Security Vulnerabilities
- CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: Fix dereference of null pointer flow
In the case where chain->flags & NFT_CHAIN_HW_OFFLOAD is false then
nft_flow_rule_create is not called and flow is NULL. The subsequent
error handling execution via label err_destroy_flow_rule will lead
to a null pointer dereference on flow when calling nft_flow_rule_destroy.
Since the error path to err_destroy_flow_rule has to cater for null
and non-null flows, only call nft_flow_rule_destroy if flow is non-null
to fix this issue.
Addresses-Coverity: ("Explicity null dereference")
In the Linux kernel, the following vulnerability has been resolved:
cpufreq: CPPC: Fix potential memleak in cppc_cpufreq_cpu_init
It's a classic example of memleak, we allocate something, we fail and
never free the resources.
Make sure we free all resources on policy ->init() failures.
In the Linux kernel, the following vulnerability has been resolved:
memory: fsl_ifc: fix leak of private memory on probe failure
On probe error the driver should free the memory allocated for private
structure. Fix this by using resource-managed allocation.
In the Linux kernel, the following vulnerability has been resolved:
memory: fsl_ifc: fix leak of IO mapping on probe failure
On probe error the driver should unmap the IO memory. Smatch reports:
drivers/memory/fsl_ifc.c:298 fsl_ifc_ctrl_probe() warn: 'fsl_ifc_ctrl_dev->gregs' not released on lines: 298.
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix NULL dereference in nfs3svc_encode_getaclres
In error cases the dentry may be NULL.
Before 20798dfe249a, the encoder also checked dentry and
d_really_is_positive(dentry), but that looks like overkill to me--zero
status should be enough to guarantee a positive dentry.
This isn't the first time we've seen an error-case NULL dereference
hidden in the initialization of a local variable in an xdr encoder. But
I went back through the other recent rewrites and didn't spot any
similar bugs.
In the Linux kernel, the following vulnerability has been resolved:
scsi: target: Fix NULL dereference on XCOPY completion
CPU affinity control added with commit 39ae3edda325 ("scsi: target: core:
Make completion affinity configurable") makes target_complete_cmd() queue
work on a CPU based on se_tpg->se_tpg_wwn->cmd_compl_affinity state.
LIO's EXTENDED COPY worker is a special case in that read/write cmds are
dispatched using the global xcopy_pt_tpg, which carries a NULL se_tpg_wwn
pointer following initialization in target_xcopy_setup_pt().
The NULL xcopy_pt_tpg->se_tpg_wwn pointer is dereferenced on completion of
any EXTENDED COPY initiated read/write cmds. E.g using the libiscsi
SCSI.ExtendedCopy.Simple test:
BUG: kernel NULL pointer dereference, address: 00000000000001a8
RIP: 0010:target_complete_cmd+0x9d/0x130 [target_core_mod]
Call Trace:
fd_execute_rw+0x148/0x42a [target_core_file]
? __dynamic_pr_debug+0xa7/0xe0
? target_check_reservation+0x5b/0x940 [target_core_mod]
__target_execute_cmd+0x1e/0x90 [target_core_mod]
transport_generic_new_cmd+0x17c/0x330 [target_core_mod]
target_xcopy_issue_pt_cmd+0x9/0x60 [target_core_mod]
target_xcopy_read_source.isra.7+0x10b/0x1b0 [target_core_mod]
? target_check_fua+0x40/0x40 [target_core_mod]
? transport_complete_task_attr+0x130/0x130 [target_core_mod]
target_xcopy_do_work+0x61f/0xc00 [target_core_mod]
This fix makes target_complete_cmd() queue work on se_cmd->cpuid if
se_tpg_wwn is NULL.
In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions
While running the self-tests on a KASAN enabled kernel, I observed a
slab-out-of-bounds splat very similar to the one reported in
commit 821bbf79fe46 ("ipv6: Fix KASAN: slab-out-of-bounds Read in
fib6_nh_flush_exceptions").
We additionally need to take care of fib6_metrics initialization
failure when the caller provides an nh.
The fix is similar, explicitly free the route instead of calling
fib6_info_release on a half-initialized object.
In the Linux kernel, the following vulnerability has been resolved:
io_uring: fix memleak in io_init_wq_offload()
I got memory leak report when doing fuzz test:
BUG: memory leak
unreferenced object 0xffff888107310a80 (size 96):
comm "syz-executor.6", pid 4610, jiffies 4295140240 (age 20.135s)
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N..........
backtrace:
[<000000001974933b>] kmalloc include/linux/slab.h:591 [inline]
[<000000001974933b>] kzalloc include/linux/slab.h:721 [inline]
[<000000001974933b>] io_init_wq_offload fs/io_uring.c:7920 [inline]
[<000000001974933b>] io_uring_alloc_task_context+0x466/0x640 fs/io_uring.c:7955
[<0000000039d0800d>] __io_uring_add_tctx_node+0x256/0x360 fs/io_uring.c:9016
[<000000008482e78c>] io_uring_add_tctx_node fs/io_uring.c:9052 [inline]
[<000000008482e78c>] __do_sys_io_uring_enter fs/io_uring.c:9354 [inline]
[<000000008482e78c>] __se_sys_io_uring_enter fs/io_uring.c:9301 [inline]
[<000000008482e78c>] __x64_sys_io_uring_enter+0xabc/0xc20 fs/io_uring.c:9301
[<00000000b875f18f>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<00000000b875f18f>] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
[<000000006b0a8484>] entry_SYSCALL_64_after_hwframe+0x44/0xae
CPU0 CPU1
io_uring_enter io_uring_enter
io_uring_add_tctx_node io_uring_add_tctx_node
__io_uring_add_tctx_node __io_uring_add_tctx_node
io_uring_alloc_task_context io_uring_alloc_task_context
io_init_wq_offload io_init_wq_offload
hash = kzalloc hash = kzalloc
ctx->hash_map = hash ctx->hash_map = hash <- one of the hash is leaked
When calling io_uring_enter() in parallel, the 'hash_map' will be leaked,
add uring_lock to protect 'hash_map'.
In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_skbmod: Skip non-Ethernet packets
Currently tcf_skbmod_act() assumes that packets use Ethernet as their L2
protocol, which is not always the case. As an example, for CAN devices:
$ ip link add dev vcan0 type vcan
$ ip link set up vcan0
$ tc qdisc add dev vcan0 root handle 1: htb
$ tc filter add dev vcan0 parent 1: protocol ip prio 10 \
matchall action skbmod swap mac
Doing the above silently corrupts all the packets. Do not perform skbmod
actions for non-Ethernet packets.
In the Linux kernel, the following vulnerability has been resolved:
netrom: Decrease sock refcount when sock timers expire
Commit 63346650c1a9 ("netrom: switch to sock timer API") switched to use
sock timer API. It replaces mod_timer() by sk_reset_timer(), and
del_timer() by sk_stop_timer().
Function sk_reset_timer() will increase the refcount of sock if it is
called on an inactive timer, hence, in case the timer expires, we need to
decrease the refcount ourselves in the handler, otherwise, the sock
refcount will be unbalanced and the sock will never be freed.