| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
firewire: ohci: fix NULL pointer dereference in ar_context_release
During the error handling path of the driver's probe function, a NULL
pointer dereference can occur in ar_context_release().
When pci_probe() fails early (e.g., if pcim_enable_device() or MMIO mapping
fails), the devres cleanup mechanism invokes release_ohci(). This function
unconditionally calls ar_context_release() to clean up the asynchronous
receive contexts. However, if ar_context_init() was not yet called,
ctx->ohci remains NULL (as the fw_ohci structure is zero-initialized by
devres_alloc()).
ar_context_release() immediately dereferences ctx->ohci to get the dev
pointer before checking if the context was actually initialized, leading to
a crash:
Oops: general protection fault, probably for non-canonical address
0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
RIP: 0010:ar_context_release+0x3f/0x380 drivers/firewire/ohci.c:543
Call Trace:
release_ohci+0x3f/0x60 drivers/firewire/ohci.c:3567
release_nodes drivers/base/devres.c:546 [inline]
devres_release_all+0x1a8/0x260 drivers/base/devres.c:576
device_unbind_cleanup drivers/base/dd.c:597 [inline]
really_probe+0x451/0xae0 drivers/base/dd.c:772
To fix this, move the assignment of the dev pointer after the !ctx->buffer
check. If ctx->buffer is NULL, it indicates that the context was never
successfully initialized and there is nothing to release, safely avoiding
the dereference of the uninitialized ctx->ohci pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
xfs: handle NULL b_addr in xfs_buf_free
When xfs_buf_alloc_backing_mem() fails, xfs_buf_free() is called with
bp->b_addr still NULL. The code falls through to the folio_put path
which calls virt_to_folio(NULL), dereferencing an invalid address and
causing a kernel crash.
Call Trace:
xfs_buf_free+0x25f/0x510
xfs_buf_alloc+0xc98/0x19b0
xfs_buf_find_insert+0x55/0x14d0
xfs_buf_get_map+0x122b/0x17c0
xfbtree_init_leaf_block+0x11c/0x4a0
xfbtree_init+0x1bb/0x460
xrep_rmap_setup_scan+0x100/0x1f0
xrep_rmapbt+0x41/0xc0
Fix this by skipping folio_put() when bp->b_addr is NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix netns reference imbalance in conntrack kfuncs
The opts argument of the BPF conntrack kfuncs can point to a shared
map value. __bpf_nf_ct_lookup() and __bpf_nf_ct_alloc_entry() read
opts->netns_id separately when acquiring and releasing the network
namespace reference.
The reference imbalance can occur as follows:
CPU 0 CPU 1
read opts->netns_id (-1)
skip get_net_ns_by_id()
write opts->netns_id (id)
read opts->netns_id (id)
put_net(net) /* no matching get */
The reverse transition leaks the reference. Repeating the unmatched put
can destroy a live namespace and crash later users.
The kernel reported:
Oops: general protection fault, probably for non-canonical address
KASAN: null-ptr-deref in range [0x00000000000000e8-0x00000000000000ef]
RIP: 0010:bpf_prog_test_run_xdp+0x52c/0x1700
Call Trace:
__sys_bpf+0x1662/0x50c0
__x64_sys_bpf+0x73/0xb0
do_syscall_64+0xf9/0x540
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Kernel panic - not syncing: Fatal exception
Snapshot every input field of opts with READ_ONCE() before validating or
using it. The netns_id snapshot keeps the namespace get/put pair
balanced, while the other snapshots keep the remaining options from
changing partway through an invocation. The individual reads can still
observe an inconsistent combination during a concurrent update, but each
selected field value remains stable for that invocation. |
| In the Linux kernel, the following vulnerability has been resolved:
net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()
The commit 4f61f133f354 ("net: tap: NULL pointer derefence in
dev_parse_header_protocol when skb->dev is null") fixed a crash in
tap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb().
This is required because virtio_net_hdr_to_skb() may invoke
dev_parse_header_protocol(), which dereferences skb->dev. Without the
assignment, a NULL pointer dereference can occur.
