In the Linux kernel, the following vulnerability has been resolved:
hwmon: (pmbus/adm1266) reject implausible blackbox record_count
adm1266_nvmem_read_blackbox() loops over a record_count that comes
straight from byte 3 of the BLACKBOX_INFO response. The destination
buffer is data->dev_mem, sized for the nvmem cell's declared 2048
bytes (ADM1266_BLACKBOX_MAX_RECORDS * ADM1266_BLACKBOX_SIZE = 32 * 64).
A device that reports a record_count greater than 32 -- whether due
to firmware bugs, bus corruption, or a non-responsive slave returning
0xff -- would walk read_buff past the end of the dev_mem allocation
on the trailing iterations.
Cap record_count at ADM1266_BLACKBOX_MAX_RECORDS (introduced here)
before entering the loop and return -EIO on any larger value, so a
malformed BLACKBOX_INFO response cannot drive the loop out of bounds.
In the Linux kernel, the following vulnerability has been resolved:
fs/statmount: fix slab out-of-bounds write in statmount_mnt_idmap
statmount_mnt_idmap() writes one mapping with seq_printf() and then
manually advances seq->count to include the NUL separator.
If seq_printf() overflows, seq_set_overflow() sets seq->count to
seq->size. The manual seq->count++ changes this to seq->size + 1.
seq_has_overflowed() then no longer detects the overflow. The corrupted
count returns to statmount_string(), which later executes:
seq->buf[seq->count++] = '\0';
This causes a 1-byte NULL out-of-bounds write on the dynamically
allocated seq buffer.
Fix this by checking for overflow immediately after seq_printf().
In the Linux kernel, the following vulnerability has been resolved:
fprobe: Fix unregister_fprobe() to wait for RCU grace period
Commit 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
changed fprobe to register struct fprobe to an rcu-hlist, but it forgot
to wait for RCU GP. Thus there can be use-after-free if the fprobe is
released right after unregistering. This can be happened on fprobe
event and sample module code.
To fix this issue, add synchronize_rcu() in unregister_fprobe().
Note that BPF is OK because fprobe is used as a part of
bpf_kprobe_multi_link. This unregisters its fprobe in
bpf_kprobe_multi_link_release() and it is deallocated via
bpf_kprobe_multi_link_dealloc(), which is invoked from
bpf_link_defer_dealloc_rcu_gp() RCU callback.
For BPF, this also introduced unregister_fprobe_async() which does
NOT wait for RCU grace priod.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: bridge: eb_tables: close module init race
sashiko reports for unrelated patch:
Does the core ebtables initialization in ebtables.c suffer from a similar race?
Once nf_register_sockopt() completes, the sockopts are exposed globally.
sockopt has to be registered last, just like in ip/ip6/arptables.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ebtables: move to two-stage removal scheme
Like previous patches for x_tables, follow same pattern in ebtables.
We can't reuse xt helpers: ebt_table struct layout is incompatible.
table->ops assignment is now done while still holding the ebt mutex
to make sure we never expose partially-filled table struct.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: add and use xtables_unregister_table_exit
Previous change added xtables_unregister_table_pre_exit to detach the
table from the packetpath and to unlink it from the active table list.
In case of rmmod, userspace that is doing set/getsockopt for this table
will not be able to re-instantiate the table:
1. The larval table has been removed already
2. existing instantiated table is no longer on the xt pernet table list.
This adds the second stage helper:
unlink the table from the dying list, free the hook ops (if any) and do
the audit notification. It replaces xt_unregister_table().
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:
firmware: arm_ffa: Snapshot notifier callbacks under lock
Both notification handlers currently look up a notifier callback under
notify_lock, drop the lock, and then dereference the returned
notifier entry. A concurrent unregister can delete and free that
entry in the gap, leaving the handler to dereference stale memory.
Copy the callback pointer and callback data while notify_lock is
still held and invoke the callback only after the lock is dropped.
This keeps the existing callback execution model while removing the
use-after-free window in both the framework and non-framework
notification paths.
In the Linux kernel, the following vulnerability has been resolved:
firmware: arm_ffa: Validate framework notification message layout
Framework notifications carry an indirect message in the shared RX
buffer. Validate the reported offset and size before using them, reject
zero-length payloads, and ensure that any non-header payload starts at
the UUID field rather than in the middle of the message header.
Use the validated offset and size values for both kmemdup() and the UUID
parsing path so malformed firmware data cannot drive an out-of-bounds
read or an oversized allocation.
In the Linux kernel, the following vulnerability has been resolved:
riscv: Fix register corruption from uninitialized cregs on error
compat_riscv_gpr_set() calls cregs_to_regs() unconditionally, even when
user_regset_copyin() fails. Since cregs is an uninitialized stack
variable, a copyin failure causes uninitialized stack data to be written
into the target task's pt_regs, corrupting its register state and
potentially leaking kernel stack contents.
compat_restore_sigcontext() has the same issue: it calls cregs_to_regs()
even when __copy_from_user() fails, leading to the same corruption of
the signal-returning task's register state on error.
Only call cregs_to_regs() when the user copy succeeds.