Linux: >> Linux Kernel >> 4.18.0 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
fs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev
Syzkaller reported the following issue:
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:1965:6
index -84 is out of range for type 's8[341]' (aka 'signed char[341]')
CPU: 1 PID: 4995 Comm: syz-executor146 Not tainted 6.4.0-rc6-syzkaller-00037-gb6dad5178cea #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
ubsan_epilogue lib/ubsan.c:217 [inline]
__ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348
dbAllocDmapLev+0x3e5/0x430 fs/jfs/jfs_dmap.c:1965
dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1809
dbAllocAG+0x28f/0x10b0 fs/jfs/jfs_dmap.c:1350
dbAlloc+0x658/0xca0 fs/jfs/jfs_dmap.c:874
dtSplitUp fs/jfs/jfs_dtree.c:974 [inline]
dtInsert+0xda7/0x6b00 fs/jfs/jfs_dtree.c:863
jfs_create+0x7b6/0xbb0 fs/jfs/namei.c:137
lookup_open fs/namei.c:3492 [inline]
open_last_lookups fs/namei.c:3560 [inline]
path_openat+0x13df/0x3170 fs/namei.c:3788
do_filp_open+0x234/0x490 fs/namei.c:3818
do_sys_openat2+0x13f/0x500 fs/open.c:1356
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x247/0x290 fs/open.c:1383
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f1f4e33f7e9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc21129578 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1f4e33f7e9
RDX: 000000000000275a RSI: 0000000020000040 RDI: 00000000ffffff9c
RBP: 00007f1f4e2ff080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1f4e2ff110
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
The bug occurs when the dbAllocDmapLev()function attempts to access
dp->tree.stree[leafidx + LEAFIND] while the leafidx value is negative.
To rectify this, the patch introduces a safeguard within the
dbAllocDmapLev() function. A check has been added to verify if leafidx is
negative. If it is, the function immediately returns an I/O error, preventing
any further execution that could potentially cause harm.
Tested via syzbot.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
powerpc/rtas_flash: allow user copy to flash block cache objects
With hardened usercopy enabled (CONFIG_HARDENED_USERCOPY=y), using the
/proc/powerpc/rtas/firmware_update interface to prepare a system
firmware update yields a BUG():
kernel BUG at mm/usercopy.c:102!
Oops: Exception in kernel mode, sig: 5 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
Modules linked in:
CPU: 0 PID: 2232 Comm: dd Not tainted 6.5.0-rc3+ #2
Hardware name: IBM,8408-E8E POWER8E (raw) 0x4b0201 0xf000004 of:IBM,FW860.50 (SV860_146) hv:phyp pSeries
NIP: c0000000005991d0 LR: c0000000005991cc CTR: 0000000000000000
REGS: c0000000148c76a0 TRAP: 0700 Not tainted (6.5.0-rc3+)
MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE> CR: 24002242 XER: 0000000c
CFAR: c0000000001fbd34 IRQMASK: 0
[ ... GPRs omitted ... ]
NIP usercopy_abort+0xa0/0xb0
LR usercopy_abort+0x9c/0xb0
Call Trace:
usercopy_abort+0x9c/0xb0 (unreliable)
__check_heap_object+0x1b4/0x1d0
__check_object_size+0x2d0/0x380
rtas_flash_write+0xe4/0x250
proc_reg_write+0xfc/0x160
vfs_write+0xfc/0x4e0
ksys_write+0x90/0x160
system_call_exception+0x178/0x320
system_call_common+0x160/0x2c4
The blocks of the firmware image are copied directly from user memory
to objects allocated from flash_block_cache, so flash_block_cache must
be created using kmem_cache_create_usercopy() to mark it safe for user
access.
[mpe: Trim and indent oops]
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
IB/hfi1: Fix possible panic during hotplug remove
During hotplug remove it is possible that the update counters work
might be pending, and may run after memory has been freed.