However, tap_get_user_xdp() still parses the virtio-net header before
assigning skb->dev. When the vhost TX path passes an XDP buffer containing
a GSO virtio-net header but the protocol is set to zero on purpose,
tun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev
is still NULL, resulting in a crash.
Fix this by looking up the tap device and assigning skb->dev before calling
tun_vnet_hdr_to_skb(), matching the ordering already used in
tap_get_user(). Preserve the existing RCU read-side critical section across
dev_queue_xmit(). |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: skip global block reserve accounting for rescue mounts
[BUG]
Mounting with rescue=ibadroots after corrupting the block group tree
root triggers a NULL pointer dereference:
BUG: kernel NULL pointer dereference, address: 0000000000000100
RIP: 0010:btrfs_update_global_block_rsv+0x9d/0x1c0 [btrfs]
Call Trace:
fill_dummy_bgs+0xd4/0x120 [btrfs]
open_ctree+0xc6e/0x1ca0 [btrfs]
btrfs_get_tree+0x50d/0xa40 [btrfs]
The same crash occurs with a corrupted raid stripe tree root, via
btrfs_read_block_groups() instead of fill_dummy_bgs().
[CAUSE]
With rescue=ibadroots, btrfs_read_roots() allows the mount to continue
when either root cannot be read, leaving the corresponding root pointer
NULL while its on-disk feature bit remains set.
btrfs_update_global_block_rsv() then dereferences the missing root based
on the feature bit alone.
[FIX]
Rescue mounts are fully read-only and cannot start transactions, so the
global reserve is never consumed. Under btrfs_is_full_ro(), mark the
reserve as full and return before performing the accounting.
And since we need to check if the fs is mount fully RO, export
fs_is_full_ro() as btrfs_is_full_ro(), and move it to fs.h.
[ Squash the fs_is_full_ro() export commit into this one. ] |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: cancel SSR work items during PCI shutdown
A reboot can crash the kernel if it overlaps with WLAN firmware crash
recovery (SSR). The crash is a NULL pointer dereference in the MHI teardown
path while freeing DMA-backed MHI contexts.
Simplified trace:
dma_free_attrs
mhi_deinit_dev_ctxt [mhi]
ath11k_pci_power_down [ath11k_pci]
ath11k_pci_shutdown [ath11k_pci]
device_shutdown
kernel_restart
On the host side, SSR is driven by the MHI RDDM callback, which queues
reset_work to perform device recovery. reset_work power-cycles the device
by calling ath11k_hif_power_down() followed by ath11k_hif_power_up(). The
power-down phase deinitializes MHI and frees DMA resources.
Shutdown/reboot runs fully asynchronously with this RDDM-driven SSR
recovery flow. As a result, the shutdown path
(ath11k_pci_shutdown() -> ath11k_pci_power_down()) can race with the SSR
recovery sequence.
Fix this by canceling SSR-related work items during PCI shutdown, marking
the device as unregistering, and serializing the RDDM callback path that
checks and queues reset_work. This ensures that no new SSR recovery work
can be queued once teardown has started, and that any in-flight recovery
work is fully synchronized before device power-down, preventing MHI
teardown and DMA resource freeing from running more than once.
Note: This issue only affects PCI/MHI-based devices. AHB-based ath11k
devices do not queue reset_work in normal SSR flows.
Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-04866.5-QCAHSPSWPL_V1_V2_SILICONZ_IOE-1 |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix publication race for priv->channel_stats[]
mlx5e_channel_stats_alloc() publishes a new entry to
priv->channel_stats[] and then increments priv->stats_nch as a
publication token, but neither store carries any memory barrier:
priv->channel_stats[ix] = kvzalloc_node(...);
if (!priv->channel_stats[ix])
return -ENOMEM;
priv->stats_nch++;
Concurrent readers compute the loop bound from priv->stats_nch and
then dereference priv->channel_stats[i] using plain accesses, e.g.
for (i = 0; i < priv->stats_nch; i++) {
struct mlx5e_channel_stats *cs = priv->channel_stats[i];
... cs->rq.packets ...
