Linux: >> Linux Kernel >> 5.6.19 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
i2c: cros-ec-tunnel: defer probe if parent EC is not present
When i2c-cros-ec-tunnel and the EC driver are built-in, the EC parent
device will not be found, leading to NULL pointer dereference.
That can also be reproduced by unbinding the controller driver and then
loading i2c-cros-ec-tunnel module (or binding the device).
[ 271.991245] BUG: kernel NULL pointer dereference, address: 0000000000000058
[ 271.998215] #PF: supervisor read access in kernel mode
[ 272.003351] #PF: error_code(0x0000) - not-present page
[ 272.008485] PGD 0 P4D 0
[ 272.011022] Oops: Oops: 0000 [#1] SMP NOPTI
[ 272.015207] CPU: 0 UID: 0 PID: 3859 Comm: insmod Tainted: G S 6.15.0-rc1-00004-g44722359ed83 #30 PREEMPT(full) 3c7fb39a552e7d949de2ad921a7d6588d3a4fdc5
[ 272.030312] Tainted: [S]=CPU_OUT_OF_SPEC
[ 272.034233] Hardware name: HP Berknip/Berknip, BIOS Google_Berknip.13434.356.0 05/17/2021
[ 272.042400] RIP: 0010:ec_i2c_probe+0x2b/0x1c0 [i2c_cros_ec_tunnel]
[ 272.048577] Code: 1f 44 00 00 41 57 41 56 41 55 41 54 53 48 83 ec 10 65 48 8b 05 06 a0 6c e7 48 89 44 24 08 4c 8d 7f 10 48 8b 47 50 4c 8b 60 78 <49> 83 7c 24 58 00 0f 84 2f 01 00 00 48 89 fb be 30 06 00 00 4c 9
[ 272.067317] RSP: 0018:ffffa32082a03940 EFLAGS: 00010282
[ 272.072541] RAX: ffff969580b6a810 RBX: ffff969580b68c10 RCX: 0000000000000000
[ 272.079672] RDX: 0000000000000000 RSI: 0000000000000282 RDI: ffff969580b68c00
[ 272.086804] RBP: 00000000fffffdfb R08: 0000000000000000 R09: 0000000000000000
[ 272.093936] R10: 0000000000000000 R11: ffffffffc0600000 R12: 0000000000000000
[ 272.101067] R13: ffffffffa666fbb8 R14: ffffffffc05b5528 R15: ffff969580b68c10
[ 272.108198] FS: 00007b930906fc40(0000) GS:ffff969603149000(0000) knlGS:0000000000000000
[ 272.116282] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 272.122024] CR2: 0000000000000058 CR3: 000000012631c000 CR4: 00000000003506f0
[ 272.129155] Call Trace:
[ 272.131606] <TASK>
[ 272.133709] ? acpi_dev_pm_attach+0xdd/0x110
[ 272.137985] platform_probe+0x69/0xa0
[ 272.141652] really_probe+0x152/0x310
[ 272.145318] __driver_probe_device+0x77/0x110
[ 272.149678] driver_probe_device+0x1e/0x190
[ 272.153864] __driver_attach+0x10b/0x1e0
[ 272.157790] ? driver_attach+0x20/0x20
[ 272.161542] bus_for_each_dev+0x107/0x150
[ 272.165553] bus_add_driver+0x15d/0x270
[ 272.169392] driver_register+0x65/0x110
[ 272.173232] ? cleanup_module+0xa80/0xa80 [i2c_cros_ec_tunnel 3a00532f3f4af4a9eade753f86b0f8dd4e4e5698]
[ 272.182617] do_one_initcall+0x110/0x350
[ 272.186543] ? security_kernfs_init_security+0x49/0xd0
[ 272.191682] ? __kernfs_new_node+0x1b9/0x240
[ 272.195954] ? security_kernfs_init_security+0x49/0xd0
[ 272.201093] ? __kernfs_new_node+0x1b9/0x240
[ 272.205365] ? kernfs_link_sibling+0x105/0x130
[ 272.209810] ? kernfs_next_descendant_post+0x1c/0xa0
[ 272.214773] ? kernfs_activate+0x57/0x70
[ 272.218699] ? kernfs_add_one+0x118/0x160
[ 272.222710] ? __kernfs_create_file+0x71/0xa0
[ 272.227069] ? sysfs_add_bin_file_mode_ns+0xd6/0x110
[ 272.232033] ? internal_create_group+0x453/0x4a0
[ 272.236651] ? __vunmap_range_noflush+0x214/0x2d0
[ 272.241355] ? __free_frozen_pages+0x1dc/0x420
[ 272.245799] ? free_vmap_area_noflush+0x10a/0x1c0