Cancel the update counters work before freeing memory.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.
syzkaller reported [0] memory leaks of an UDP socket and ZEROCOPY
skbs. We can reproduce the problem with these sequences:
sk = socket(AF_INET, SOCK_DGRAM, 0)
sk.setsockopt(SOL_SOCKET, SO_TIMESTAMPING, SOF_TIMESTAMPING_TX_SOFTWARE)
sk.setsockopt(SOL_SOCKET, SO_ZEROCOPY, 1)
sk.sendto(b'', MSG_ZEROCOPY, ('127.0.0.1', 53))
sk.close()
sendmsg() calls msg_zerocopy_alloc(), which allocates a skb, sets
skb->cb->ubuf.refcnt to 1, and calls sock_hold(). Here, struct
ubuf_info_msgzc indirectly holds a refcnt of the socket. When the
skb is sent, __skb_tstamp_tx() clones it and puts the clone into
the socket's error queue with the TX timestamp.
When the original skb is received locally, skb_copy_ubufs() calls
skb_unclone(), and pskb_expand_head() increments skb->cb->ubuf.refcnt.
This additional count is decremented while freeing the skb, but struct
ubuf_info_msgzc still has a refcnt, so __msg_zerocopy_callback() is
not called.
The last refcnt is not released unless we retrieve the TX timestamped
skb by recvmsg(). Since we clear the error queue in inet_sock_destruct()
after the socket's refcnt reaches 0, there is a circular dependency.
If we close() the socket holding such skbs, we never call sock_put()
and leak the count, sk, and skb.
TCP has the same problem, and commit e0c8bccd40fc ("net: stream:
purge sk_error_queue in sk_stream_kill_queues()") tried to fix it
by calling skb_queue_purge() during close(). However, there is a
small chance that skb queued in a qdisc or device could be put
into the error queue after the skb_queue_purge() call.
In __skb_tstamp_tx(), the cloned skb should not have a reference
to the ubuf to remove the circular dependency, but skb_clone() does
not call skb_copy_ubufs() for zerocopy skb. So, we need to call
skb_orphan_frags_rx() for the cloned skb to call skb_copy_ubufs().
[0]:
BUG: memory leak
unreferenced object 0xffff88800c6d2d00 (size 1152):
comm "syz-executor392", pid 264, jiffies 4294785440 (age 13.044s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 cd af e8 81 00 00 00 00 ................
02 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00 ...@............
backtrace:
[<0000000055636812>] sk_prot_alloc+0x64/0x2a0 net/core/sock.c:2024
[<0000000054d77b7a>] sk_alloc+0x3b/0x800 net/core/sock.c:2083
[<0000000066f3c7e0>] inet_create net/ipv4/af_inet.c:319 [inline]
[<0000000066f3c7e0>] inet_create+0x31e/0xe40 net/ipv4/af_inet.c:245
[<000000009b83af97>] __sock_create+0x2ab/0x550 net/socket.c:1515
[<00000000b9b11231>] sock_create net/socket.c:1566 [inline]
[<00000000b9b11231>] __sys_socket_create net/socket.c:1603 [inline]
[<00000000b9b11231>] __sys_socket_create net/socket.c:1588 [inline]
[<00000000b9b11231>] __sys_socket+0x138/0x250 net/socket.c:1636
[<000000004fb45142>] __do_sys_socket net/socket.c:1649 [inline]
[<000000004fb45142>] __se_sys_socket net/socket.c:1647 [inline]
[<000000004fb45142>] __x64_sys_socket+0x73/0xb0 net/socket.c:1647
[<0000000066999e0e>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<0000000066999e0e>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80
[<0000000017f238c1>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
BUG: memory leak
unreferenced object 0xffff888017633a00 (size 240):
comm "syz-executor392", pid 264, jiffies 4294785440 (age 13.044s)
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 2d 6d 0c 80 88 ff ff .........-m.....
backtrace:
[<000000002b1c4368>] __alloc_skb+0x229/0x320 net/core/skbuff.c:497
[<00000000143579a6>] alloc_skb include/linux/skbuff.h:1265 [inline]
[<00000000143579a6>] sock_omalloc+0xaa/0x190 net/core/sock.c:2596
[<00000000be626478>] msg_zerocopy_alloc net/core/skbuff.c:1294 [inline]
[<00000000be626478>]
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
ipv6: Add lwtunnel encap size of all siblings in nexthop calculation
In function rt6_nlmsg_size(), the length of nexthop is calculated
by multipling the nexthop length of fib6_info and the number of
siblings. However if the fib6_info has no lwtunnel but the siblings
have lwtunnels, the nexthop length is less than it should be, and
it will trigger a warning in inet6_rt_notify() as follows:
WARNING: CPU: 0 PID: 6082 at net/ipv6/route.c:6180 inet6_rt_notify+0x120/0x130
......