}
On weakly-ordered architectures (ARM, PowerPC, RISC-V) the writes to
channel_stats[ix] and stats_nch may become visible to other CPUs out
of program order. A reader can observe stats_nch == N while still
seeing channel_stats[N-1] == NULL, leading to a NULL pointer
dereference in the channel_stats loop.
This has been observed in production on BlueField-3 DPUs (arm64),
where ovs-vswitchd queries netdev statistics over netlink during NIC
bringup, racing mlx5e_open_channel() -> mlx5e_channel_stats_alloc()
on another CPU:
Unable to handle kernel NULL pointer dereference at virtual address 0x840
Hardware name: BlueField-3 DPU
pc : mlx5e_fold_sw_stats64+0x30/0x180 [mlx5_core]
Call trace:
mlx5e_fold_sw_stats64+0x30/0x180 [mlx5_core]
dev_get_stats+0x50/0xc0
ovs_vport_get_stats+0x38/0xac [openvswitch]
ovs_vport_cmd_fill_info+0x194/0x290 [openvswitch]
ovs_vport_cmd_get+0xbc/0x10c [openvswitch]
genl_family_rcv_msg_doit+0xd0/0x160
genl_rcv_msg+0xec/0x1f0
netlink_rcv_skb+0x64/0x130
genl_rcv+0x40/0x60
netlink_unicast+0x2fc/0x370
netlink_sendmsg+0x1dc/0x454
...
__arm64_sys_sendmsg+0x2c/0x40
Add mlx5e_stats_nch_write() and mlx5e_stats_nch_read() helpers in en.h
that wrap the smp_store_release()/smp_load_acquire() pair on stats_nch.
The release/acquire pair establishes the contract:
stats_nch == N => channel_stats[0..N-1] are visible and non-NULL.
Publish the stats_nch increment via mlx5e_stats_nch_write() in the
writer (mlx5e_channel_stats_alloc()), and read stats_nch via
mlx5e_stats_nch_read() in all readers: mlx5e RX/TX queue stats,
mlx5e_get_base_stats(), ethtool channels stats, IPoIB stats, the
sw_stats fold and the HV VHCA stats agent. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: Handle TC_ACT_REDIRECT from qdisc filter chains
When a TC filter attached to a qdisc filter chain returns
TC_ACT_REDIRECT (ex: via an eBPF program calling bpf_redirect() or an
act_bpf action), the redirect was silently lost i.e no qdisc classify
function handled TC_ACT_REDIRECT, so the packet fell through the
switch and was enqueued normally instead of being redirected.
This has been broken since bpf_redirect() was introduced for TC in
commit 27b29f63058d ("bpf: add bpf_redirect() helper"). We got lucky
for a long time because bpf_net_context was a per-CPU variable that
was always available.
commit 401cb7dae813 ("net: Reference bpf_redirect_info via task_struct
on PREEMPT_RT.") turned bpf_net_context into a task_struct member that
is only set up by explicit callers. Without a caller setting it up,
bpf_redirect() itself crashes with a NULL pointer dereference in
bpf_net_ctx_get_ri(). However, even with bpf_net_context available,
TC_ACT_REDIRECT from qdisc filter chains cannot be honored without
adding skb_do_redirect() calls to every qdisc classify function, which
would require changes across net/sched/. Isolate it to ebpf core where
it belongs.
Instead, add a tcf_classify_qdisc() inline helper in pkt_cls.h, as a
wrapper around tcf_classify() for use by qdisc classify functions and
tcf_qevent_handle(). When the classify verdict is TC_ACT_REDIRECT,
the wrapper converts it to TC_ACT_SHOT, dropping the packet rather
than letting it continue silently. Dropping is preferred over
letting the packet through because the user immediately sees packet
loss. Silently passing the packet through would hide the problem and
leave the user wondering why their redirect is not working.
