1
0
Fork 0
mirror of synced 2025-03-06 20:59:54 +01:00
linux/kernel
Kuniyuki Iwashima 5da7e15fb5 net: Add rx_skb of kfree_skb to raw_tp_null_args[].
Yan Zhai reported a BPF prog could trigger a null-ptr-deref [0]
in trace_kfree_skb if the prog does not check if rx_sk is NULL.

Commit c53795d48e ("net: add rx_sk to trace_kfree_skb") added
rx_sk to trace_kfree_skb, but rx_sk is optional and could be NULL.

Let's add kfree_skb to raw_tp_null_args[] to let the BPF verifier
validate such a prog and prevent the issue.

Now we fail to load such a prog:

  libbpf: prog 'drop': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0
  ; int BPF_PROG(drop, struct sk_buff *skb, void *location, @ kfree_skb_sk_null.bpf.c:21
  0: (79) r3 = *(u64 *)(r1 +24)
  func 'kfree_skb' arg3 has btf_id 5253 type STRUCT 'sock'
  1: R1=ctx() R3_w=trusted_ptr_or_null_sock(id=1)
  ; bpf_printk("sk: %d, %d\n", sk, sk->__sk_common.skc_family); @ kfree_skb_sk_null.bpf.c:24
  1: (69) r4 = *(u16 *)(r3 +16)
  R3 invalid mem access 'trusted_ptr_or_null_'
  processed 2 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --

Note this fix requires commit 838a10bd2e ("bpf: Augment raw_tp
arguments with PTR_MAYBE_NULL").

