there is one dwc3 trace event declare as below,
DECLARE_EVENT_CLASS(dwc3_log_event,
TP_PROTO(u32 event, struct dwc3 *dwc),
TP_ARGS(event, dwc),
TP_STRUCT__entry(
__field(u32, event)
__field(u32, ep0state)
__dynamic_array(char, str, DWC3_MSG_MAX)
),
TP_fast_assign(
__entry->event = event;
__entry->ep0state = dwc->ep0state;
),
TP_printk("event (%08x): %s", __entry->event,
dwc3_decode_event(__get_str(str), DWC3_MSG_MAX,
__entry->event, __entry->ep0state))
);
the problem is when trace function called, it will allocate up to
DWC3_MSG_MAX bytes from trace event buffer, but never fill the buffer
during fast assignment, it only fill the buffer when output function are
called, so this means if output function are not called, the buffer will
never used.
add __get_buf(len) which acquiree buffer from iter->tmp_seq when trace
output function called, it allow user write string to acquired buffer.
the mentioned dwc3 trace event will changed as below,
DECLARE_EVENT_CLASS(dwc3_log_event,
TP_PROTO(u32 event, struct dwc3 *dwc),
TP_ARGS(event, dwc),
TP_STRUCT__entry(
__field(u32, event)
__field(u32, ep0state)
),
TP_fast_assign(
__entry->event = event;
__entry->ep0state = dwc->ep0state;
),
TP_printk("event (%08x): %s", __entry->event,
dwc3_decode_event(__get_buf(DWC3_MSG_MAX), DWC3_MSG_MAX,
__entry->event, __entry->ep0state))
);.
Link: https://lore.kernel.org/linux-trace-kernel/1675065249-23368-1-git-send-email-quic_linyyuan@quicinc.com
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Allow a stacktrace from one event to be displayed by the end event of a
synthetic event. This is very useful when looking for the longest latency
of a sleep or something blocked on I/O.
# cd /sys/kernel/tracing/
# echo 's:block_lat pid_t pid; u64 delta; unsigned long[] stack;' > dynamic_events
# echo 'hist:keys=next_pid:ts=common_timestamp.usecs,st=stacktrace if prev_state == 1||prev_state == 2' > events/sched/sched_switch/trigger
# echo 'hist:keys=prev_pid:delta=common_timestamp.usecs-$ts,s=$st:onmax($delta).trace(block_lat,prev_pid,$delta,$s)' >> events/sched/sched_switch/trigger
The above creates a "block_lat" synthetic event that take the stacktrace of
when a task schedules out in either the interruptible or uninterruptible
states, and on a new per process max $delta (the time it was scheduled
out), will print the process id and the stacktrace.
# echo 1 > events/synthetic/block_lat/enable
# cat trace
# TASK-PID CPU# ||||| TIMESTAMP FUNCTION
# | | | ||||| | |
kworker/u16:0-767 [006] d..4. 560.645045: block_lat: pid=767 delta=66 stack=STACK:
=> __schedule
=> schedule
=> pipe_read
=> vfs_read
=> ksys_read
=> do_syscall_64
=> 0x966000aa
<idle>-0 [003] d..4. 561.132117: block_lat: pid=0 delta=413787 stack=STACK:
=> __schedule
=> schedule
=> schedule_hrtimeout_range_clock
=> do_sys_poll
=> __x64_sys_poll
=> do_syscall_64
=> 0x966000aa
<...>-153 [006] d..4. 562.068407: block_lat: pid=153 delta=54 stack=STACK:
=> __schedule
=> schedule
=> io_schedule
=> rq_qos_wait
=> wbt_wait
=> __rq_qos_throttle
=> blk_mq_submit_bio
=> submit_bio_noacct_nocheck
=> ext4_bio_write_page
=> mpage_submit_page
=> mpage_process_page_bufs
=> mpage_prepare_extent_to_map
=> ext4_do_writepages
=> ext4_writepages
=> do_writepages
=> __writeback_single_inode
Link: https://lkml.kernel.org/r/20230117152236.010941267@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Ross Zwisler <zwisler@google.com>
Cc: Ching-lin Yu <chinglinyu@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Allow to save stacktraces into a histogram variable. This will be used by
synthetic events to allow a stacktrace from one event to be passed and
displayed by another event.
The special keyword "stacktrace" is to be used to trigger a stack
trace for the event that the histogram trigger is attached to.
echo 'hist:keys=pid:st=stacktrace" > events/sched/sched_waking/trigger
Currently nothing can get access to the "$st" variable above that contains
the stack trace, but that will soon change.
Link: https://lkml.kernel.org/r/20230117152235.856323729@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Ross Zwisler <zwisler@google.com>
Cc: Ching-lin Yu <chinglinyu@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In a previous commit 7433632c9f, buffer, buffer->buffers and
buffer->buffers[cpu] in ring_buffer_wake_waiters() can be NULL,
and thus the related checks are added.
