Linux: >> Linux Kernel >> 6.1.51 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
net: atm: add lec_mutex
syzbot found its way in net/atm/lec.c, and found an error path
in lecd_attach() could leave a dangling pointer in dev_lec[].
Add a mutex to protect dev_lecp[] uses from lecd_attach(),
lec_vcc_attach() and lec_mcast_attach().
Following patch will use this mutex for /proc/net/atm/lec.
BUG: KASAN: slab-use-after-free in lecd_attach net/atm/lec.c:751 [inline]
BUG: KASAN: slab-use-after-free in lane_ioctl+0x2224/0x23e0 net/atm/lec.c:1008
Read of size 8 at addr ffff88807c7b8e68 by task syz.1.17/6142
CPU: 1 UID: 0 PID: 6142 Comm: syz.1.17 Not tainted 6.16.0-rc1-syzkaller-00239-g08215f5486ec #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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+0xcd/0x680 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
lecd_attach net/atm/lec.c:751 [inline]
lane_ioctl+0x2224/0x23e0 net/atm/lec.c:1008
do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159
sock_do_ioctl+0x118/0x280 net/socket.c:1190
sock_ioctl+0x227/0x6b0 net/socket.c:1311
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl fs/ioctl.c:893 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
Allocated by task 6132:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4328 [inline]
__kvmalloc_node_noprof+0x27b/0x620 mm/slub.c:5015
alloc_netdev_mqs+0xd2/0x1570 net/core/dev.c:11711
lecd_attach net/atm/lec.c:737 [inline]
lane_ioctl+0x17db/0x23e0 net/atm/lec.c:1008
do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159
sock_do_ioctl+0x118/0x280 net/socket.c:1190
sock_ioctl+0x227/0x6b0 net/socket.c:1311
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl fs/ioctl.c:893 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 6132:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kfree+0x2b4/0x4d0 mm/slub.c:4842
free_netdev+0x6c5/0x910 net/core/dev.c:11892
lecd_attach net/atm/lec.c:744 [inline]
lane_ioctl+0x1ce8/0x23e0 net/atm/lec.c:1008
do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159
sock_do_ioctl+0x118/0x280 net/socket.c:1190
sock_ioctl+0x227/0x6b0 net/socket.c:1311
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl fs/ioctl.c:893 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893
CVSS Score
7.8
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
mpls: Use rcu_dereference_rtnl() in mpls_route_input_rcu().
As syzbot reported [0], mpls_route_input_rcu() can be called
from mpls_getroute(), where is under RTNL.
net->mpls.platform_label is only updated under RTNL.
Let's use rcu_dereference_rtnl() in mpls_route_input_rcu() to
silence the splat.
[0]:
WARNING: suspicious RCU usage
6.15.0-rc7-syzkaller-00082-g5cdb2c77c4c3 #0 Not tainted
----------------------------
net/mpls/af_mpls.c:84 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz.2.4451/17730:
#0: ffffffff9012a3e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff9012a3e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x371/0xe90 net/core/rtnetlink.c:6961
stack backtrace:
CPU: 1 UID: 0 PID: 17730 Comm: syz.2.4451 Not tainted 6.15.0-rc7-syzkaller-00082-g5cdb2c77c4c3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
lockdep_rcu_suspicious+0x166/0x260 kernel/locking/lockdep.c:6865
mpls_route_input_rcu+0x1d4/0x200 net/mpls/af_mpls.c:84
mpls_getroute+0x621/0x1ea0 net/mpls/af_mpls.c:2381
rtnetlink_rcv_msg+0x3c9/0xe90 net/core/rtnetlink.c:6964
netlink_rcv_skb+0x16d/0x440 net/netlink/af_netlink.c:2534
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+0xa98/0xc70 net/socket.c:2566
___sys_sendmsg+0x134/0x1d0 net/socket.c:2620
__sys_sendmmsg+0x200/0x420 net/socket.c:2709
__do_sys_sendmmsg net/socket.c:2736 [inline]
__se_sys_sendmmsg net/socket.c:2733 [inline]
__x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2733
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0a2818e969
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:00007f0a28f52038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f0a283b5fa0 RCX: 00007f0a2818e969
RDX: 0000000000000003 RSI: 0000200000000080 RDI: 0000000000000003
RBP: 00007f0a28210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0a283b5fa0 R15: 00007ffce5e9f268
</TASK>
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
aoe: clean device rq_list in aoedev_downdev()
An aoe device's rq_list contains accepted block requests that are
waiting to be transmitted to the aoe target. This queue was added as
part of the conversion to blk_mq. However, the queue was not cleaned out
when an aoe device is downed which caused blk_mq_freeze_queue() to sleep
indefinitely waiting for those requests to complete, causing a hang. This
fix cleans out the queue before calling blk_mq_freeze_queue().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
arm64/ptrace: Fix stack-out-of-bounds read in regs_get_kernel_stack_nth()
KASAN reports a stack-out-of-bounds read in regs_get_kernel_stack_nth().
