Debian: Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
nfsd: decrease sc_count directly if fail to queue dl_recall
A deadlock warning occurred when invoking nfs4_put_stid following a failed
dl_recall queue operation:
T1 T2
nfs4_laundromat
nfs4_get_client_reaplist
nfs4_anylock_blockers
__break_lease
spin_lock // ctx->flc_lock
spin_lock // clp->cl_lock
nfs4_lockowner_has_blockers
locks_owner_has_blockers
spin_lock // flctx->flc_lock
nfsd_break_deleg_cb
nfsd_break_one_deleg
nfs4_put_stid
refcount_dec_and_lock
spin_lock // clp->cl_lock
When a file is opened, an nfs4_delegation is allocated with sc_count
initialized to 1, and the file_lease holds a reference to the delegation.
The file_lease is then associated with the file through kernel_setlease.
The disassociation is performed in nfsd4_delegreturn via the following
call chain:
nfsd4_delegreturn --> destroy_delegation --> destroy_unhashed_deleg -->
nfs4_unlock_deleg_lease --> kernel_setlease --> generic_delete_lease
The corresponding sc_count reference will be released after this
disassociation.
Since nfsd_break_one_deleg executes while holding the flc_lock, the
disassociation process becomes blocked when attempting to acquire flc_lock
in generic_delete_lease. This means:
1) sc_count in nfsd_break_one_deleg will not be decremented to 0;
2) The nfs4_put_stid called by nfsd_break_one_deleg will not attempt to
acquire cl_lock;
3) Consequently, no deadlock condition is created.
Given that sc_count in nfsd_break_one_deleg remains non-zero, we can
safely perform refcount_dec on sc_count directly. This approach
effectively avoids triggering deadlock warnings.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
igc: fix PTM cycle trigger logic
Writing to clear the PTM status 'valid' bit while the PTM cycle is
triggered results in unreliable PTM operation. To fix this, clear the
PTM 'trigger' and status after each PTM transaction.
The issue can be reproduced with the following:
$ sudo phc2sys -R 1000 -O 0 -i tsn0 -m
Note: 1000 Hz (-R 1000) is unrealistically large, but provides a way to
quickly reproduce the issue.
PHC2SYS exits with:
"ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction
fails
This patch also fixes a hang in igc_probe() when loading the igc
driver in the kdump kernel on systems supporting PTM.
The igc driver running in the base kernel enables PTM trigger in
igc_probe(). Therefore the driver is always in PTM trigger mode,
except in brief periods when manually triggering a PTM cycle.
When a crash occurs, the NIC is reset while PTM trigger is enabled.
Due to a hardware problem, the NIC is subsequently in a bad busmaster
state and doesn't handle register reads/writes. When running
igc_probe() in the kdump kernel, the first register access to a NIC
register hangs driver probing and ultimately breaks kdump.
With this patch, igc has PTM trigger disabled most of the time,
and the trigger is only enabled for very brief (10 - 100 us) periods
when manually triggering a PTM cycle. Chances that a crash occurs
during a PTM trigger are not 0, but extremely reduced.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
HID: pidff: Fix null pointer dereference in pidff_find_fields
This function triggered a null pointer dereference if used to search for
a report that isn't implemented on the device. This happened both for
optional and required reports alike.
The same logic was applied to pidff_find_special_field and although
pidff_init_fields should return an error earlier if one of the required
reports is missing, future modifications could change this logic and
resurface this possible null pointer dereference again.
LKML bug report:
https://lore.kernel.org/all/CAL-gK7f5=R0nrrQdPtaZZr1fd-cdAMbDMuZ_NLA8vM0SX+nGSw@mail.gmail.com
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: mv88e6xxx: fix -ENOENT when deleting VLANs and MST is unsupported
Russell King reports that on the ZII dev rev B, deleting a bridge VLAN
from a user port fails with -ENOENT:
https://lore.kernel.org/netdev/Z_lQXNP0s5-IiJzd@shell.armlinux.org.uk/
This comes from mv88e6xxx_port_vlan_leave() -> mv88e6xxx_mst_put(),
which tries to find an MST entry in &chip->msts associated with the SID,
but fails and returns -ENOENT as such.
But we know that this chip does not support MST at all, so that is not
surprising. The question is why does the guard in mv88e6xxx_mst_put()
not exit early:
if (!sid)
return 0;
And the answer seems to be simple: the sid comes from vlan.sid which
supposedly was previously populated by mv88e6xxx_vtu_get().
But some chip->info->ops->vtu_getnext() implementations do not populate
vlan.sid, for example see mv88e6185_g1_vtu_getnext(). In that case,
later in mv88e6xxx_port_vlan_leave() we are using a garbage sid which is
just residual stack memory.