The clsact fast path, tc_run() continues to call tcf_classify() directly
and is unaffected: TC_ACT_REDIRECT is returned as-is and handled by
sch_handle_egress/ingress() calling skb_do_redirect() as before. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/irdma: Prevent user-triggered null deref on QP create
Previously, the user QP creation path would only attempt to
populate iwqp->iwpbl if the user-provided req.user_wqe_bufs
field was non-zero. The problem is that iwqp->iwpbl is
unconditionally dereferenced later on in irdma_setup_virt_qp.
While there was a check for iwqp->iwpbl != NULL, this check
would only occur if req.user_wqe_bufs was non-zero. The end
result is that a user could send a zero user_wqe_bufs value
and trigger a null ptr deref.
Fix this by unconditionally calling irdma_get_pbl and bailing
if it fails, similar to the CQ and SRQ paths. |
| In the Linux kernel, the following vulnerability has been resolved:
bnxt_en: Handle partially initialized auxiliary devices
bnxt_aux_devices_init() calls auxiliary_device_init() before all fields
used by bnxt_aux_dev_release() are initialized. After
auxiliary_device_init() succeeds, later errors must unwind with
auxiliary_device_uninit(), which invokes the release callback.
The release callback assumes that aux_priv->id, aux_priv->edev,
edev->net and edev->ulp_tbl are all populated. If allocation fails
after auxiliary_device_init(), the release path can otherwise dereference
or clear partially initialized state.
Allocate and attach the bnxt_en_dev and ULP table before calling
auxiliary_device_init(), so the release callback only sees a fully
initialized auxiliary private object. If auxiliary_device_init() itself
fails, free those allocations directly because device_initialize() has not
run and the release callback will not be invoked.
This issue was found by a static analysis checker and confirmed by manual
source review. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/vc4: hvs/v3d: Fix null dereference in unbind
The hvs and v3d drivers use dev_get_drvdata(master) in their unbind
functions. Since the vc4-drm gets removed before its dependent drivers
(vc4_hvs/vc4_v3d) the vc4_hvs_unbind/vc4_v3d_unbind functions try to
get drvdata of its master and fails with a null dereference error.
Use the data pointer passed to the unbind functions directly instead of
dev_get_drvdata(master). This avoids using potentially freed memory. |
| In the Linux kernel, the following vulnerability has been resolved:
idpf: fix max_vport related crash on allocation error during init
Set adapter->max_vports only after successful allocation of vports, netdevs
and vport_config buffers. This fixes possible crashes on reset or rmmod,
following failed allocation on init
[ 305.981402] idpf 0000:83:00.0: enabling device (0100 -> 0102)
[ 305.994464] idpf 0000:83:00.0: Device HW Reset initiated
[ 320.416872] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 320.416918] #PF: supervisor read access in kernel mode
[ 320.416942] #PF: error_code(0x0000) - not-present page
[ 320.416963] PGD 2099657067 P4D 0
[ 320.416983] Oops: Oops: 0000 [#1] SMP NOPTI
...