Call Trace:
[ 97.283505] BUG: KASAN: stack-out-of-bounds in regs_get_kernel_stack_nth+0xa8/0xc8
[ 97.284677] Read of size 8 at addr ffff800089277c10 by task 1.sh/2550
[ 97.285732]
[ 97.286067] CPU: 7 PID: 2550 Comm: 1.sh Not tainted 6.6.0+ #11
[ 97.287032] Hardware name: linux,dummy-virt (DT)
[ 97.287815] Call trace:
[ 97.288279] dump_backtrace+0xa0/0x128
[ 97.288946] show_stack+0x20/0x38
[ 97.289551] dump_stack_lvl+0x78/0xc8
[ 97.290203] print_address_description.constprop.0+0x84/0x3c8
[ 97.291159] print_report+0xb0/0x280
[ 97.291792] kasan_report+0x84/0xd0
[ 97.292421] __asan_load8+0x9c/0xc0
[ 97.293042] regs_get_kernel_stack_nth+0xa8/0xc8
[ 97.293835] process_fetch_insn+0x770/0xa30
[ 97.294562] kprobe_trace_func+0x254/0x3b0
[ 97.295271] kprobe_dispatcher+0x98/0xe0
[ 97.295955] kprobe_breakpoint_handler+0x1b0/0x210
[ 97.296774] call_break_hook+0xc4/0x100
[ 97.297451] brk_handler+0x24/0x78
[ 97.298073] do_debug_exception+0xac/0x178
[ 97.298785] el1_dbg+0x70/0x90
[ 97.299344] el1h_64_sync_handler+0xcc/0xe8
[ 97.300066] el1h_64_sync+0x78/0x80
[ 97.300699] kernel_clone+0x0/0x500
[ 97.301331] __arm64_sys_clone+0x70/0x90
[ 97.302084] invoke_syscall+0x68/0x198
[ 97.302746] el0_svc_common.constprop.0+0x11c/0x150
[ 97.303569] do_el0_svc+0x38/0x50
[ 97.304164] el0_svc+0x44/0x1d8
[ 97.304749] el0t_64_sync_handler+0x100/0x130
[ 97.305500] el0t_64_sync+0x188/0x190
[ 97.306151]
[ 97.306475] The buggy address belongs to stack of task 1.sh/2550
[ 97.307461] and is located at offset 0 in frame:
[ 97.308257] __se_sys_clone+0x0/0x138
[ 97.308910]
[ 97.309241] This frame has 1 object:
[ 97.309873] [48, 184) 'args'
[ 97.309876]
[ 97.310749] The buggy address belongs to the virtual mapping at
[ 97.310749] [ffff800089270000, ffff800089279000) created by:
[ 97.310749] dup_task_struct+0xc0/0x2e8
[ 97.313347]
[ 97.313674] The buggy address belongs to the physical page:
[ 97.314604] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14f69a
[ 97.315885] flags: 0x15ffffe00000000(node=1|zone=2|lastcpupid=0xfffff)
[ 97.316957] raw: 015ffffe00000000 0000000000000000 dead000000000122 0000000000000000
[ 97.318207] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
[ 97.319445] page dumped because: kasan: bad access detected
[ 97.320371]
[ 97.320694] Memory state around the buggy address:
[ 97.321511] ffff800089277b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 97.322681] ffff800089277b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 97.323846] >ffff800089277c00: 00 00 f1 f1 f1 f1 f1 f1 00 00 00 00 00 00 00 00
[ 97.325023] ^
[ 97.325683] ffff800089277c80: 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3 f3 f3
[ 97.326856] ffff800089277d00: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00
This issue seems to be related to the behavior of some gcc compilers and
was also fixed on the s390 architecture before:
commit d93a855c31b7 ("s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth()")
As described in that commit, regs_get_kernel_stack_nth() has confirmed that
`addr` is on the stack, so reading the value at `*addr` should be allowed.