However, in the same call stack, these variables are also used in
ring_buffer_free_read_page():
tracing_buffers_release()
ring_buffer_wake_waiters(iter->array_buffer->buffer)
cpu_buffer = buffer->buffers[cpu] -> Add checks by previous commit
ring_buffer_free_read_page(iter->array_buffer->buffer)
cpu_buffer = buffer->buffers[cpu] -> No check
Thus, to avod possible null-pointer derefernces, the related checks
should be added.
These results are reported by a static tool designed by myself.
Link: https://lkml.kernel.org/r/20230113125501.760324-1-baijiaju1990@gmail.com
Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There's been several times where an event records a function address in
its field and I needed to filter on that address for a specific function
name. It required looking up the function in kallsyms, finding its size,
and doing a compare of "field >= function_start && field < function_end".
But this would change from boot to boot and is unreliable in scripts.
Also, it is useful to have this at boot up, where the addresses will not
be known. For example, on the boot command line:
trace_trigger="initcall_finish.traceoff if func.function == acpi_init"
To implement this, add a ".function" prefix, that will check that the
field is of size long, and the only operations allowed (so far) are "=="
and "!=".
Link: https://lkml.kernel.org/r/20221219183213.916833763@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Reviewed-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Use the 'struct' keyword for a struct's kernel-doc notation and
use the correct function parameter name to eliminate kernel-doc
warnings:
kernel/trace/trace_events_filter.c:136: warning: cannot understand function prototype: 'struct prog_entry '
kerne/trace/trace_events_filter.c:155: warning: Excess function parameter 'when_to_branch' description in 'update_preds'
Also correct some trivial punctuation problems.
Link: https://lkml.kernel.org/r/20230108021238.16398-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
list_for_each_entry_rcu() has built-in RCU and lock checking.
Pass cond argument to list_for_each_entry_rcu() to silence false lockdep
warning when CONFIG_PROVE_RCU_LIST is enabled.
Execute as follow:
[tracing]# echo osnoise > current_tracer
[tracing]# echo 1 > tracing_on
[tracing]# echo 0 > tracing_on
The trace_types_lock is held when osnoise_tracer_stop() or
timerlat_tracer_stop() are called in the non-RCU read side section.
So, pass lockdep_is_held(&trace_types_lock) to silence false lockdep
warning.
Link: https://lkml.kernel.org/r/20221227023036.784337-1-nashuiliang@gmail.com
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: dae181349f ("tracing/osnoise: Support a list of trace_array *tr")
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Chuang Wang <nashuiliang@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently trace_printk() can be used as soon as early_trace_init() is
called from start_kernel(). But if a crash happens, and
"ftrace_dump_on_oops" is set on the kernel command line, all you get will
be:
[ 0.456075] <idle>-0 0dN.2. 347519us : Unknown type 6
[ 0.456075] <idle>-0 0dN.2. 353141us : Unknown type 6
[ 0.456075] <idle>-0 0dN.2. 358684us : Unknown type 6
This is because the trace_printk() event (type 6) hasn't been registered
yet. That gets done via an early_initcall(), which may be early, but not
early enough.
Instead of registering the trace_printk() event (and other ftrace events,
which are not trace events) via an early_initcall(), have them registered at
the same time that trace_printk() can be used. This way, if there is a
crash before early_initcall(), then the trace_printk()s will actually be
useful.
Link: https://lkml.kernel.org/r/20230104161412.019f6c55@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: e725c731e3 ("tracing: Split tracing initialization into two for early initialization")
Reported-by: "Joel Fernandes (Google)" <joel@joelfernandes.org>
Tested-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Setting filters on an ftrace ops results in some memory being allocated
for the filter hashes, which must be freed before the ops can be freed.
This can be done by removing every individual element of the hash by
calling ftrace_set_filter_ip() or ftrace_set_filter_ips() with `remove`
set, but this is somewhat error prone as it's easy to forget to remove
an element.
Make it easier to clean this up by exporting ftrace_free_filter(), which
can be used to clean up all of the filter hashes after an ftrace_ops has
been unregistered.
Using this, fix the ftrace-direct* samples to free hashes prior to being
unloaded. All other code either removes individual filters explicitly or
is built-in and already calls ftrace_free_filter().
Link: https://lkml.kernel.org/r/20230103124912.2948963-3-mark.rutland@arm.com
Cc: stable@vger.kernel.org
Cc: Florent Revest <revest@chromium.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: e1067a07cf ("ftrace/samples: Add module to test multi direct modify interface")
Fixes: 5fae941b9a ("ftrace/samples: Add multi direct interface test module")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pull driver core fixes from Greg KH:
"Here are three small driver and kernel core fixes for 6.2-rc5. They
include:
- potential gadget fixup in do_prlimit
- device property refcount leak fix
- test_async_probe bugfix for reported problem"
* tag 'driver-core-6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
prlimit: do_prlimit needs to have a speculation check
driver core: Fix test_async_probe_init saves device in wrong array
device property: fix of node refcount leak in fwnode_graph_get_next_endpoint()
Pull Kbuild fixes from Masahiro Yamada:
- Hide LDFLAGS_vmlinux from decompressor Makefiles to fix error
messages when GNU Make 4.4 is used.