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000010
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP
RIP: 0010:bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x148/0x420
 ? search_bpf_extables+0x5b/0x70
 ? fixup_exception+0x27/0x2c0
 ? exc_page_fault+0x75/0x170
 ? asm_exc_page_fault+0x22/0x30
 ? bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
 bpf_trace_run4+0x68/0xd0
 ? unix_stream_connect+0x1f4/0x6f0
 sk_skb_reason_drop+0x90/0x120
 unix_stream_connect+0x1f4/0x6f0
 __sys_connect+0x7f/0xb0
 __x64_sys_connect+0x14/0x20
 do_syscall_64+0x47/0xc30
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: c53795d48e ("net: add rx_sk to trace_kfree_skb")
Reported-by: Yan Zhai <yan@cloudflare.com>
Closes: https://lore.kernel.org/netdev/Z50zebTRzI962e6X@debian.debian/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Yan Zhai <yan@cloudflare.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20250201030142.62703-1-kuniyu@amazon.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-06 02:46:00 -08:00
..
bpf net: Add rx_skb of kfree_skb to raw_tp_null_args[]. 2025-02-06 02:46:00 -08:00
cgroup drm next for 6.14-rc1 2025-01-21 16:09:47 -08:00
configs configs/debug: make sure PROVE_RCU_LIST=y takes effect 2024-10-28 10:21:09 -07:00
debug kdb: Remove unused flags stack 2025-01-25 08:22:26 +00:00
dma dma-debug: fix physical address calculation for struct dma_debug_entry 2024-11-28 10:19:16 +01:00
entry sched: Add TIF_NEED_RESCHED_LAZY infrastructure 2024-11-05 12:55:37 +01:00
events Performance events changes for v6.14: 2025-01-21 10:52:03 -08:00
futex Mainly individually changelogged singleton patches. The patch series in 2025-01-26 17:50:53 -08:00
gcov gcov: clang: use correct function param names 2025-01-24 22:47:27 -08:00
irq Updates for the interrupt subsystem: 2025-01-21 13:51:07 -08:00
kcsan kcsan: Remove redundant call of kallsyms_lookup_name() 2024-10-14 16:44:56 +02:00
livepatch livepatch: Add stack_order sysfs attribute 2024-12-09 11:44:03 +01:00
locking RCU pull request for v6.14 2025-01-21 14:39:21 -08:00
module Driver core and debugfs updates 2025-01-28 12:25:12 -08:00
power The various patchsets are summarized below. Plus of course many 2025-01-26 18:36:23 -08:00
printk Merge branch 'for-6.14-cpu_sync-fixup' into for-linus 2025-01-20 13:40:52 +01:00
rcu The various patchsets are summarized below. Plus of course many 2025-01-26 18:36:23 -08:00
sched The various patchsets are summarized below. Plus of course many 2025-01-26 18:36:23 -08:00
time Updates for timers and timekeeping: 2025-01-21 13:16:00 -08:00
trace rv: tools/rtla: Updates for 6.14 2025-01-26 14:25:58 -08:00
.gitignore
acct.c acct: avoid pointless reference count bump 2024-12-02 11:25:13 +01:00
async.c async: Use a dedicated unbound workqueue with raised min_active 2024-02-09 11:13:59 -10:00
audit.c lsm: replace context+len with lsm_context 2024-12-04 14:42:31 -05:00
audit.h audit: change context data from secid to lsm_prop 2024-10-11 14:34:16 -04:00
audit_fsnotify.c
audit_tree.c fsnotify: create a wrapper fsnotify_find_inode_mark() 2024-04-04 16:24:16 +02:00
audit_watch.c fsnotify: create a wrapper fsnotify_find_inode_mark() 2024-04-04 16:24:16 +02:00
auditfilter.c audit: fix suffixed '/' filename matching 2024-12-05 19:22:38 -05:00
auditsc.c lsm/stable-6.14 PR 20250121 2025-01-21 20:03:04 -08:00
backtracetest.c backtracetest: add MODULE_DESCRIPTION() 2024-06-24 22:24:55 -07:00
bounds.c bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS 2024-04-29 08:29:29 -07:00
capability.c kernel: remove get_task_comm() and print task comm directly 2025-01-12 20:21:15 -08:00
cfi.c
compat.c
configs.c
context_tracking.c context_tracking, rcu: Rename rcu_dyntick trace event into rcu_watching 2024-08-15 21:30:43 +05:30
cpu.c The various patchsets are summarized below. Plus of course many 2025-01-26 18:36:23 -08:00
cpu_pm.c
crash_core.c kexec/crash: no crash update when kexec in progress 2024-11-05 17:12:27 -08:00
crash_reserve.c crash: fix crash memory reserve exceed system memory bug 2024-09-01 20:43:30 -07:00
cred.c cred: remove old {override,revert}_creds() helpers 2024-12-02 11:25:09 +01:00
delayacct.c delayacct: add delay min to record delay peak 2025-01-12 20:21:16 -08:00
dma.c
elfcorehdr.c crash: remove dependency of FA_DUMP on CRASH_DUMP 2024-02-23 17:48:22 -08:00
exec_domain.c
exit.c remove pointless includes of <linux/fdtable.h> 2024-10-07 13:34:41 -04:00
exit.h
extable.c
fail_function.c
fork.c Mainly individually changelogged singleton patches. The patch series in 2025-01-26 17:50:53 -08:00
freezer.c sched/fair: Fix external p->on_rq users 2024-10-14 09:14:35 +02:00
gen_kheaders.sh kheaders: Ignore silly-rename files 2024-12-20 22:07:55 +01:00
groups.c
hung_task.c hung_task: add task->flags, blocked by coredump to log 2025-01-24 22:47:24 -08:00
iomem.c
irq_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
jump_label.c jump_label: Fix static_key_slow_dec() yet again 2024-09-10 11:57:27 +02:00
kallsyms.c kallsyms: Match symbols exactly with CONFIG_LTO_CLANG 2024-08-15 09:33:35 -07:00
kallsyms_internal.h kallsyms: get rid of code for absolute kallsyms 2024-07-20 16:33:21 +09:00
kallsyms_selftest.c kallsyms: Use kthread_run_on_cpu() 2025-01-02 22:12:12 +01:00
kallsyms_selftest.h
kcmp.c get rid of ...lookup...fdget_rcu() family 2024-10-07 13:34:41 -04:00