[ 272.250505] ? load_module+0x1509/0x16f0
[ 272.254431] do_init_module+0x60/0x230
[ 272.258181] __se_sys_finit_module+0x27a/0x370
[ 272.262627] do_syscall_64+0x6a/0xf0
[ 272.266206] ? do_syscall_64+0x76/0xf0
[ 272.269956] ? irqentry_exit_to_user_mode+0x79/0x90
[ 272.274836] entry_SYSCALL_64_after_hwframe+0x55/0x5d
[ 272.279887] RIP: 0033:0x7b9309168d39
[ 272.283466] Code: 5b 41 5c 5d c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 8b 0d af 40 0c 00 f7 d8 64 89 01 8
[ 272.302210] RSP: 002b:00007fff50f1a288 EFLAGS: 00000246 ORIG_RAX: 000
---truncated---
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: free routing table on probe failure
If complete = true in dsa_tree_setup(), it means that we are the last
switch of the tree which is successfully probing, and we should be
setting up all switches from our probe path.
After "complete" becomes true, dsa_tree_setup_cpu_ports() or any
subsequent function may fail. If that happens, the entire tree setup is
in limbo: the first N-1 switches have successfully finished probing
(doing nothing but having allocated persistent memory in the tree's
dst->ports, and maybe dst->rtable), and switch N failed to probe, ending
the tree setup process before anything is tangible from the user's PoV.
If switch N fails to probe, its memory (ports) will be freed and removed
from dst->ports. However, the dst->rtable elements pointing to its ports,
as created by dsa_link_touch(), will remain there, and will lead to
use-after-free if dereferenced.
If dsa_tree_setup_switches() returns -EPROBE_DEFER, which is entirely
possible because that is where ds->ops->setup() is, we get a kasan
report like this:
==================================================================
BUG: KASAN: slab-use-after-free in mv88e6xxx_setup_upstream_port+0x240/0x568
Read of size 8 at addr ffff000004f56020 by task kworker/u8:3/42
Call trace:
__asan_report_load8_noabort+0x20/0x30
mv88e6xxx_setup_upstream_port+0x240/0x568
mv88e6xxx_setup+0xebc/0x1eb0
dsa_register_switch+0x1af4/0x2ae0
mv88e6xxx_register_switch+0x1b8/0x2a8
mv88e6xxx_probe+0xc4c/0xf60
mdio_probe+0x78/0xb8
really_probe+0x2b8/0x5a8
__driver_probe_device+0x164/0x298
driver_probe_device+0x78/0x258
__device_attach_driver+0x274/0x350
Allocated by task 42:
__kasan_kmalloc+0x84/0xa0
__kmalloc_cache_noprof+0x298/0x490
dsa_switch_touch_ports+0x174/0x3d8
dsa_register_switch+0x800/0x2ae0
mv88e6xxx_register_switch+0x1b8/0x2a8
mv88e6xxx_probe+0xc4c/0xf60
mdio_probe+0x78/0xb8
really_probe+0x2b8/0x5a8
__driver_probe_device+0x164/0x298
driver_probe_device+0x78/0x258
__device_attach_driver+0x274/0x350
Freed by task 42:
__kasan_slab_free+0x48/0x68
kfree+0x138/0x418
dsa_register_switch+0x2694/0x2ae0
mv88e6xxx_register_switch+0x1b8/0x2a8
mv88e6xxx_probe+0xc4c/0xf60
mdio_probe+0x78/0xb8
really_probe+0x2b8/0x5a8
__driver_probe_device+0x164/0x298
driver_probe_device+0x78/0x258
__device_attach_driver+0x274/0x350
The simplest way to fix the bug is to delete the routing table in its
entirety. dsa_tree_setup_routing_table() has no problem in regenerating
it even if we deleted links between ports other than those of switch N,
because dsa_link_touch() first checks whether the port pair already
exists in dst->rtable, allocating if not.