- Fix 'make modules' build error when CONFIG_DEBUG_INFO_BTF_MODULES=y.
- Fix warnings emitted by GNU Make 4.4 in scripts/kconfig/Makefile.
- Support GNU Make 4.4 for scripts/jobserver-exec.
- Show clearer error message when kernel/gen_kheaders.sh fails due to
missing cpio.
* tag 'kbuild-fixes-v6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kheaders: explicitly validate existence of cpio command
scripts: support GNU make 4.4 in jobserver-exec
kconfig: Update all declared targets
scripts: rpm: make clear that mkspec script contains 4.13 feature
init/Kconfig: fix LOCALVERSION_AUTO help text
kbuild: fix 'make modules' error when CONFIG_DEBUG_INFO_BTF_MODULES=y
kbuild: export top-level LDFLAGS_vmlinux only to scripts/Makefile.vmlinux
init/version-timestamp.c: remove unneeded #include <linux/version.h>
docs: kbuild: remove mention to dropped $(objtree) feature
do_prlimit() adds the user-controlled resource value to a pointer that
will subsequently be dereferenced. In order to help prevent this
codepath from being used as a spectre "gadget" a barrier needs to be
added after checking the range.
Reported-by: Jordy Zomer <jordyzomer@google.com>
Tested-by: Jordy Zomer <jordyzomer@google.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull networking fixes from Jakub Kicinski:
"Including fixes from wireless, bluetooth, bpf and netfilter.
Current release - regressions:
- Revert "net: team: use IFF_NO_ADDRCONF flag to prevent ipv6
addrconf", fix nsna_ping mode of team
- wifi: mt76: fix bugs in Rx queue handling and DMA mapping
- eth: mlx5:
- add missing mutex_unlock in error reporter
- protect global IPsec ASO with a lock
Current release - new code bugs:
- rxrpc: fix wrong error return in rxrpc_connect_call()
Previous releases - regressions:
- bluetooth: hci_sync: fix use of HCI_OP_LE_READ_BUFFER_SIZE_V2
- wifi:
- mac80211: fix crashes on Rx due to incorrect initialization of
rx->link and rx->link_sta
- mac80211: fix bugs in iTXQ conversion - Tx stalls, incorrect
aggregation handling, crashes
- brcmfmac: fix regression for Broadcom PCIe wifi devices
- rndis_wlan: prevent buffer overflow in rndis_query_oid
- netfilter: conntrack: handle tcp challenge acks during connection
reuse
- sched: avoid grafting on htb_destroy_class_offload when destroying
- virtio-net: correctly enable callback during start_xmit, fix stalls
- tcp: avoid the lookup process failing to get sk in ehash table
- ipa: disable ipa interrupt during suspend
- eth: stmmac: enable all safety features by default
Previous releases - always broken:
- bpf:
- fix pointer-leak due to insufficient speculative store bypass
mitigation (Spectre v4)
- skip task with pid=1 in send_signal_common() to avoid a splat
- fix BPF program ID information in BPF_AUDIT_UNLOAD as well as
PERF_BPF_EVENT_PROG_UNLOAD events
- fix potential deadlock in htab_lock_bucket from same bucket
index but different map_locked index
- bluetooth:
- fix a buffer overflow in mgmt_mesh_add()
- hci_qca: fix driver shutdown on closed serdev
- ISO: fix possible circular locking dependency
- CIS: hci_event: fix invalid wait context
- wifi: brcmfmac: fixes for survey dump handling
- mptcp: explicitly specify sock family at subflow creation time
- netfilter: nft_payload: incorrect arithmetics when fetching VLAN
header bits
- tcp: fix rate_app_limited to default to 1
- l2tp: close all race conditions in l2tp_tunnel_register()
- eth: mlx5: fixes for QoS config and eswitch configuration
- eth: enetc: avoid deadlock in enetc_tx_onestep_tstamp()
- eth: stmmac: fix invalid call to mdiobus_get_phy()
Misc:
- ethtool: add netlink attr in rss get reply only if the value is not
empty"
* tag 'net-6.2-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (88 commits)
Revert "Merge branch 'octeontx2-af-CPT'"
tcp: fix rate_app_limited to default to 1
bnxt: Do not read past the end of test names
net: stmmac: enable all safety features by default
octeontx2-af: add mbox to return CPT_AF_FLT_INT info
octeontx2-af: update cpt lf alloc mailbox
octeontx2-af: restore rxc conf after teardown sequence
octeontx2-af: optimize cpt pf identification
octeontx2-af: modify FLR sequence for CPT
octeontx2-af: add mbox for CPT LF reset
octeontx2-af: recover CPT engine when it gets fault
net: dsa: microchip: ksz9477: port map correction in ALU table entry register
selftests/net: toeplitz: fix race on tpacket_v3 block close
net/ulp: use consistent error code when blocking ULP
octeontx2-pf: Fix the use of GFP_KERNEL in atomic context on rt
tcp: avoid the lookup process failing to get sk in ehash table
Revert "net: team: use IFF_NO_ADDRCONF flag to prevent ipv6 addrconf"
MAINTAINERS: add networking entries for Willem
net: sched: gred: prevent races when adding offloads to stats
l2tp: prevent lockdep issue in l2tp_tunnel_register()
...
