In the Linux kernel, the following vulnerability has been resolved:
scsi: ufs: core: Fix possible NULL pointer dereference in ufshcd_add_command_trace()
The kernel log indicates a crash in ufshcd_add_command_trace, due to a NULL
pointer dereference when accessing hwq->id. This can happen if
ufshcd_mcq_req_to_hwq() returns NULL.
This patch adds a NULL check for hwq before accessing its id field to
prevent a kernel crash.
Kernel log excerpt:
[<ffffffd5d192dc4c>] notify_die+0x4c/0x8c
[<ffffffd5d1814e58>] __die+0x60/0xb0
[<ffffffd5d1814d64>] die+0x4c/0xe0
[<ffffffd5d181575c>] die_kernel_fault+0x74/0x88
[<ffffffd5d1864db4>] __do_kernel_fault+0x314/0x318
[<ffffffd5d2a3cdf8>] do_page_fault+0xa4/0x5f8
[<ffffffd5d2a3cd34>] do_translation_fault+0x34/0x54
[<ffffffd5d1864524>] do_mem_abort+0x50/0xa8
[<ffffffd5d2a297dc>] el1_abort+0x3c/0x64
[<ffffffd5d2a29718>] el1h_64_sync_handler+0x44/0xcc
[<ffffffd5d181133c>] el1h_64_sync+0x80/0x88
[<ffffffd5d255c1dc>] ufshcd_add_command_trace+0x23c/0x320
[<ffffffd5d255bad8>] ufshcd_compl_one_cqe+0xa4/0x404
[<ffffffd5d2572968>] ufshcd_mcq_poll_cqe_lock+0xac/0x104
[<ffffffd5d11c7460>] ufs_mtk_mcq_intr+0x54/0x74 [ufs_mediatek_mod]
[<ffffffd5d19ab92c>] __handle_irq_event_percpu+0xc8/0x348
[<ffffffd5d19abca8>] handle_irq_event+0x3c/0xa8
[<ffffffd5d19b1f0c>] handle_fasteoi_irq+0xf8/0x294
[<ffffffd5d19aa778>] generic_handle_domain_irq+0x54/0x80
[<ffffffd5d18102bc>] gic_handle_irq+0x1d4/0x330
[<ffffffd5d1838210>] call_on_irq_stack+0x44/0x68
[<ffffffd5d183af30>] do_interrupt_handler+0x78/0xd8
[<ffffffd5d2a29c00>] el1_interrupt+0x48/0xa8
[<ffffffd5d2a29ba8>] el1h_64_irq_handler+0x14/0x24
[<ffffffd5d18113c4>] el1h_64_irq+0x80/0x88
[<ffffffd5d2527fb4>] arch_local_irq_enable+0x4/0x1c
[<ffffffd5d25282e4>] cpuidle_enter+0x34/0x54
[<ffffffd5d195a678>] do_idle+0x1dc/0x2f8
[<ffffffd5d195a7c4>] cpu_startup_entry+0x30/0x3c
[<ffffffd5d18155c4>] secondary_start_kernel+0x134/0x1ac
[<ffffffd5d18640bc>] __secondary_switched+0xc4/0xcc
In the Linux kernel, the following vulnerability has been resolved:
unshare: fix unshare_fs() handling
There's an unpleasant corner case in unshare(2), when we have a
CLONE_NEWNS in flags and current->fs hadn't been shared at all; in that
case copy_mnt_ns() gets passed current->fs instead of a private copy,
which causes interesting warts in proof of correctness]
> I guess if private means fs->users == 1, the condition could still be true.
Unfortunately, it's worse than just a convoluted proof of correctness.
Consider the case when we have CLONE_NEWCGROUP in addition to CLONE_NEWNS
(and current->fs->users == 1).
We pass current->fs to copy_mnt_ns(), all right. Suppose it succeeds and
flips current->fs->{pwd,root} to corresponding locations in the new namespace.
Now we proceed to copy_cgroup_ns(), which fails (e.g. with -ENOMEM).
We call put_mnt_ns() on the namespace created by copy_mnt_ns(), it's
destroyed and its mount tree is dissolved, but... current->fs->root and
current->fs->pwd are both left pointing to now detached mounts.
