Security Bulletin
Summary
Multiple vulnerabilities have been identified in the Linux kernel affecting subsystems including InfiniBand (hfi1), RDMA, SquashFS, ATM networking, USB core, MPTCP, procfs, and framebuffer (fbdev). These issues involve race conditions, use-after-free scenarios, and out-of-bounds memory access, which could lead to system instability or denial of service under specific conditions.
Vulnerability Details
CVEID: CVE-2022-50865
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
tcp: fix a signed-integer-overflow bug in tcp_add_backlog()
The type of sk_rcvbuf and sk_sndbuf in struct sock is int, and
in tcp_add_backlog(), the variable limit is caculated by adding
sk_rcvbuf, sk_sndbuf and 64 * 1024, it may exceed the max value
of int and overflow. This patch reduces the limit budget by
halving the sndbuf to solve this issue since ACK packets are much
smaller than the payload.
CVSS Source: Red Hat
CVSS Base score: 7.5
CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVEID: CVE-2024-26766
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
IB/hfi1: Fix sdma.h tx-num_descs off-by-one error
Unfortunately the commit `fd8958efe877` introduced another error
causing the `descs` array to overflow. This reults in further crashes
easily reproducible by `sendmsg` system call.
[ 1080.836473] general protection fault, probably for non-canonical address 0x400300015528b00a: 0000 [#1] PREEMPT SMP PTI
[ 1080.869326] RIP: 0010:hfi1_ipoib_build_ib_tx_headers.constprop.0+0xe1/0x2b0 [hfi1]
--
[ 1080.974535] Call Trace:
[ 1080.976990] TASK
[ 1081.021929] hfi1_ipoib_send_dma_common+0x7a/0x2e0 [hfi1]
[ 1081.027364] hfi1_ipoib_send_dma_list+0x62/0x270 [hfi1]
[ 1081.032633] hfi1_ipoib_send+0x112/0x300 [hfi1]
[ 1081.042001] ipoib_start_xmit+0x2a9/0x2d0 [ib_ipoib]
[ 1081.046978] dev_hard_start_xmit+0xc4/0x210
--
[ 1081.148347] __sys_sendmsg+0x59/0xa0
crash ipoib_txreq 0xffff9cfeba229f00
struct ipoib_txreq {
txreq = {
list = {
next = 0xffff9cfeba229f00,
prev = 0xffff9cfeba229f00
},
descp = 0xffff9cfeba229f40,
coalesce_buf = 0x0,
wait = 0xffff9cfea4e69a48,
complete = 0xffffffffc0fe0760 hfi1_ipoib_sdma_complete,
packet_len = 0x46d,
tlen = 0x0,
num_desc = 0x0,
desc_limit = 0x6,
next_descq_idx = 0x45c,
coalesce_idx = 0x0,
flags = 0x0,
descs = {{
qw = {0x8024000120dffb00, 0x4} # SDMA_DESC0_FIRST_DESC_FLAG (bit 63)
}, {
qw = { 0x3800014231b108, 0x4}
}, {
qw = { 0x310000e4ee0fcf0, 0x8}
}, {
qw = { 0x3000012e9f8000, 0x8}
}, {
qw = { 0x59000dfb9d0000, 0x8}
}, {
qw = { 0x78000e02e40000, 0x8}
}}
},
sdma_hdr = 0x400300015528b000, invalid pointer in the tx request structure
sdma_status = 0x0, SDMA_DESC0_LAST_DESC_FLAG (bit 62)
complete = 0x0,
priv = 0x0,
txq = 0xffff9cfea4e69880,
skb = 0xffff9d099809f400
}
If an SDMA send consists of exactly 6 descriptors and requires dword
padding (in the 7th descriptor), the sdma_txreq descriptor array is not
properly expanded and the packet will overflow into the container
structure. This results in a panic when the send completion runs. The
exact panic varies depending on what elements of the container structure
get corrupted. The fix is to use the correct expression in
_pad_sdma_tx_descs() to test the need to expand the descriptor array.
With this patch the crashes are no longer reproducible and the machine is
stable.