[ 320.417093] RIP: 0010:idpf_remove+0x118/0x200 [idpf]
[ 320.417130] Code: 8b bb 98 09 00 00 e8 17 0f 5b e5 48 8b bb e8 08 00 00 e8 0b 0f 5b e5 66 83 bb 28 06 00 00 00 48 8b bb 20 06 00 00 74 49 31 ed <48> 8b 04 ef 48 85 c0 74 2f 48 8b 78 20 e8 66 58 91 e5 48 8b 83 20
[ 320.417183] RSP: 0018:ff7322212903fdb8 EFLAGS: 00010246
[ 320.417205] RAX: 0000000000000000 RBX: ff4463de40300000 RCX: ff7322212903fd4c
[ 320.417228] RDX: 0000000000000001 RSI: ffffffffa7f7d100 RDI: 0000000000000000
[ 320.417250] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
[ 320.417272] R10: 0000000000000001 R11: ff4463de3a638f58 R12: ff4463be89ac7000
[ 320.417294] R13: ff4463be89ac7198 R14: ff4463be94fc7198 R15: ffffffffc0f10f20
[ 320.417317] FS: 00007f963c0e6740(0000) GS:ff4463fdd65d8000(0000) knlGS:0000000000000000
[ 320.417342] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 320.417362] CR2: 0000000000000000 CR3: 00000020ba674002 CR4: 0000000000773ef0
[ 320.417385] PKRU: 55555554
[ 320.417398] Call Trace:
[ 320.417412] <TASK>
[ 320.417429] pci_device_remove+0x42/0xb0
[ 320.417459] device_release_driver_internal+0x1a9/0x210
[ 320.417492] driver_detach+0x4b/0x90
[ 320.417516] bus_remove_driver+0x70/0x100
[ 320.417539] pci_unregister_driver+0x2e/0xb0
[ 320.417564] __do_sys_delete_module.constprop.0+0x190/0x2f0
[ 320.417592] ? kmem_cache_free+0x31e/0x550
[ 320.417619] ? lockdep_hardirqs_on_prepare+0xde/0x190
[ 320.417644] ? do_syscall_64+0x38/0x6b0
[ 320.417665] do_syscall_64+0xc8/0x6b0
[ 320.417683] ? clear_bhb_loop+0x30/0x80
[ 320.417706] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 320.417727] RIP: 0033:0x7f963bb30beb |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix context pstate override handling
There are several problems in the context pstate handling code.
The most serious ones are potential use-after-free and NULL pointer
dereferences at context initialization time. Both are due
amdgpu_ctx_init() not holding the adev->pm.stable_pstate_ctx_lock, which
is otherwise used from both sysfs and the context code itself for
modifying and clearing the stored context pointer.
Second issue is that context fini can trample over the pstate
configuration set via sysfs. This is due the restore state
(ctx->stable_pstate) being saved at context init time, and not if, or when
the context actually changes the pstate. As the context exits it will
therefore incorrectly restore to what was set before the sysfs override
was requested.
The simplest fix is to drastically simplify how the state is tracked, by
clearly defining the points at which pstate ownership is taken and
released, and to handle all transitions under the correct lock.
Instead of at context init time, the previous state is saved only at the
point the context overrides the current state, and is restored on context
exit only if the context is still the owner of the current override state.
(cherry picked from commit 1b5e413713c0a93bc1818394d0ce49aaad21bd27) |
| In the Linux kernel, the following vulnerability has been resolved:
drm/i915/gt: Fix NULL deref on sched_engine alloc failure
Avoid using intel_context_put() before intel_context_init() in
execlists_create_virtual() as the kref_put() inside would lead
to NULL deref on the IOCTL path when sched_engine allocation fails.
Discovered using AI-assisted static analysis confirmed by
Intel Product Security.
(cherry picked from commit 4f2a12f2d50e9f48227656e4dcbd6423506be31d) |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix kernel panic during driver load failure
Avoid kernel panic if MES init fails during driver load. The KIQ ring is
falsely marked as ready as ASICs that use MES, KIQ is owned by MES.