Pull printk fixes from Petr Mladek:
- Prevent a potential deadlock when configuring kgdb console
- Fix a kernel doc warning
* tag 'printk-for-6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
kernel/printk/printk.c: Fix W=1 kernel-doc warning
tty: serial: kgdboc: fix mutex locking order for configure_kgdboc()
If the cpio command is not available the error emitted by
gen_kheaders.so is not clear as all output of the call to cpio is
discarded:
GNU make 4.4:
GEN kernel/kheaders_data.tar.xz
find: 'standard output': Broken pipe
find: write error
make[2]: *** [kernel/Makefile:157: kernel/kheaders_data.tar.xz] Error 127
make[1]: *** [scripts/Makefile.build:504: kernel] Error 2
GNU make < 4.4:
GEN kernel/kheaders_data.tar.xz
make[2]: *** [kernel/Makefile:157: kernel/kheaders_data.tar.xz] Error 127
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [scripts/Makefile.build:504: kernel] Error 2
Add an explicit check that will trigger a clear message about the issue:
CHK kernel/kheaders_data.tar.xz
./kernel/gen_kheaders.sh: line 17: type: cpio: not found
The other commands executed by gen_kheaders.sh are part of a standard
installation, so they are not checked.
Reported-by: Amy Parker <apark0006@student.cerritos.edu>
Link: https://lore.kernel.org/lkml/CAPOgqxFva=tOuh1UitCSN38+28q3BNXKq19rEsVNPRzRqKqZ+g@mail.gmail.com/
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Daniel Borkmann says:
====================
bpf 2023-01-16
We've added 6 non-merge commits during the last 8 day(s) which contain
a total of 6 files changed, 22 insertions(+), 24 deletions(-).
The main changes are:
1) Mitigate a Spectre v4 leak in unprivileged BPF from speculative
pointer-as-scalar type confusion, from Luis Gerhorst.
2) Fix a splat when pid 1 attaches a BPF program that attempts to
send killing signal to itself, from Hao Sun.
3) Fix BPF program ID information in BPF_AUDIT_UNLOAD as well as
PERF_BPF_EVENT_PROG_UNLOAD events, from Paul Moore.
4) Fix BPF verifier warning triggered from invalid kfunc call in
backtrack_insn, also from Hao Sun.
5) Fix potential deadlock in htab_lock_bucket from same bucket index
but different map_locked index, from Tonghao Zhang.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Fix pointer-leak due to insufficient speculative store bypass mitigation
bpf: hash map, avoid deadlock with suitable hash mask
bpf: remove the do_idr_lock parameter from bpf_prog_free_id()
bpf: restore the ebpf program ID for BPF_AUDIT_UNLOAD and PERF_BPF_EVENT_PROG_UNLOAD
bpf: Skip task with pid=1 in send_signal_common()
bpf: Skip invalid kfunc call in backtrack_insn
====================
Link: https://lore.kernel.org/r/20230116230745.21742-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Several mutexes are taken while setting up console serial ports. In
particular, the tty_port->mutex and @console_mutex are taken:
serial_pnp_probe
serial8250_register_8250_port
uart_add_one_port (locks tty_port->mutex)
uart_configure_port
register_console (locks @console_mutex)
In order to synchronize kgdb's tty_find_polling_driver() with
register_console(), commit 6193bc9084 ("tty: serial: kgdboc:
synchronize tty_find_polling_driver() and register_console()") takes
the @console_mutex. However, this leads to the following call chain
(with locking):
platform_probe
kgdboc_probe
configure_kgdboc (locks @console_mutex)
tty_find_polling_driver
uart_poll_init (locks tty_port->mutex)
uart_set_options
This is clearly deadlock potential due to the reverse lock ordering.
Since uart_set_options() requires holding @console_mutex in order to
serialize early initialization of the serial-console lock, take the
@console_mutex in uart_poll_init() instead of configure_kgdboc().
Since configure_kgdboc() was using @console_mutex for safe traversal
of the console list, change it to use the SRCU iterator instead.
Add comments to uart_set_options() kerneldoc mentioning that it
requires holding @console_mutex (aka the console_list_lock).
Fixes: 6193bc9084 ("tty: serial: kgdboc: synchronize tty_find_polling_driver() and register_console()")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
[pmladek@suse.com: Export console_srcu_read_lock_is_held() to fix build kgdboc as a module.]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230112161213.1434854-1-john.ogness@linutronix.de
Pull module fix from Luis Chamberlain:
"Just one fix for modules by Nick"
* tag 'modules-6.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
kallsyms: Fix scheduling with interrupts disabled in self-test
To mitigate Spectre v4, 2039f26f3a ("bpf: Fix leakage due to
insufficient speculative store bypass mitigation") inserts lfence
instructions after 1) initializing a stack slot and 2) spilling a
pointer to the stack.
