (!disks[drive][0]) # the last disks is not set and loop break
break;
blk_mq_free_tag_set() # the latest allocated set->tag leaked
Fix this problem by free the set->tag of current drive before jump to
error handling path.
[efremov: added stable list, changed title]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16