They are pinning those, so it's not a UAF, but it leaves the calling
process with unshare(2) failing with -ENOMEM _and_ leaving it with
pwd and root on detached isolated mounts. The last part is clearly a bug.
There is other fun related to that mess (races with pivot_root(), including
the one between pivot_root() and fork(), of all things), but this one
is easy to isolate and fix - treat CLONE_NEWNS as "allocate a new
fs_struct even if it hadn't been shared in the first place". Sure, we could
go for something like "if both CLONE_NEWNS *and* one of the things that might
end up failing after copy_mnt_ns() call in create_new_namespaces() are set,
force allocation of new fs_struct", but let's keep it simple - the cost
of copy_fs_struct() is trivial.
Another benefit is that copy_mnt_ns() with CLONE_NEWNS *always* gets
a freshly allocated fs_struct, yet to be attached to anything. That
seriously simplifies the analysis...
FWIW, that bug had been there since the introduction of unshare(2) ;-/
In the Linux kernel, the following vulnerability has been resolved:
scsi: mpi3mr: Add NULL checks when resetting request and reply queues
The driver encountered a crash during resource cleanup when the reply and
request queues were NULL due to freed memory. This issue occurred when the
creation of reply or request queues failed, and the driver freed the memory
first, but attempted to mem set the content of the freed memory, leading to
a system crash.
Add NULL pointer checks for reply and request queues before accessing the
reply/request memory during cleanup
In the Linux kernel, the following vulnerability has been resolved:
fs: init flags_valid before calling vfs_fileattr_get
syzbot reported a uninit-value bug in [1].
Similar to the "*get" context where the kernel's internal file_kattr
structure is initialized before calling vfs_fileattr_get(), we should
use the same mechanism when using fa.
[1]
BUG: KMSAN: uninit-value in fuse_fileattr_get+0xeb4/0x1450 fs/fuse/ioctl.c:517
fuse_fileattr_get+0xeb4/0x1450 fs/fuse/ioctl.c:517
vfs_fileattr_get fs/file_attr.c:94 [inline]
__do_sys_file_getattr fs/file_attr.c:416 [inline]
Local variable fa.i created at:
__do_sys_file_getattr fs/file_attr.c:380 [inline]
__se_sys_file_getattr+0x8c/0xbd0 fs/file_attr.c:372
In the Linux kernel, the following vulnerability has been resolved:
net: spacemit: Fix error handling in emac_tx_mem_map()
The DMA mappings were leaked on mapping error. Free them with the
existing emac_free_tx_buf() function.
In the Linux kernel, the following vulnerability has been resolved:
rxrpc, afs: Fix missing error pointer check after rxrpc_kernel_lookup_peer()
rxrpc_kernel_lookup_peer() can also return error pointers in addition to
NULL, so just checking for NULL is not sufficient.
Fix this by:
(1) Changing rxrpc_kernel_lookup_peer() to return -ENOMEM rather than NULL
on allocation failure.
(2) Making the callers in afs use IS_ERR() and PTR_ERR() to pass on the
error code returned.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: RX, Fix XDP multi-buf frag counting for legacy RQ
XDP multi-buf programs can modify the layout of the XDP buffer when the
program calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The
referenced commit in the fixes tag corrected the assumption in the mlx5
driver that the XDP buffer layout doesn't change during a program
execution. However, this fix introduced another issue: the dropped
fragments still need to be counted on the driver side to avoid page
fragment reference counting issues.
Such issue can be observed with the
test_xdp_native_adjst_tail_shrnk_data selftest when using a payload of
3600 and shrinking by 256 bytes (an upcoming selftest patch): the last
fragment gets released by the XDP code but doesn't get tracked by the
driver. This results in a negative pp_ref_count during page release and
the following splat:
WARNING: include/net/page_pool/helpers.h:297 at mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core], CPU#12: ip/3137
Modules linked in: [...]
CPU: 12 UID: 0 PID: 3137 Comm: ip Not tainted 6.19.0-rc3+ #12 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core]
[...]