However, this does not cover cases where a stack slot is first
initialized with a pointer (subject to sanitization) but then
overwritten with a scalar (not subject to sanitization because
the slot was already initialized). In this case, the second write
may be subject to speculative store bypass (SSB) creating a
speculative pointer-as-scalar type confusion. This allows the
program to subsequently leak the numerical pointer value using,
for example, a branch-based cache side channel.
To fix this, also sanitize scalars if they write a stack slot
that previously contained a pointer. Assuming that pointer-spills
are only generated by LLVM on register-pressure, the performance
impact on most real-world BPF programs should be small.
The following unprivileged BPF bytecode drafts a minimal exploit
and the mitigation:
[...]
// r6 = 0 or 1 (skalar, unknown user input)
// r7 = accessible ptr for side channel
// r10 = frame pointer (fp), to be leaked
//
r9 = r10 # fp alias to encourage ssb
*(u64 *)(r9 - 8) = r10 // fp[-8] = ptr, to be leaked
// lfence added here because of pointer spill to stack.
//
// Ommitted: Dummy bpf_ringbuf_output() here to train alias predictor
// for no r9-r10 dependency.
//
*(u64 *)(r10 - 8) = r6 // fp[-8] = scalar, overwrites ptr
// 2039f26f3a: no lfence added because stack slot was not STACK_INVALID,
// store may be subject to SSB
//
// fix: also add an lfence when the slot contained a ptr
//
r8 = *(u64 *)(r9 - 8)
// r8 = architecturally a scalar, speculatively a ptr
//
// leak ptr using branch-based cache side channel:
r8 &= 1 // choose bit to leak
if r8 == 0 goto SLOW // no mispredict
// architecturally dead code if input r6 is 0,
// only executes speculatively iff ptr bit is 1
r8 = *(u64 *)(r7 + 0) # encode bit in cache (0: slow, 1: fast)
SLOW:
[...]
After running this, the program can time the access to *(r7 + 0) to
determine whether the chosen pointer bit was 0 or 1. Repeat this 64
times to recover the whole address on amd64.
In summary, sanitization can only be skipped if one scalar is
overwritten with another scalar. Scalar-confusion due to speculative
store bypass can not lead to invalid accesses because the pointer
bounds deducted during verification are enforced using branchless
logic. See 979d63d50c ("bpf: prevent out of bounds speculation on
pointer arithmetic") for details.
Do not make the mitigation depend on !env->allow_{uninit_stack,ptr_leaks}
because speculative leaks are likely unexpected if these were enabled.
For example, leaking the address to a protected log file may be acceptable
while disabling the mitigation might unintentionally leak the address
into the cached-state of a map that is accessible to unprivileged
processes.
Fixes: 2039f26f3a ("bpf: Fix leakage due to insufficient speculative store bypass mitigation")
Signed-off-by: Luis Gerhorst <gerhorst@cs.fau.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Henriette Hofmeier <henriette.hofmeier@rub.de>
Link: https://lore.kernel.org/bpf/edc95bad-aada-9cfc-ffe2-fa9bb206583c@cs.fau.de
Link: https://lore.kernel.org/bpf/20230109150544.41465-1-gerhorst@cs.fau.de
Pull timer doc fixes from Ingo Molnar:
- Fix various DocBook formatting errors in kernel/time/ that generated
(justified) warnings during a kernel-doc build.
* tag 'timers-urgent-2023-01-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time: Fix various kernel-doc problems
Pull scheduler fixes from Ingo Molnar:
- Fix scheduler frequency invariance bug related to overly long
tickless periods triggering an integer overflow and disabling the
feature.
- Fix use-after-free bug in dup_user_cpus_ptr().
- Fix do_set_cpus_allowed() deadlock scenarios related to calling
kfree() with the pi_lock held. NOTE: the rcu_free() is the 'lazy'
solution here - we looked at patches to free the structure after the
pi_lock got dropped, but that looked quite a bit messier - and none
of this is truly performance critical. We can revisit this if it's
too lazy of a solution ...
* tag 'sched-urgent-2023-01-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Use kfree_rcu() in do_set_cpus_allowed()
sched/core: Fix use-after-free bug in dup_user_cpus_ptr()
sched/core: Fix arch_scale_freq_tick() on tickless systems
Pull xtensa fixes from Max Filippov:
- fix xtensa allmodconfig build broken by the kcsan test
- drop unused members of struct thread_struct
* tag 'xtensa-20230110' of https://github.com/jcmvbkbc/linux-xtensa:
xtensa: drop unused members of struct thread_struct
kcsan: test: don't put the expect array on the stack
When changing the ebpf program put() routines to support being called
from within IRQ context the program ID was reset to zero prior to
calling the perf event and audit UNLOAD record generators, which
resulted in problems as the ebpf program ID was bogus (always zero).