Use READ_ONCE_NOCHECK() helper to silence the KASAN check for this case.
[will: Use '*addr' as the argument to READ_ONCE_NOCHECK()]
CVSS Score
7.1
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
iavf: get rid of the crit lock
Get rid of the crit lock.
That frees us from the error prone logic of try_locks.
Thanks to netdev_lock() by Jakub it is now easy, and in most cases we were
protected by it already - replace crit lock by netdev lock when it was not
the case.
Lockdep reports that we should cancel the work under crit_lock [splat1],
and that was the scheme we have mostly followed since [1] by Slawomir.
But when that is done we still got into deadlocks [splat2]. So instead
we should look at the bigger problem, namely "weird locking/scheduling"
of the iavf. The first step to fix that is to remove the crit lock.
I will followup with a -next series that simplifies scheduling/tasks.
Cancel the work without netdev lock (weird unlock+lock scheme),
to fix the [splat2] (which would be totally ugly if we would kept
the crit lock).
Extend protected part of iavf_watchdog_task() to include scheduling
more work.
Note that the removed comment in iavf_reset_task() was misplaced,
it belonged to inside of the removed if condition, so it's gone now.
[splat1] - w/o this patch - The deadlock during VF removal:
WARNING: possible circular locking dependency detected
sh/3825 is trying to acquire lock:
((work_completion)(&(&adapter->watchdog_task)->work)){+.+.}-{0:0}, at: start_flush_work+0x1a1/0x470
but task is already holding lock:
(&adapter->crit_lock){+.+.}-{4:4}, at: iavf_remove+0xd1/0x690 [iavf]
which lock already depends on the new lock.
[splat2] - when cancelling work under crit lock, w/o this series,
see [2] for the band aid attempt
WARNING: possible circular locking dependency detected
sh/3550 is trying to acquire lock:
((wq_completion)iavf){+.+.}-{0:0}, at: touch_wq_lockdep_map+0x26/0x90
but task is already holding lock:
(&dev->lock){+.+.}-{4:4}, at: iavf_remove+0xa6/0x6e0 [iavf]
which lock already depends on the new lock.
[1] fc2e6b3b132a ("iavf: Rework mutexes for better synchronisation")
[2] https://github.com/pkitszel/linux/commit/52dddbfc2bb60294083f5711a158a
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
fbdev: core: fbcvt: avoid division by 0 in fb_cvt_hperiod()
In fb_find_mode_cvt(), iff mode->refresh somehow happens to be 0x80000000,
cvt.f_refresh will become 0 when multiplying it by 2 due to overflow. It's
then passed to fb_cvt_hperiod(), where it's used as a divider -- division
by 0 will result in kernel oops. Add a sanity check for cvt.f_refresh to
avoid such overflow...
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
bus: fsl-mc: fix double-free on mc_dev
The blamed commit tried to simplify how the deallocations are done but,
in the process, introduced a double-free on the mc_dev variable.
In case the MC device is a DPRC, a new mc_bus is allocated and the
mc_dev variable is just a reference to one of its fields. In this
circumstance, on the error path only the mc_bus should be freed.
This commit introduces back the following checkpatch warning which is a
false-positive.
WARNING: kfree(NULL) is safe and this check is probably not required
+ if (mc_bus)
+ kfree(mc_bus);
CVSS Score
7.8
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pp: Fix potential NULL pointer dereference in atomctrl_initialize_mc_reg_table
The function atomctrl_initialize_mc_reg_table() and
atomctrl_initialize_mc_reg_table_v2_2() does not check the return
value of smu_atom_get_data_table(). If smu_atom_get_data_table()
fails to retrieve vram_info, it returns NULL which is later
dereferenced.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: eir: Fix possible crashes on eir_create_adv_data
eir_create_adv_data may attempt to add EIR_FLAGS and EIR_TX_POWER
without checking if that would fit.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: Fix NULL pointer deference on eir_get_service_data
The len parameter is considered optional so it can be NULL so it cannot
be used for skipping to next entry of EIR_SERVICE_DATA.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10