Call Trace:
<TASK>
mlx5e_dealloc_rx_wqe+0xcb/0x1a0 [mlx5_core]
mlx5e_free_rx_descs+0x7f/0x110 [mlx5_core]
mlx5e_close_rq+0x50/0x60 [mlx5_core]
mlx5e_close_queues+0x36/0x2c0 [mlx5_core]
mlx5e_close_channel+0x1c/0x50 [mlx5_core]
mlx5e_close_channels+0x45/0x80 [mlx5_core]
mlx5e_safe_switch_params+0x1a5/0x230 [mlx5_core]
mlx5e_change_mtu+0xf3/0x2f0 [mlx5_core]
netif_set_mtu_ext+0xf1/0x230
do_setlink.isra.0+0x219/0x1180
rtnl_newlink+0x79f/0xb60
rtnetlink_rcv_msg+0x213/0x3a0
netlink_rcv_skb+0x48/0xf0
netlink_unicast+0x24a/0x350
netlink_sendmsg+0x1ee/0x410
__sock_sendmsg+0x38/0x60
____sys_sendmsg+0x232/0x280
___sys_sendmsg+0x78/0xb0
__sys_sendmsg+0x5f/0xb0
[...]
do_syscall_64+0x57/0xc50
This patch fixes the issue by doing page frag counting on all the
original XDP buffer fragments for all relevant XDP actions (XDP_TX ,
XDP_REDIRECT and XDP_PASS). This is basically reverting to the original
counting before the commit in the fixes tag.
As frag_page is still pointing to the original tail, the nr_frags
parameter to xdp_update_skb_frags_info() needs to be calculated
in a different way to reflect the new nr_frags.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: RX, Fix XDP multi-buf frag counting for striding RQ
XDP multi-buf programs can modify the layout of the XDP buffer when the
program calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The
referenced commit in the fixes tag corrected the assumption in the mlx5
driver that the XDP buffer layout doesn't change during a program
execution. However, this fix introduced another issue: the dropped
fragments still need to be counted on the driver side to avoid page
fragment reference counting issues.
The issue was discovered by the drivers/net/xdp.py selftest,
more specifically the test_xdp_native_tx_mb:
- The mlx5 driver allocates a page_pool page and initializes it with
a frag counter of 64 (pp_ref_count=64) and the internal frag counter
to 0.
- The test sends one packet with no payload.
- On RX (mlx5e_skb_from_cqe_mpwrq_nonlinear()), mlx5 configures the XDP
buffer with the packet data starting in the first fragment which is the
page mentioned above.
- The XDP program runs and calls bpf_xdp_pull_data() which moves the
header into the linear part of the XDP buffer. As the packet doesn't
contain more data, the program drops the tail fragment since it no
longer contains any payload (pp_ref_count=63).
- mlx5 device skips counting this fragment. Internal frag counter
remains 0.
- mlx5 releases all 64 fragments of the page but page pp_ref_count is
63 => negative reference counting error.
Resulting splat during the test:
WARNING: CPU: 0 PID: 188225 at ./include/net/page_pool/helpers.h:297 mlx5e_page_release_fragmented.isra.0+0xbd/0xe0 [mlx5_core]
Modules linked in: [...]
CPU: 0 UID: 0 PID: 188225 Comm: ip Not tainted 6.18.0-rc7_for_upstream_min_debug_2025_12_08_11_44 #1 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:mlx5e_page_release_fragmented.isra.0+0xbd/0xe0 [mlx5_core]
[...]
Call Trace:
<TASK>
mlx5e_free_rx_mpwqe+0x20a/0x250 [mlx5_core]
mlx5e_dealloc_rx_mpwqe+0x37/0xb0 [mlx5_core]
mlx5e_free_rx_descs+0x11a/0x170 [mlx5_core]
mlx5e_close_rq+0x78/0xa0 [mlx5_core]
mlx5e_close_queues+0x46/0x2a0 [mlx5_core]
mlx5e_close_channel+0x24/0x90 [mlx5_core]
mlx5e_close_channels+0x5d/0xf0 [mlx5_core]
mlx5e_safe_switch_params+0x2ec/0x380 [mlx5_core]
mlx5e_change_mtu+0x11d/0x490 [mlx5_core]
mlx5e_change_nic_mtu+0x19/0x30 [mlx5_core]
netif_set_mtu_ext+0xfc/0x240
do_setlink.isra.0+0x226/0x1100
rtnl_newlink+0x7a9/0xba0
rtnetlink_rcv_msg+0x220/0x3c0
netlink_rcv_skb+0x4b/0xf0
netlink_unicast+0x255/0x380
netlink_sendmsg+0x1f3/0x420
__sock_sendmsg+0x38/0x60
____sys_sendmsg+0x1e8/0x240
___sys_sendmsg+0x7c/0xb0
[...]