This patch addresses this problem by removing an unnecessary call to
bpf_prog_free_id() in __bpf_prog_offload_destroy() and adjusting
__bpf_prog_put() to only call bpf_prog_free_id() after audit and perf
have finished their bpf program unload tasks in
bpf_prog_put_deferred(). For the record, no one can determine, or
remember, why it was necessary to free the program ID, and remove it
from the IDR, prior to executing bpf_prog_put_deferred();
regardless, both Stanislav and Alexei agree that the approach in this
patch should be safe.
It is worth noting that when moving the bpf_prog_free_id() call, the
do_idr_lock parameter was forced to true as the ebpf devs determined
this was the correct as the do_idr_lock should always be true. The
do_idr_lock parameter will be removed in a follow-up patch, but it
was kept here to keep the patch small in an effort to ease any stable
backports.
I also modified the bpf_audit_prog() logic used to associate the
AUDIT_BPF record with other associated records, e.g. @ctx != NULL.
Instead of keying off the operation, it now keys off the execution
context, e.g. '!in_irg && !irqs_disabled()', which is much more
appropriate and should help better connect the UNLOAD operations with
the associated audit state (other audit records).
Cc: stable@vger.kernel.org
Fixes: d809e134be ("bpf: Prepare bpf_prog_put() to be called from irq context.")
Reported-by: Burn Alting <burn.alting@iinet.net.au>
Reported-by: Jiri Olsa <olsajiri@gmail.com>
Suggested-by: Stanislav Fomichev <sdf@google.com>
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230106154400.74211-1-paul@paul-moore.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit 851a723e45 ("sched: Always clear user_cpus_ptr in
do_set_cpus_allowed()") may call kfree() if user_cpus_ptr was previously
set. Unfortunately, some of the callers of do_set_cpus_allowed()
may have pi_lock held when calling it. So the following splats may be
printed especially when running with a PREEMPT_RT kernel:
WARNING: possible circular locking dependency detected
BUG: sleeping function called from invalid context
To avoid these problems, kfree_rcu() is used instead. An internal
cpumask_rcuhead union is created for the sole purpose of facilitating
the use of kfree_rcu() to free the cpumask.
Since user_cpus_ptr is not being used in non-SMP configs, the newly
introduced alloc_user_cpus_ptr() helper will return NULL in this case
and sched_setaffinity() is modified to handle this special case.
Fixes: 851a723e45 ("sched: Always clear user_cpus_ptr in do_set_cpus_allowed()")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221231041120.440785-3-longman@redhat.com
Since commit 07ec77a1d4 ("sched: Allow task CPU affinity to be
restricted on asymmetric systems"), the setting and clearing of
user_cpus_ptr are done under pi_lock for arm64 architecture. However,
dup_user_cpus_ptr() accesses user_cpus_ptr without any lock
protection. Since sched_setaffinity() can be invoked from another
process, the process being modified may be undergoing fork() at
the same time. When racing with the clearing of user_cpus_ptr in
__set_cpus_allowed_ptr_locked(), it can lead to user-after-free and
possibly double-free in arm64 kernel.
Commit 8f9ea86fdf ("sched: Always preserve the user requested
cpumask") fixes this problem as user_cpus_ptr, once set, will never
be cleared in a task's lifetime. However, this bug was re-introduced
in commit 851a723e45 ("sched: Always clear user_cpus_ptr in
do_set_cpus_allowed()") which allows the clearing of user_cpus_ptr in
do_set_cpus_allowed(). This time, it will affect all arches.
Fix this bug by always clearing the user_cpus_ptr of the newly
cloned/forked task before the copying process starts and check the
user_cpus_ptr state of the source task under pi_lock.
Note to stable, this patch won't be applicable to stable releases.
Just copy the new dup_user_cpus_ptr() function over.
Fixes: 07ec77a1d4 ("sched: Allow task CPU affinity to be restricted on asymmetric systems")
Fixes: 851a723e45 ("sched: Always clear user_cpus_ptr in do_set_cpus_allowed()")
Reported-by: David Wang 王标 <wangbiao3@xiaomi.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20221231041120.440785-2-longman@redhat.com
In order for the scheduler to be frequency invariant we measure the
ratio between the maximum CPU frequency and the actual CPU frequency.
During long tickless periods of time the calculations that keep track
of that might overflow, in the function scale_freq_tick():
if (check_shl_overflow(acnt, 2*SCHED_CAPACITY_SHIFT, &acnt))
goto error;
eventually forcing the kernel to disable the feature for all CPUs,
and show the warning message:
"Scheduler frequency invariance went wobbly, disabling!".
Let's avoid that by limiting the frequency invariant calculations
to CPUs with regular tick.