The deletion of the routing table in its entirety already exists in
dsa_tree_teardown(), so refactor that into a function that can also be
called from the tree setup error path.
In my analysis of the commit to blame, it is the one which added
dsa_link elements to dst->rtable. Prior to that, each switch had its own
ds->rtable which is freed when the switch fails to probe. But the tree
is potentially persistent memory.
CVSS Score
7.8
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
isofs: Prevent the use of too small fid
syzbot reported a slab-out-of-bounds Read in isofs_fh_to_parent. [1]
The handle_bytes value passed in by the reproducing program is equal to 12.
In handle_to_path(), only 12 bytes of memory are allocated for the structure
file_handle->f_handle member, which causes an out-of-bounds access when
accessing the member parent_block of the structure isofs_fid in isofs,
because accessing parent_block requires at least 16 bytes of f_handle.
Here, fh_len is used to indirectly confirm that the value of handle_bytes
is greater than 3 before accessing parent_block.
[1]
BUG: KASAN: slab-out-of-bounds in isofs_fh_to_parent+0x1b8/0x210 fs/isofs/export.c:183
Read of size 4 at addr ffff0000cc030d94 by task syz-executor215/6466
CPU: 1 UID: 0 PID: 6466 Comm: syz-executor215 Not tainted 6.14.0-rc7-syzkaller-ga2392f333575 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call trace:
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C)
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0x198/0x550 mm/kasan/report.c:521
kasan_report+0xd8/0x138 mm/kasan/report.c:634
__asan_report_load4_noabort+0x20/0x2c mm/kasan/report_generic.c:380
isofs_fh_to_parent+0x1b8/0x210 fs/isofs/export.c:183
exportfs_decode_fh_raw+0x2dc/0x608 fs/exportfs/expfs.c:523
do_handle_to_path+0xa0/0x198 fs/fhandle.c:257
handle_to_path fs/fhandle.c:385 [inline]
do_handle_open+0x8cc/0xb8c fs/fhandle.c:403
__do_sys_open_by_handle_at fs/fhandle.c:443 [inline]
__se_sys_open_by_handle_at fs/fhandle.c:434 [inline]
__arm64_sys_open_by_handle_at+0x80/0x94 fs/fhandle.c:434
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Allocated by task 6466:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x40/0x78 mm/kasan/common.c:68
kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:562
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4294 [inline]
__kmalloc_noprof+0x32c/0x54c mm/slub.c:4306
kmalloc_noprof include/linux/slab.h:905 [inline]
handle_to_path fs/fhandle.c:357 [inline]
do_handle_open+0x5a4/0xb8c fs/fhandle.c:403
__do_sys_open_by_handle_at fs/fhandle.c:443 [inline]
__se_sys_open_by_handle_at fs/fhandle.c:434 [inline]
__arm64_sys_open_by_handle_at+0x80/0x94 fs/fhandle.c:434
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
CVSS Score
7.1
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: Prevent division by zero
The user can set any speed value.