__sys_sendmsg+0x5f/0xb0
do_syscall_64+0x55/0xc70
The problem applies for XDP_PASS as well which is handled in a different
code path in the driver.
This patch fixes the issue by doing page frag counting on all the
original XDP buffer fragments for all relevant XDP actions (XDP_TX ,
XDP_REDIRECT and XDP_PASS). This is basically reverting to the original
counting before the commit in the fixes tag.
As frag_page is still pointing to the original tail, the nr_frags
parameter to xdp_update_skb_frags_info() needs to be calculated
in a different way to reflect the new nr_frags.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix DMA FIFO desync on error CQE SQ recovery
In case of a TX error CQE, a recovery flow is triggered,
mlx5e_reset_txqsq_cc_pc() resets dma_fifo_cc to 0 but not dma_fifo_pc,
desyncing the DMA FIFO producer and consumer.
After recovery, the producer pushes new DMA entries at the old
dma_fifo_pc, while the consumer reads from position 0.
This causes us to unmap stale DMA addresses from before the recovery.
The DMA FIFO is a purely software construct with no HW counterpart.
At the point of reset, all WQEs have been flushed so dma_fifo_cc is
already equal to dma_fifo_pc. There is no need to reset either counter,
similar to how skb_fifo pc/cc are untouched.
Remove the 'dma_fifo_cc = 0' reset.
This fixes the following WARNING:
WARNING: CPU: 0 PID: 0 at drivers/iommu/dma-iommu.c:1240 iommu_dma_unmap_page+0x79/0x90
Modules linked in: mlx5_vdpa vringh vdpa bonding mlx5_ib mlx5_vfio_pci ipip mlx5_fwctl tunnel4 mlx5_core ib_ipoib geneve ip6_gre ip_gre gre nf_tables ip6_tunnel rdma_ucm ib_uverbs ib_umad vfio_pci vfio_pci_core act_mirred act_skbedit act_vlan vhost_net vhost tap ip6table_mangle ip6table_nat ip6table_filter ip6_tables iptable_mangle cls_matchall nfnetlink_cttimeout act_gact cls_flower sch_ingress vhost_iotlb iptable_raw tunnel6 vfio_iommu_type1 vfio openvswitch nsh rpcsec_gss_krb5 auth_rpcgss oid_registry xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat nf_nat xt_addrtype br_netfilter overlay zram zsmalloc rpcrdma ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm ib_core fuse [last unloaded: nf_tables]
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-rc5_for_upstream_min_debug_2024_12_30_21_33 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:iommu_dma_unmap_page+0x79/0x90
Code: 2b 4d 3b 21 72 26 4d 3b 61 08 73 20 49 89 d8 44 89 f9 5b 4c 89 f2 4c 89 e6 48 89 ef 5d 41 5c 41 5d 41 5e 41 5f e9 c7 ae 9e ff <0f> 0b 5b 5d 41 5c 41 5d 41 5e 41 5f c3 66 2e 0f 1f 84 00 00 00 00
Call Trace:
<IRQ>
? __warn+0x7d/0x110
? iommu_dma_unmap_page+0x79/0x90
? report_bug+0x16d/0x180
? handle_bug+0x4f/0x90
? exc_invalid_op+0x14/0x70
? asm_exc_invalid_op+0x16/0x20
? iommu_dma_unmap_page+0x79/0x90
? iommu_dma_unmap_page+0x2e/0x90
dma_unmap_page_attrs+0x10d/0x1b0
mlx5e_tx_wi_dma_unmap+0xbe/0x120 [mlx5_core]
mlx5e_poll_tx_cq+0x16d/0x690 [mlx5_core]
mlx5e_napi_poll+0x8b/0xac0 [mlx5_core]
__napi_poll+0x24/0x190
net_rx_action+0x32a/0x3b0
? mlx5_eq_comp_int+0x7e/0x270 [mlx5_core]
? notifier_call_chain+0x35/0xa0
handle_softirqs+0xc9/0x270
irq_exit_rcu+0x71/0xd0
common_interrupt+0x7f/0xa0
</IRQ>
<TASK>
asm_common_interrupt+0x22/0x40