Call Trace:
<TASK>
fib6_add_rt2node+0x685/0xa30
fib6_add+0x96/0x1b0
ip6_route_add+0x50/0xd0
inet6_rtm_newroute+0x97/0xa0
rtnetlink_rcv_msg+0x156/0x3d0
netlink_rcv_skb+0x5a/0x110
netlink_unicast+0x246/0x350
netlink_sendmsg+0x250/0x4c0
sock_sendmsg+0x66/0x70
___sys_sendmsg+0x7c/0xd0
__sys_sendmsg+0x5d/0xb0
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
This bug can be reproduced by script:
ip -6 addr add 2002::2/64 dev ens2
ip -6 route add 100::/64 via 2002::1 dev ens2 metric 100
for i in 10 20 30 40 50 60 70;
do
ip link add link ens2 name ipv_$i type ipvlan
ip -6 addr add 2002::$i/64 dev ipv_$i
ifconfig ipv_$i up
done
for i in 10 20 30 40 50 60;
do
ip -6 route append 100::/64 encap ip6 dst 2002::$i via 2002::1
dev ipv_$i metric 100
done
ip -6 route append 100::/64 via 2002::1 dev ipv_70 metric 100
This patch fixes it by adding nexthop_len of every siblings using
rt6_nh_nlmsg_size().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
ubi: ubi_wl_put_peb: Fix infinite loop when wear-leveling work failed
Following process will trigger an infinite loop in ubi_wl_put_peb():
ubifs_bgt ubi_bgt
ubifs_leb_unmap
ubi_leb_unmap
ubi_eba_unmap_leb
ubi_wl_put_peb wear_leveling_worker
e1 = rb_entry(rb_first(&ubi->used)
e2 = get_peb_for_wl(ubi)
ubi_io_read_vid_hdr // return err (flash fault)
out_error:
ubi->move_from = ubi->move_to = NULL
wl_entry_destroy(ubi, e1)
ubi->lookuptbl[e->pnum] = NULL
retry:
e = ubi->lookuptbl[pnum]; // return NULL
if (e == ubi->move_from) { // NULL == NULL gets true
goto retry; // infinite loop !!!
$ top
PID USER PR NI VIRT RES SHR S %CPU %MEM COMMAND
7676 root 20 0 0 0 0 R 100.0 0.0 ubifs_bgt0_0
Fix it by:
1) Letting ubi_wl_put_peb() returns directly if wearl leveling entry has
been removed from 'ubi->lookuptbl'.
2) Using 'ubi->wl_lock' protecting wl entry deletion to preventing an
use-after-free problem for wl entry in ubi_wl_put_peb().
Fetch a reproducer in [Link].
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
iommu: Fix error unwind in iommu_group_alloc()
If either iommu_group_grate_file() fails then the
iommu_group is leaked.
Destroy it on these error paths.
Found by kselftest/iommu/iommufd_fail_nth
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu/gfx: disable gfx9 cp_ecc_error_irq only when enabling legacy gfx ras
gfx9 cp_ecc_error_irq is only enabled when legacy gfx ras is assert.
So in gfx_v9_0_hw_fini, interrupt disablement for cp_ecc_error_irq
should be executed under such condition, otherwise, an amdgpu_irq_put
calltrace will occur.