If speed is greater than UINT_MAX/8, division by zero is possible.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
virtiofs: add filesystem context source name check
In certain scenarios, for example, during fuzz testing, the source
name may be NULL, which could lead to a kernel panic. Therefore, an
extra check for the source name should be added.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
drm/nouveau: prime: fix ttm_bo_delayed_delete oops
Fix an oops in ttm_bo_delayed_delete which results from dererencing a
dangling pointer:
Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b7b: 0000 [#1] PREEMPT SMP
CPU: 4 UID: 0 PID: 1082 Comm: kworker/u65:2 Not tainted 6.14.0-rc4-00267-g505460b44513-dirty #216
Hardware name: LENOVO 82N6/LNVNB161216, BIOS GKCN65WW 01/16/2024
Workqueue: ttm ttm_bo_delayed_delete [ttm]
RIP: 0010:dma_resv_iter_first_unlocked+0x55/0x290
Code: 31 f6 48 c7 c7 00 2b fa aa e8 97 bd 52 ff e8 a2 c1 53 00 5a 85 c0 74 48 e9 88 01 00 00 4c 89 63 20 4d 85 e4 0f 84 30 01 00 00 <41> 8b 44 24 10 c6 43 2c 01 48 89 df 89 43 28 e8 97 fd ff ff 4c 8b
RSP: 0018:ffffbf9383473d60 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffbf9383473d88 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffbf9383473d78 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 6b6b6b6b6b6b6b6b
R13: ffffa003bbf78580 R14: ffffa003a6728040 R15: 00000000000383cc
FS: 0000000000000000(0000) GS:ffffa00991c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000758348024dd0 CR3: 000000012c259000 CR4: 0000000000f50ef0
PKRU: 55555554
Call Trace:
<TASK>
? __die_body.cold+0x19/0x26
? die_addr+0x3d/0x70
? exc_general_protection+0x159/0x460
? asm_exc_general_protection+0x27/0x30
? dma_resv_iter_first_unlocked+0x55/0x290
dma_resv_wait_timeout+0x56/0x100
ttm_bo_delayed_delete+0x69/0xb0 [ttm]
process_one_work+0x217/0x5c0
worker_thread+0x1c8/0x3d0
? apply_wqattrs_cleanup.part.0+0xc0/0xc0
kthread+0x10b/0x240
? kthreads_online_cpu+0x140/0x140
ret_from_fork+0x40/0x70
? kthreads_online_cpu+0x140/0x140
ret_from_fork_asm+0x11/0x20
</TASK>
The cause of this is:
- drm_prime_gem_destroy calls dma_buf_put(dma_buf) which releases the
reference to the shared dma_buf. The reference count is 0, so the
dma_buf is destroyed, which in turn decrements the corresponding
amdgpu_bo reference count to 0, and the amdgpu_bo is destroyed -
calling drm_gem_object_release then dma_resv_fini (which destroys the
reservation object), then finally freeing the amdgpu_bo.
- nouveau_bo obj->bo.base.resv is now a dangling pointer to the memory
formerly allocated to the amdgpu_bo.
- nouveau_gem_object_del calls ttm_bo_put(&nvbo->bo) which calls
ttm_bo_release, which schedules ttm_bo_delayed_delete.
- ttm_bo_delayed_delete runs and dereferences the dangling resv pointer,
resulting in a general protection fault.
Fix this by moving the drm_prime_gem_destroy call from
nouveau_gem_object_del to nouveau_bo_del_ttm. This ensures that it will
be run after ttm_bo_delayed_delete.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: Prevent division by zero
The user can set any speed value.
If speed is greater than UINT_MAX/8, division by zero is possible.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: Prevent division by zero
The user can set any speed value.
If speed is greater than UINT_MAX/8, division by zero is possible.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
net: tls: explicitly disallow disconnect
syzbot discovered that it can disconnect a TLS socket and then
run into all sort of unexpected corner cases. I have a vague
recollection of Eric pointing this out to us a long time ago.
Supporting disconnect is really hard, for one thing if offload
is enabled we'd need to wait for all packets to be _acked_.
Disconnect is not commonly used, disallow it.
The immediate problem syzbot run into is the warning in the strp,
but that's just the easiest bug to trigger:
WARNING: CPU: 0 PID: 5834 at net/tls/tls_strp.c:486 tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486
RIP: 0010:tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486
Call Trace:
<TASK>
tls_rx_rec_wait+0x280/0xa60 net/tls/tls_sw.c:1363
tls_sw_recvmsg+0x85c/0x1c30 net/tls/tls_sw.c:2043
inet6_recvmsg+0x2c9/0x730 net/ipv6/af_inet6.c:678
sock_recvmsg_nosec net/socket.c:1023 [inline]
sock_recvmsg+0x109/0x280 net/socket.c:1045
__sys_recvfrom+0x202/0x380 net/socket.c:2237
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
tipc: fix memory leak in tipc_link_xmit
In case the backlog transmit queue for system-importance messages is overloaded,
tipc_link_xmit() returns -ENOBUFS but the skb list is not purged. This leads to
memory leak and failure when a skb is allocated.
This commit fixes this issue by purging the skb list before tipc_link_xmit()
returns.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01