CWE: CWE-193: Off-by-one Error
CVSS Source: NVD
CVSS Base score: 5.5
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
CVEID: CVE-2025-38022
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
RDMA/core: Fix "KASAN: slab-use-after-free Read in ib_register_device" problem
Call Trace:
__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
strlen+0x93/0xa0 lib/string.c:420
__fortify_strlen include/linux/fortify-string.h:268 [inline]
get_kobj_path_length lib/kobject.c:118 [inline]
kobject_get_path+0x3f/0x2a0 lib/kobject.c:158
kobject_uevent_env+0x289/0x1870 lib/kobject_uevent.c:545
ib_register_device drivers/infiniband/core/device.c:1472 [inline]
ib_register_device+0x8cf/0xe00 drivers/infiniband/core/device.c:1393
rxe_register_device+0x275/0x320 drivers/infiniband/sw/rxe/rxe_verbs.c:1552
rxe_net_add+0x8e/0xe0 drivers/infiniband/sw/rxe/rxe_net.c:550
rxe_newlink+0x70/0x190 drivers/infiniband/sw/rxe/rxe.c:225
nldev_newlink+0x3a3/0x680 drivers/infiniband/core/nldev.c:1796
rdma_nl_rcv_msg+0x387/0x6e0 drivers/infiniband/core/netlink.c:195
rdma_nl_rcv_skb.constprop.0.isra.0+0x2e5/0x450
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg net/socket.c:727 [inline]
____sys_sendmsg+0xa95/0xc70 net/socket.c:2566
___sys_sendmsg+0x134/0x1d0 net/socket.c:2620
__sys_sendmsg+0x16d/0x220 net/socket.c:2652
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
This problem is similar to the problem that the
commit 1d6a9e7449e2 ("RDMA/core: Fix use-after-free when rename device name")
fixes.
The root cause is: the function ib_device_rename() renames the name with
lock. But in the function kobject_uevent(), this name is accessed without
lock protection at the same time.
The solution is to add the lock protection when this name is accessed in
the function kobject_uevent().
CWE: CWE-416: Use After Free
CVSS Source: NVD
CVSS Base score: 7.8
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
CVEID: CVE-2025-38024
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix slab-use-after-free Read in rxe_queue_cleanup bug
Call Trace:
TASK
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x7d/0xa0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xcf/0x610 mm/kasan/report.c:489
kasan_report+0xb5/0xe0 mm/kasan/report.c:602
rxe_queue_cleanup+0xd0/0xe0 drivers/infiniband/sw/rxe/rxe_queue.c:195
rxe_cq_cleanup+0x3f/0x50 drivers/infiniband/sw/rxe/rxe_cq.c:132
__rxe_cleanup+0x168/0x300 drivers/infiniband/sw/rxe/rxe_pool.c:232
rxe_create_cq+0x22e/0x3a0 drivers/infiniband/sw/rxe/rxe_verbs.c:1109
create_cq+0x658/0xb90 drivers/infiniband/core/uverbs_cmd.c:1052
ib_uverbs_create_cq+0xc7/0x120 drivers/infiniband/core/uverbs_cmd.c:1095
ib_uverbs_write+0x969/0xc90 drivers/infiniband/core/uverbs_main.c:679
vfs_write fs/read_write.c:677 [inline]
vfs_write+0x26a/0xcc0 fs/read_write.c:659
ksys_write+0x1b8/0x200 fs/read_write.c:731
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xaa/0x1b0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
In the function rxe_create_cq, when rxe_cq_from_init fails, the function
rxe_cleanup will be called to handle the allocated resources. In fact,
some memory resources have already been freed in the function
rxe_cq_from_init. Thus, this problem will occur.
The solution is to let rxe_cleanup do all the work.
CWE: CWE-416: Use After Free
CVSS Source: NVD
CVSS Base score: 7.8
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
CVEID: CVE-2025-38415
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
Squashfs: check return result of sb_min_blocksize
Syzkaller reports an "UBSAN: shift-out-of-bounds in squashfs_bio_read" bug.
Syzkaller forks multiple processes which after mounting the Squashfs
filesystem, issues an ioctl("/dev/loop0", LOOP_SET_BLOCK_SIZE, 0x8000).
Now if this ioctl occurs at the same time another process is in the
process of mounting a Squashfs filesystem on /dev/loop0, the failure
occurs. When this happens the following code in squashfs_fill_super()
fails.
----
msblk-devblksize = sb_min_blocksize(sb, SQUASHFS_DEVBLK_SIZE);
msblk-devblksize_log2 = ffz(~msblk-devblksize);
----
sb_min_blocksize() returns 0, which means msblk-devblksize is set to 0.
As a result, ffz(~msblk-devblksize) returns 64, and msblk-devblksize_log2
is set to 64.
This subsequently causes the
UBSAN: shift-out-of-bounds in fs/squashfs/block.c:195:36
shift exponent 64 is too large for 64-bit type 'u64' (aka
'unsigned long long')
This commit adds a check for a 0 return by sb_min_blocksize().