[ 7283.170322] RIP: 0010:amdgpu_irq_put+0x45/0x70 [amdgpu]
[ 7283.170964] RSP: 0018:ffff9a5fc3967d00 EFLAGS: 00010246
[ 7283.170967] RAX: ffff98d88afd3040 RBX: ffff98d89da20000 RCX: 0000000000000000
[ 7283.170969] RDX: 0000000000000000 RSI: ffff98d89da2bef8 RDI: ffff98d89da20000
[ 7283.170971] RBP: ffff98d89da20000 R08: ffff98d89da2ca18 R09: 0000000000000006
[ 7283.170973] R10: ffffd5764243c008 R11: 0000000000000000 R12: 0000000000001050
[ 7283.170975] R13: ffff98d89da38978 R14: ffffffff999ae15a R15: ffff98d880130105
[ 7283.170978] FS: 0000000000000000(0000) GS:ffff98d996f00000(0000) knlGS:0000000000000000
[ 7283.170981] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 7283.170983] CR2: 00000000f7a9d178 CR3: 00000001c42ea000 CR4: 00000000003506e0
[ 7283.170986] Call Trace:
[ 7283.170988] <TASK>
[ 7283.170989] gfx_v9_0_hw_fini+0x1c/0x6d0 [amdgpu]
[ 7283.171655] amdgpu_device_ip_suspend_phase2+0x101/0x1a0 [amdgpu]
[ 7283.172245] amdgpu_device_suspend+0x103/0x180 [amdgpu]
[ 7283.172823] amdgpu_pmops_freeze+0x21/0x60 [amdgpu]
[ 7283.173412] pci_pm_freeze+0x54/0xc0
[ 7283.173419] ? __pfx_pci_pm_freeze+0x10/0x10
[ 7283.173425] dpm_run_callback+0x98/0x200
[ 7283.173430] __device_suspend+0x164/0x5f0
v2: drop gfx11 as it's fixed in a different solution by retiring cp_ecc_irq funcs(Hawking)
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
iw_cxgb4: Fix potential NULL dereference in c4iw_fill_res_cm_id_entry()
This condition needs to match the previous "if (epcp->state == LISTEN) {"
exactly to avoid a NULL dereference of either "listen_ep" or "ep". The
problem is that "epcp" has been re-assigned so just testing
"if (epcp->state == LISTEN) {" a second time is not sufficient.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
ubifs: Fix memory leak in alloc_wbufs()
kmemleak reported a sequence of memory leaks, and show them as following:
unreferenced object 0xffff8881575f8400 (size 1024):
comm "mount", pid 19625, jiffies 4297119604 (age 20.383s)
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:
[<ffffffff8176cecd>] __kmalloc+0x4d/0x150
[<ffffffffa0406b2b>] ubifs_mount+0x307b/0x7170 [ubifs]
[<ffffffff819fa8fd>] legacy_get_tree+0xed/0x1d0
[<ffffffff81936f2d>] vfs_get_tree+0x7d/0x230
[<ffffffff819b2bd4>] path_mount+0xdd4/0x17b0
[<ffffffff819b37aa>] __x64_sys_mount+0x1fa/0x270
[<ffffffff83c14295>] do_syscall_64+0x35/0x80
[<ffffffff83e0006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
unreferenced object 0xffff8881798a6e00 (size 512):
comm "mount", pid 19677, jiffies 4297121912 (age 37.816s)
hex dump (first 32 bytes):
6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
backtrace:
[<ffffffff8176cecd>] __kmalloc+0x4d/0x150
[<ffffffffa0418342>] ubifs_wbuf_init+0x52/0x480 [ubifs]
[<ffffffffa0406ca5>] ubifs_mount+0x31f5/0x7170 [ubifs]
[<ffffffff819fa8fd>] legacy_get_tree+0xed/0x1d0
[<ffffffff81936f2d>] vfs_get_tree+0x7d/0x230
[<ffffffff819b2bd4>] path_mount+0xdd4/0x17b0
[<ffffffff819b37aa>] __x64_sys_mount+0x1fa/0x270
[<ffffffff83c14295>] do_syscall_64+0x35/0x80
[<ffffffff83e0006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
The problem is that the ubifs_wbuf_init() returns an error in the
loop which in the alloc_wbufs(), then the wbuf->buf and wbuf->inodes
that were successfully alloced before are not freed.
Fix it by adding error hanging path in alloc_wbufs() which frees
the memory alloced before when ubifs_wbuf_init() returns an error.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01