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: 0010:gfx_v12_1_wait_reg_mem+0x5a/0x1f0 [amdgpu]
Call Trace:
gfx_v12_1_ring_emit_reg_write_reg_wait+0x1f/0x30 [amdgpu]
amdgpu_gmc_fw_reg_write_reg_wait+0xb2/0x190 [amdgpu]
amdgpu_gmc_flush_gpu_tlb+0x1cc/0x230 [amdgpu]
amdgpu_gart_invalidate_tlb+0x81/0xa0 [amdgpu]
amdgpu_gart_unbind+0x72/0x90 [amdgpu]
amdgpu_ttm_backend_unbind+0xa4/0xb0 [amdgpu]
amdgpu_ttm_tt_unpopulate+0x13/0xd0 [amdgpu]
amdttm_tt_unpopulate+0x29/0x70 [amdttm]
ttm_bo_put+0x1eb/0x360 [amdttm]
amdgpu_bo_free_kernel+0xf9/0x1f0 [amdgpu]
amdgpu_ih_ring_fini+0x5a/0x90 [amdgpu]
amdgpu_irq_fini_hw+0x58/0x80 [amdgpu]
amdgpu_device_fini_hw+0x4e0/0x5b0 [amdgpu]
amdgpu_driver_load_kms+0x60/0xa0 [amdgpu]
amdgpu_pci_probe+0x28e/0x6d0 [amdgpu]
pci_device_probe+0x19f/0x220
really_probe+0x1ed/0x340
driver_probe_device+0x1e/0x80
__driver_attach+0xd3/0x1a0
bus_for_each_dev+0x68/0xa0
bus_add_driver+0x19f/0x270
driver_register+0x5d/0xf0
do_one_initcall+0xac/0x200
do_init_module+0x1ec/0x280
__se_sys_finit_module+0x2de/0x310
do_syscall_64+0x6a/0x250
entry_SYSCALL_64_after_hwframe+0x4b/0x53
(cherry picked from commit 4623b958dd6da0f4c3026afdf330626a09ecb0f0) |
| In the Linux kernel, the following vulnerability has been resolved:
net: team: fix NULL pointer dereference in team_xmit during mode change
__team_change_mode() clears team->ops with memset() before restoring
safe dummy handlers via team_adjust_ops(). A concurrent team_xmit()
running under RCU on another CPU can read team->ops.transmit during
this window and call a NULL function pointer, crashing the kernel.
The race requires a mode change (CAP_NET_ADMIN) concurrent with
transmit on the team device.
BUG: kernel NULL pointer dereference, address: 0000000000000000
Oops: 0010 [#1] SMP KASAN NOPTI
RIP: 0010:0x0
Call Trace:
team_xmit (drivers/net/team/team_core.c:1853)
dev_hard_start_xmit (net/core/dev.c:3904)
__dev_queue_xmit (net/core/dev.c:4871)
packet_sendmsg (net/packet/af_packet.c:3109)
__sys_sendto (net/socket.c:2265)
The original code assumed that no ports means no traffic, so mode
changes could freely memset()/memcpy() the ops. AF_PACKET with
forced carrier breaks that assumption.
Prevent the race instead of making it safe: replace memset()/memcpy()
with per-field updates that never touch transmit or receive. Those
two handlers are managed solely by team_adjust_ops(), which already
installs dummies when tx_en_port_count == 0 (always true during mode
change since no ports are present). WRITE_ONCE/READ_ONCE prevent
store/load tearing on the handler pointers.
synchronize_net() before exit_op() drains in-flight readers that may
still reference old mode state from before port removal switched the
handlers to dummies. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: allocate hook ops while under mutex
arp/ip(6)t_register_table() add the table to the per-netns list via
xt_register_table() before allocating the per-netns hook ops copy
via kmemdup_array(). This leaves a window where the table is
visible in the list with ops=NULL.
If the pernet exit happens runs concurrently the pre_exit callback finds
the table via xt_find_table() and passes the NULL ops pointer to
nf_unregister_net_hooks(), causing a NULL dereference:
general protection fault in nf_unregister_net_hooks+0xbc/0x150
RIP: nf_unregister_net_hooks (net/netfilter/core.c:613)
Call Trace:
ipt_unregister_table_pre_exit
iptable_mangle_net_pre_exit
ops_pre_exit_list
cleanup_net
Fix by moving the ops allocation into the xtables core so the table is
never in the list without valid ops. Also ensure the table is no longer
processing packets before its torn down on error unwind.
nf_register_net_hooks might have published at least one hook; call
synchronize_rcu() if there was an error.
audit log register message gets deferred until all operations have
passed, this avoids need to emit another ureg message in case of
error unwinding.
Based on earlier patch by Tristan Madani. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: read COW data with the original inode during atomic write
When updating an atomic-write file, f2fs_write_begin() may read the
previously written data back from the COW inode:
prepare_atomic_write_begin() locates the block in the COW inode and sets
use_cow, and the read bio is then built with the COW inode:
f2fs_submit_page_read(use_cow ? F2FS_I(inode)->cow_inode : inode,
...);
and f2fs_grab_read_bio() decides whether to schedule fs-layer decryption
(STEP_DECRYPT) for the bio based on that inode via
fscrypt_inode_uses_fs_layer_crypto().