CWE: CWE-787: Out-of-bounds Write
CVSS Source: NVD
CVSS Base score: 7.8
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
CVEID: CVE-2025-38459
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
atm: clip: Fix infinite recursive call of clip_push().
syzbot reported the splat below. [0]
This happens if we call ioctl(ATMARP_MKIP) more than once.
During the first call, clip_mkip() sets clip_push() to vcc-push(),
and the second call copies it to clip_vcc-old_push().
Later, when the socket is close()d, vcc_destroy_socket() passes
NULL skb to clip_push(), which calls clip_vcc-old_push(),
triggering the infinite recursion.
Let's prevent the second ioctl(ATMARP_MKIP) by checking
vcc-user_back, which is allocated by the first call as clip_vcc.
Note also that we use lock_sock() to prevent racy calls.
[0]:
BUG: TASK stack guard page was hit at ffffc9000d66fff8 (stack is ffffc9000d670000..ffffc9000d678000)
Oops: stack guard page: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5322 Comm: syz.0.0 Not tainted 6.16.0-rc4-syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:clip_push+0x5/0x720 net/atm/clip.c:191
Code: e0 8f aa 8c e8 1c ad 5b fa eb ae 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 20 48 89 f3 49 89 fd 48 bd 00
RSP: 0018:ffffc9000d670000 EFLAGS: 00010246
RAX: 1ffff1100235a4a5 RBX: ffff888011ad2508 RCX: ffff8880003c0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888037f01000
RBP: dffffc0000000000 R08: ffffffff8fa104f7 R09: 1ffffffff1f4209e
R10: dffffc0000000000 R11: ffffffff8a99b300 R12: ffffffff8a99b300
R13: ffff888037f01000 R14: ffff888011ad2500 R15: ffff888037f01578
FS: 000055557ab6d500(0000) GS:ffff88808d250000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc9000d66fff8 CR3: 0000000043172000 CR4: 0000000000352ef0
Call Trace:
TASK
clip_push+0x6dc/0x720 net/atm/clip.c:200
clip_push+0x6dc/0x720 net/atm/clip.c:200
clip_push+0x6dc/0x720 net/atm/clip.c:200
...
clip_push+0x6dc/0x720 net/atm/clip.c:200
clip_push+0x6dc/0x720 net/atm/clip.c:200
clip_push+0x6dc/0x720 net/atm/clip.c:200
vcc_destroy_socket net/atm/common.c:183 [inline]
vcc_release+0x157/0x460 net/atm/common.c:205
__sock_release net/socket.c:647 [inline]
sock_close+0xc0/0x240 net/socket.c:1391
__fput+0x449/0xa70 fs/file_table.c:465
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff31c98e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 48 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffb5aa1f78 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 0000000000012747 RCX: 00007ff31c98e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007ff31cbb7ba0 R08: 0000000000000001 R09: 0000000db5aa226f
R10: 00007ff31c7ff030 R11: 0000000000000246 R12: 00007ff31cbb608c
R13: 00007ff31cbb6080 R14: ffffffffffffffff R15: 00007fffb5aa2090
/TASK
Modules linked in:
CWE: CWE-674: Uncontrolled Recursion
CVSS Source: NVD
CVSS Base score: 7.8
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
CVEID: CVE-2025-39760
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
usb: core: config: Prevent OOB read in SS endpoint companion parsing
usb_parse_ss_endpoint_companion() checks descriptor type before length,
enabling a potentially odd read outside of the buffer size.
Fix this up by checking the size first before looking at any of the
fields in the descriptor.
CWE: CWE-125: Out-of-bounds Read
CVSS Source: NVD
CVSS Base score: 7.1
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H)
CVEID: CVE-2025-40258
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix race condition in mptcp_schedule_work()
syzbot reported use-after-free in mptcp_schedule_work() [1]
Issue here is that mptcp_schedule_work() schedules a work,
then gets a refcount on sk-sk_refcnt if the work was scheduled.
This refcount will be released by mptcp_worker().