Fixes: e2b0d619b4 ("x86, sched: check for counters overflow in frequency invariant accounting")
Suggested-by: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Signed-off-by: Yair Podemsky <ypodemsk@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Acked-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Link: https://lore.kernel.org/r/20221130125121.34407-1-ypodemsk@redhat.com
The following kernel panic can be triggered when a task with pid=1 attaches
a prog that attempts to send killing signal to itself, also see [1] for more
details:
Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
CPU: 3 PID: 1 Comm: systemd Not tainted 6.1.0-09652-g59fe41b5255f #148
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x100/0x178 lib/dump_stack.c:106
panic+0x2c4/0x60f kernel/panic.c:275
do_exit.cold+0x63/0xe4 kernel/exit.c:789
do_group_exit+0xd4/0x2a0 kernel/exit.c:950
get_signal+0x2460/0x2600 kernel/signal.c:2858
arch_do_signal_or_restart+0x78/0x5d0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203
__syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296
do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x63/0xcd
So skip task with pid=1 in bpf_send_signal_common() to avoid the panic.
[1] https://lore.kernel.org/bpf/20221222043507.33037-1-sunhao.th@gmail.com
Signed-off-by: Hao Sun <sunhao.th@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230106084838.12690-1-sunhao.th@gmail.com
The verifier skips invalid kfunc call in check_kfunc_call(), which
would be captured in fixup_kfunc_call() if such insn is not eliminated
by dead code elimination. However, this can lead to the following
warning in backtrack_insn(), also see [1]:
------------[ cut here ]------------
verifier backtracking bug
WARNING: CPU: 6 PID: 8646 at kernel/bpf/verifier.c:2756 backtrack_insn
kernel/bpf/verifier.c:2756
__mark_chain_precision kernel/bpf/verifier.c:3065
mark_chain_precision kernel/bpf/verifier.c:3165
adjust_reg_min_max_vals kernel/bpf/verifier.c:10715
check_alu_op kernel/bpf/verifier.c:10928
do_check kernel/bpf/verifier.c:13821 [inline]
do_check_common kernel/bpf/verifier.c:16289
[...]
So make backtracking conservative with this by returning ENOTSUPP.
[1] https://lore.kernel.org/bpf/CACkBjsaXNceR8ZjkLG=dT3P=4A8SBsg0Z5h5PWLryF5=ghKq=g@mail.gmail.com/
Reported-by: syzbot+4da3ff23081bafe74fc2@syzkaller.appspotmail.com
Signed-off-by: Hao Sun <sunhao.th@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230104014709.9375-1-sunhao.th@gmail.com
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf, wifi, and netfilter.
Current release - regressions:
- bpf: fix nullness propagation for reg to reg comparisons, avoid
null-deref
- inet: control sockets should not use current thread task_frag
- bpf: always use maximal size for copy_array()
- eth: bnxt_en: don't link netdev to a devlink port for VFs
Current release - new code bugs:
- rxrpc: fix a couple of potential use-after-frees
- netfilter: conntrack: fix IPv6 exthdr error check
- wifi: iwlwifi: fw: skip PPAG for JF, avoid FW crashes
- eth: dsa: qca8k: various fixes for the in-band register access
- eth: nfp: fix schedule in atomic context when sync mc address
- eth: renesas: rswitch: fix getting mac address from device tree
- mobile: ipa: use proper endpoint mask for suspend
Previous releases - regressions:
- tcp: add TIME_WAIT sockets in bhash2, fix regression caught by
Jiri / python tests
- net: tc: don't intepret cls results when asked to drop, fix
oob-access
- vrf: determine the dst using the original ifindex for multicast
- eth: bnxt_en:
- fix XDP RX path if BPF adjusted packet length
- fix HDS (header placement) and jumbo thresholds for RX packets
- eth: ice: xsk: do not use xdp_return_frame() on tx_buf->raw_buf,
avoid memory corruptions
Previous releases - always broken:
- ulp: prevent ULP without clone op from entering the LISTEN status
- veth: fix race with AF_XDP exposing old or uninitialized
descriptors
- bpf:
- pull before calling skb_postpull_rcsum() (fix checksum support
and avoid a WARN())
- fix panic due to wrong pageattr of im->image (when livepatch and
kretfunc coexist)
- keep a reference to the mm, in case the task is dead
- mptcp: fix deadlock in fastopen error path
- netfilter:
- nf_tables: perform type checking for existing sets
- nf_tables: honor set timeout and garbage collection updates
- ipset: fix hash:net,port,net hang with /0 subnet
- ipset: avoid hung task warning when adding/deleting entries
- selftests: net:
- fix cmsg_so_mark.sh test hang on non-x86 systems
- fix the arp_ndisc_evict_nocarrier test for IPv6
- usb: rndis_host: secure rndis_query check against int overflow
- eth: r8169: fix dmar pte write access during suspend/resume with
WOL
- eth: lan966x: fix configuration of the PCS
- eth: sparx5: fix reading of the MAC address
- eth: qed: allow sleep in qed_mcp_trace_dump()
- eth: hns3:
- fix interrupts re-initialization after VF FLR
- fix handling of promisc when MAC addr table gets full
- refine the handling for VF heartbeat
- eth: mlx5:
- properly handle ingress QinQ-tagged packets on VST