Kconfig.freezer
Kconfig.hz
Kconfig.kexec crash, powerpc: default to CRASH_DUMP=n on PPC_BOOK3S_32 2024-11-14 22:43:48 -08:00
Kconfig.locks
Kconfig.preempt sched: No PREEMPT_RT=y for all{yes,mod}config 2024-11-07 15:25:05 +01:00
kcov.c kcov: mark in_softirq_really() as __always_inline 2024-12-30 17:59:08 -08:00
kexec.c crash: add a new kexec flag for hotplug support 2024-04-23 14:59:01 +10:00
kexec_core.c kexec_core: Add and update comments regarding the KEXEC_JUMP flow 2025-01-14 13:03:34 +01:00
kexec_elf.c
kexec_file.c kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=y 2024-09-01 17:59:01 -07:00
kexec_internal.h kexec: use atomic_try_cmpxchg_acquire() in kexec_trylock() 2024-09-01 20:43:23 -07:00
kheaders.c kheaders: Simplify attribute through __BIN_ATTR_SIMPLE_RO() 2024-12-24 09:46:49 +01:00
kprobes.c kprobes: Remove remaining gotos 2025-01-10 09:00:13 +09:00
ksyms_common.c
ksysfs.c kernel/ksysfs.c: simplify bin_attribute definition 2025-01-07 16:59:15 +01:00
kthread.c Mainly individually changelogged singleton patches. The patch series in 2025-01-26 17:50:53 -08:00
latencytop.c latencytop: use correct kernel-doc format for func params 2025-01-24 22:47:27 -08:00
Makefile mm: move kernel/numa.c to mm/ 2024-09-03 21:15:26 -07:00
module_signature.c
notifier.c reboot: move reboot_notifier_list to kernel/reboot.c 2024-11-05 17:12:31 -08:00
nsproxy.c fdget(), trivial conversions 2024-11-03 01:28:06 -05:00
padata.c padata: avoid UAF for reorder_work 2025-01-19 12:44:28 +08:00
panic.c drm next for 6.12-rc1 2024-09-19 10:18:15 +02:00
params.c module: Constify 'struct module_attribute' 2025-01-26 13:05:23 +01:00
pid.c kernel-6.14-rc1.pid 2025-01-20 10:29:11 -08:00
pid_namespace.c pid: allow pid_max to be set per pid namespace 2024-12-02 11:25:25 +01:00
pid_sysctl.h sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
profile.c profiling: remove profile=sleep support 2024-08-04 13:36:28 -07:00
ptrace.c ptrace_attach: shift send(SIGSTOP) into ptrace_set_stopped() 2024-02-22 15:38:52 -08:00
range.c
reboot.c kernel/reboot: replace sprintf() with sysfs_emit() 2024-11-11 17:17:05 -08:00
regset.c regset: use kvzalloc() for regset_get_alloc() 2024-04-25 21:07:03 -07:00
relay.c [tree-wide] finally take no_llseek out 2024-09-27 08:18:43 -07:00
resource.c kernel/resource: simplify API __devm_release_region() implementation 2025-01-12 20:20:58 -08:00
resource_kunit.c resource, kunit: fix user-after-free in resource_test_region_intersects() 2024-10-09 12:47:19 -07:00
rseq.c rseq: Fix rseq unregistration regression 2025-01-21 08:10:51 +01:00
scftorture.c scftorture: Handle NULL argument passed to scf_add_to_free_list(). 2024-11-14 16:09:51 -08:00
scs.c
seccomp.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
signal.c signal/posixtimers: Handle ignore/blocked sequences correctly 2025-01-15 18:08:01 +01:00
smp.c CSD-lock pull request for v6.14 2025-01-28 11:34:03 -08:00
smpboot.c
smpboot.h
softirq.c softirq: Allow raising SCHED_SOFTIRQ from SMP-call-function on RT kernel 2024-12-02 12:01:27 +01:00
stackleak.c stackleak: Use str_enabled_disabled() helper in stack_erasing_sysctl() 2024-12-22 20:28:11 -08:00
stacktrace.c stacktrace: fix kernel-doc typo 2023-12-29 12:22:29 -08:00
static_call.c
static_call_inline.c x86/static-call: provide a way to do very early static-call updates 2024-12-13 09:28:32 +01:00
stop_machine.c stop_machine: Fix rcu_momentary_eqs() call in multi_cpu_stop() 2024-12-11 20:50:47 -08:00
sys.c tracing: Add task_prctl_unknown tracepoint 2024-12-22 20:28:11 -08:00
sys_ni.c Probes updates for v6.11: 2024-07-18 12:19:20 -07:00
sysctl-test.c sysctl: Add module description to sysctl-testing 2024-06-03 15:20:37 +02:00
sysctl.c pid: allow pid_max to be set per pid namespace 2024-12-02 11:25:25 +01:00
task_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
taskstats.c fdget(), more trivial conversions 2024-11-03 01:28:06 -05:00
torture.c torture: Add MODULE_DESCRIPTION() 2024-05-30 15:31:38 -07:00
tracepoint.c tracing: Fix syscall tracepoint use-after-free 2024-11-01 14:37:31 -04:00
tsacct.c tsacct: replace strncpy() with strscpy() 2024-07-12 16:39:53 -07:00
ucount.c ucounts: move kfree() out of critical zone protected by ucounts_lock 2025-01-12 20:21:00 -08:00
uid16.c
uid16.h
umh.c remove pointless includes of <linux/fdtable.h> 2024-10-07 13:34:41 -04:00
up.c
user-return-notifier.c
user.c uidgid: make sure we fit into one cacheline 2024-09-12 12:16:09 +02:00
user_namespace.c user_namespace: use kmemdup_array() instead of kmemdup() for multiple allocation 2024-09-09 16:47:42 -07:00
usermode_driver.c
utsname.c
utsname_sysctl.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
vhost_task.c vhost_task: Handle SIGKILL by flushing work and exiting 2024-05-22 08:31:15 -04:00
vmcore_info.c mm: support only one page_type per page 2024-09-03 21:15:43 -07:00
watch_queue.c watch_queue: Use page->private instead of page->index 2024-12-22 11:29:51 +01:00
watchdog.c watchdog: output this_cpu when printing hard LOCKUP 2025-01-12 20:21:05 -08:00
watchdog_buddy.c
watchdog_perf.c watchdog/perf: properly initialize the turbo mode timestamp and rearm counter 2024-07-17 21:11:34 -07:00
workqueue.c The various patchsets are summarized below. Plus of course many 2025-01-26 18:36:23 -08:00
workqueue_internal.h