[A] if (schedule_work(...)) {
[B] sock_hold(sk);
return true;
}
Problem is that mptcp_worker() can run immediately and complete before [B]
We need instead :
sock_hold(sk);
if (schedule_work(...))
return true;
sock_put(sk);
[1]
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 29 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25
Call Trace:
TASK
__refcount_add include/linux/refcount.h:-1 [inline]
__refcount_inc include/linux/refcount.h:366 [inline]
refcount_inc include/linux/refcount.h:383 [inline]
sock_hold include/net/sock.h:816 [inline]
mptcp_schedule_work+0x164/0x1a0 net/mptcp/protocol.c:943
mptcp_tout_timer+0x21/0xa0 net/mptcp/protocol.c:2316
call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
expire_timers kernel/time/timer.c:1798 [inline]
__run_timers kernel/time/timer.c:2372 [inline]
__run_timer_base+0x648/0x970 kernel/time/timer.c:2384
run_timer_base kernel/time/timer.c:2393 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
handle_softirqs+0x22f/0x710 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
run_ktimerd+0xcf/0x190 kernel/softirq.c:1138
smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
CVSS Source: Red Hat
CVSS Base score: 7.8
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
CVEID: CVE-2025-40271
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
fs/proc: fix uaf in proc_readdir_de()
Pde is erased from subdir rbtree through rb_erase(), but not set the node
to EMPTY, which may result in uaf access. We should use RB_CLEAR_NODE()
set the erased node to EMPTY, then pde_subdir_next() will return NULL to
avoid uaf access.
We found an uaf issue while using stress-ng testing, need to run testcase
getdent and tun in the same time. The steps of the issue is as follows:
1) use getdent to traverse dir /proc/pid/net/dev_snmp6/, and current
pde is tun3;
2) in the [time windows] unregister netdevice tun3 and tun2, and erase
them from rbtree. erase tun3 first, and then erase tun2. the
pde(tun2) will be released to slab;
3) continue to getdent process, then pde_subdir_next() will return
pde(tun2) which is released, it will case uaf access.
CPU 0 | CPU 1
-------------------------------------------------------------------------
traverse dir /proc/pid/net/dev_snmp6/ | unregister_netdevice(tun-dev) //tun3 tun2
sys_getdents64() |
iterate_dir() |
proc_readdir() |
proc_readdir_de() | snmp6_unregister_dev()
pde_get(de); | proc_remove()
read_unlock(&proc_subdir_lock); | remove_proc_subtree()
| write_lock(&proc_subdir_lock);
[time window] | rb_erase(&root-subdir_node, &parent-subdir);
| write_unlock(&proc_subdir_lock);
read_lock(&proc_subdir_lock); |
next = pde_subdir_next(de); |
pde_put(de); |
de = next; //UAF |
rbtree of dev_snmp6
|
pde(tun3)
/ \
NULL pde(tun2)
CVSS Source: Red Hat
CVSS Base score: 7
CVSS Vector: (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H)
CVEID: CVE-2025-40322
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
fbdev: bitblit: bound-check glyph index in bit_putcs*
bit_putcs_aligned()/unaligned() derived the glyph pointer from the
character value masked by 0xff/0x1ff, which may exceed the actual font's
glyph count and read past the end of the built-in font array.
Clamp the index to the actual glyph count before computing the address.
This fixes a global out-of-bounds read reported by syzbot.
CVSS Source: Red Hat
CVSS Base score: 7.1
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H)
Affected Products and Versions
| Affected Product(s) | Version(s) |
| Technical Support Appliance | All |
Remediation/Fixes
Update the IBM Technical Support Appliance to 3.1.2. Refer to online support documentation on how to perform an update.
Workarounds and Mitigations
None
Get Notified about Future Security Bulletins
References
Acknowledgement
Change History
26 Mar 2026: Initial Publication
*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.
Disclaimer
According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY. In addition to other efforts to address potential vulnerabilities, IBM periodically updates the record of components contained in our product offerings. As part of that effort, if IBM identifies previously unidentified packages in a product/service inventory, we address relevant vulnerabilities regardless of CVE date. Inclusion of an older CVEID does not demonstrate that the referenced product has been used by IBM since that date, nor that IBM was aware of a vulnerability as of that date. We are making clients aware of relevant vulnerabilities as we become aware of them. "Affected Products and Versions" referenced in IBM Security Bulletins are intended to be only products and versions that are supported by IBM and have not passed their end-of-support or warranty date. Thus, failure to reference unsupported or extended-support products and versions in this Security Bulletin does not constitute a determination by IBM that they are unaffected by the vulnerability. Reference to one or more unsupported versions in this Security Bulletin shall not create an obligation for IBM to provide fixes for any unsupported or extended-support products or versions.
Document Location
Worldwide
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Document Information
Modified date:
26 March 2026
Initial Publish date:
26 March 2026
UID
ibm17267686