Testing for sid == 0 covers all cases of a non-bridge VLAN or a bridge
VLAN mapped to the default MSTI. For some chips, SID 0 is valid and
installed by mv88e6xxx_stu_setup(). A chip which does not support the
STU would implicitly only support mapping all VLANs to the default MSTI,
so although SID 0 is not valid, it would be sufficient, if we were to
zero-initialize the vlan structure, to fix the bug, due to the
coincidence that a test for vlan.sid == 0 already exists and leads to
the same (correct) behavior.
Another option which would be sufficient would be to add a test for
mv88e6xxx_has_stu() inside mv88e6xxx_mst_put(), symmetric to the one
which already exists in mv88e6xxx_mst_get(). But that placement means
the caller will have to dereference vlan.sid, which means it will access
uninitialized memory, which is not nice even if it ignores it later.
So we end up making both modifications, in order to not rely just on the
sid == 0 coincidence, but also to avoid having uninitialized structure
fields which might get temporarily accessed.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
RDMA/core: Silence oversized kvmalloc() warning
syzkaller triggered an oversized kvmalloc() warning.
Silence it by adding __GFP_NOWARN.
syzkaller log:
WARNING: CPU: 7 PID: 518 at mm/util.c:665 __kvmalloc_node_noprof+0x175/0x180
CPU: 7 UID: 0 PID: 518 Comm: c_repro Not tainted 6.11.0-rc6+ #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:__kvmalloc_node_noprof+0x175/0x180
RSP: 0018:ffffc90001e67c10 EFLAGS: 00010246
RAX: 0000000000000100 RBX: 0000000000000400 RCX: ffffffff8149d46b
RDX: 0000000000000000 RSI: ffff8881030fae80 RDI: 0000000000000002
RBP: 000000712c800000 R08: 0000000000000100 R09: 0000000000000000
R10: ffffc90001e67c10 R11: 0030ae0601000000 R12: 0000000000000000
R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000
FS: 00007fde79159740(0000) GS:ffff88813bdc0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000180 CR3: 0000000105eb4005 CR4: 00000000003706b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ib_umem_odp_get+0x1f6/0x390
mlx5_ib_reg_user_mr+0x1e8/0x450
ib_uverbs_reg_mr+0x28b/0x440
ib_uverbs_write+0x7d3/0xa30
vfs_write+0x1ac/0x6c0
ksys_write+0x134/0x170
? __sanitizer_cov_trace_pc+0x1c/0x50
do_syscall_64+0x50/0x110
entry_SYSCALL_64_after_hwframe+0x76/0x7e
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
fbdev: omapfb: Add 'plane' value check
Function dispc_ovl_setup is not intended to work with the value OMAP_DSS_WB
of the enum parameter plane.
The value of this parameter is initialized in dss_init_overlays and in the
current state of the code it cannot take this value so it's not a real
problem.
For the purposes of defensive coding it wouldn't be superfluous to check
the parameter value, because some functions down the call stack process
this value correctly and some not.
For example, in dispc_ovl_setup_global_alpha it may lead to buffer
overflow.
Add check for this value.
Found by Linux Verification Center (linuxtesting.org) with SVACE static
analysis tool.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: handle amdgpu_cgs_create_device() errors in amd_powerplay_create()
Add error handling to propagate amdgpu_cgs_create_device() failures
to the caller. When amdgpu_cgs_create_device() fails, release hwmgr
and return -ENOMEM to prevent null pointer dereference.
[v1]->[v2]: Change error code from -EINVAL to -ENOMEM. Free hwmgr.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Fix mode1 reset crash issue
If HW scheduler hangs and mode1 reset is used to recover GPU, KFD signal
user space to abort the processes. After process abort exit, user queues
still use the GPU to access system memory before h/w is reset while KFD
cleanup worker free system memory and free VRAM.
There is use-after-free race bug that KFD allocate and reuse the freed
system memory, and user queue write to the same system memory to corrupt
the data structure and cause driver crash.
To fix this race, KFD cleanup worker terminate user queues, then flush
reset_domain wq to wait for any GPU ongoing reset complete, and then
free outstanding BOs.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
scsi: st: Fix array overflow in st_setup()
Change the array size to follow parms size instead of a fixed value.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
fs/jfs: Prevent integer overflow in AG size calculation
The JFS filesystem calculates allocation group (AG) size using 1 <<
l2agsize in dbExtendFS(). When l2agsize exceeds 31 (possible with >2TB
aggregates on 32-bit systems), this 32-bit shift operation causes undefined
behavior and improper AG sizing.
On 32-bit architectures:
- Left-shifting 1 by 32+ bits results in 0 due to integer overflow
- This creates invalid AG sizes (0 or garbage values) in
sbi->bmap->db_agsize
- Subsequent block allocations would reference invalid AG structures
- Could lead to:
- Filesystem corruption during extend operations
- Kernel crashes due to invalid memory accesses
- Security vulnerabilities via malformed on-disk structures
Fix by casting to s64 before shifting:
bmp->db_agsize = (s64)1 << l2agsize;
This ensures 64-bit arithmetic even on 32-bit architectures. The cast
matches the data type of db_agsize (s64) and follows similar patterns in
JFS block calculation code.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09