- fix io_eq_size and event_eq_size params validation on big endian
- fix RoCE setting at HCA level if not supported at all
- don't turn CQE compression on by default for IPoIB
- eth: ena:
- fix toeplitz initial hash key value
- account for the number of XDP-processed bytes in interface stats
- fix rx_copybreak value update
Misc:
- ethtool: harden phy stat handling against buggy drivers
- docs: netdev: convert maintainer's doc from FAQ to a normal
document"
* tag 'net-6.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (112 commits)
caif: fix memory leak in cfctrl_linkup_request()
inet: control sockets should not use current thread task_frag
net/ulp: prevent ULP without clone op from entering the LISTEN status
qed: allow sleep in qed_mcp_trace_dump()
MAINTAINERS: Update maintainers for ptp_vmw driver
usb: rndis_host: Secure rndis_query check against int overflow
net: dpaa: Fix dtsec check for PCS availability
octeontx2-pf: Fix lmtst ID used in aura free
drivers/net/bonding/bond_3ad: return when there's no aggregator
netfilter: ipset: Rework long task execution when adding/deleting entries
netfilter: ipset: fix hash:net,port,net hang with /0 subnet
net: sparx5: Fix reading of the MAC address
vxlan: Fix memory leaks in error path
net: sched: htb: fix htb_classify() kernel-doc
net: sched: cbq: dont intepret cls results when asked to drop
net: sched: atm: dont intepret cls results when asked to drop
dt-bindings: net: marvell,orion-mdio: Fix examples
dt-bindings: net: sun8i-emac: Add phy-supply property
net: ipa: use proper endpoint mask for suspend
selftests: net: return non-zero for failures reported in arp_ndisc_evict_nocarrier
...
Clean up kernel-doc complaints about function names and non-kernel-doc
comments in kernel/time/. Fixes these warnings:
kernel/time/time.c:479: warning: expecting prototype for set_normalized_timespec(). Prototype was for set_normalized_timespec64() instead
kernel/time/time.c:553: warning: expecting prototype for msecs_to_jiffies(). Prototype was for __msecs_to_jiffies() instead
kernel/time/timekeeping.c:1595: warning: contents before sections
kernel/time/timekeeping.c:1705: warning: This comment starts with '/**', but isn't a kernel-doc comment.
* We have three kinds of time sources to use for sleep time
kernel/time/timekeeping.c:1726: warning: This comment starts with '/**', but isn't a kernel-doc comment.
* 1) can be determined whether to use or not only when doing
kernel/time/tick-oneshot.c:21: warning: missing initial short description on line:
* tick_program_event
kernel/time/tick-oneshot.c:107: warning: expecting prototype for tick_check_oneshot_mode(). Prototype was for tick_oneshot_mode_active() instead
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230103032849.12723-1-rdunlap@infradead.org
Size of the 'expect' array in the __report_matches is 1536 bytes, which
is exactly the default frame size warning limit of the xtensa
architecture.
As a result allmodconfig xtensa kernel builds with the gcc that does not
support the compiler plugins (which otherwise would push the said
warning limit to 2K) fail with the following message:
kernel/kcsan/kcsan_test.c:257:1: error: the frame size of 1680 bytes
is larger than 1536 bytes
Fix it by dynamically allocating the 'expect' array.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Marco Elver <elver@google.com>
Pull perf fixes from Borislav Petkov:
- Pass only an initialized perf event attribute to the LSM hook
- Fix a use-after-free on the perf syscall's error path
- A potential integer overflow fix in amd_core_pmu_init()
- Fix the cgroup events tracking after the context handling rewrite
- Return the proper value from the inherit_event() function on error
* tag 'perf_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Call LSM hook after copying perf_event_attr
perf: Fix use-after-free in error path
perf/x86/amd: fix potential integer overflow on shift of a int
perf/core: Fix cgroup events tracking
perf core: Return error pointer if inherit_event() fails to find pmu_ctx
Pull locking fixes from Borislav Petkov:
- Prevent the leaking of a debug timer in futex_waitv()
- A preempt-RT mutex locking fix, adding the proper acquire semantics
* tag 'locking_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Fix futex_waitv() hrtimer debug object leak on kcalloc error
rtmutex: Add acquire semantics for rtmutex lock acquisition slow path
Fix the system crash that happens when a task iterator travel through
vma of tasks.
In task iterators, we used to access mm by following the pointer on
the task_struct; however, the death of a task will clear the pointer,
even though we still hold the task_struct. That can cause an
unexpected crash for a null pointer when an iterator is visiting a
task that dies during the visit. Keeping a reference of mm on the
iterator ensures we always have a valid pointer to mm.
Co-developed-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Reported-by: Nathan Slingerland <slinger@meta.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221216221855.4122288-2-kuifeng@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