However, the folio being filled belongs to the original inode
(folio->mapping->host == inode), and the data stored in the COW block was
encrypted (or left as plaintext) using the original inode's context, not
the COW inode's -- see f2fs_encrypt_one_page(), which keys off
fio->page->mapping->host. fscrypt_decrypt_pagecache_blocks() likewise
operates on folio->mapping->host.
The COW inode is created as a tmpfile in the parent directory and inherits
its encryption policy from there. With test_dummy_encryption the newly
created COW inode gets the dummy policy and becomes encrypted, while a
pre-existing regular file -- created before the policy applied, e.g.
already present in the on-disk image -- stays unencrypted. The read
path then sets STEP_DECRYPT based on the encrypted COW inode and calls
fscrypt_decrypt_pagecache_blocks() on a folio whose host (the unencrypted
original inode) has a NULL ->i_crypt_info, dereferencing it:
Oops: general protection fault, probably for non-canonical address ...
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
RIP: 0010:fscrypt_decrypt_pagecache_blocks+0xa0/0x310
Workqueue: f2fs_post_read_wq f2fs_post_read_work
Call Trace:
fscrypt_decrypt_bio+0x1eb/0x340
f2fs_post_read_work+0xba/0x140
process_one_work+0x91c/0x1a40
worker_thread+0x677/0xe90
kthread+0x2bc/0x3a0
The COW inode is only needed to locate the on-disk block, and that block
address is already resolved into @blkaddr by prepare_atomic_write_begin()
via __find_data_block(cow_inode, ...); f2fs_submit_page_read() then reads
from that physical @blkaddr directly, so the inode argument only selects
the post-read crypto context, not which block is fetched. Reading with
@inode therefore returns the same (latest, not-yet-committed) COW data,
while making both the fs-layer decryption decision and the inline crypto
path use the correct (original inode's) key.
With the COW inode no longer used at the read site, the use_cow flag has no
remaining consumer; drop it from f2fs_write_begin() and
prepare_atomic_write_begin(). |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Avoid NULL dereference in dc_dmub_srv error paths
In dc_dmub_srv_log_diagnostic_data() and
dc_dmub_srv_enable_dpia_trace().
Both functions check:
if (!dc_dmub_srv || !dc_dmub_srv->dmub)
and then call DC_LOG_ERROR() inside that block.
DC_LOG_ERROR() uses dc_dmub_srv->ctx internally. So if
dc_dmub_srv is NULL, the logging itself can dereference a
NULL pointer and cause a crash.
Fix this by splitting the checks.
First check if dc_dmub_srv is NULL and return immediately.
Then check dc_dmub_srv->dmub and log the error only when
dc_dmub_srv is valid.
Fixes the below:
../display/dc/dc_dmub_srv.c:962 dc_dmub_srv_log_diagnostic_data() error: we previously assumed 'dc_dmub_srv' could be null (see line 961)
../display/dc/dc_dmub_srv.c:1167 dc_dmub_srv_enable_dpia_trace() error: we previously assumed 'dc_dmub_srv' could be null (see line 1166) |
| In the Linux kernel, the following vulnerability has been resolved:
net: mana: Guard mana_remove against double invocation
If PM resume fails (e.g., mana_attach() returns an error), mana_probe()
calls mana_remove(), which tears down the device and sets
gd->gdma_context = NULL and gd->driver_data = NULL.
However, a failed resume callback does not automatically unbind the
driver. When the device is eventually unbound, mana_remove() is invoked
a second time. Without a NULL check, it dereferences gc->dev with
gc == NULL, causing a kernel panic.
Add an early return if gdma_context or driver_data is NULL so the second
invocation is harmless. Move the dev = gc->dev assignment after the
guard so it cannot dereference NULL. |
