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Xu writes:
FPGA Manager changes for 6.1-final
Intel m10 bmc secure update
- Russ's change fixes Kconfig dependencies
All patches have been reviewed on the mailing list, and have been in the
last linux-next releases (as part of our for-6.1 branch)
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
* tag 'fpga-for-6.1-final' of git://git.kernel.org/pub/scm/linux/kernel/git/fpga/linux-fpga:
fpga: m10bmc-sec: Fix kconfig dependencies
The secure update driver depends on the firmware-upload functionality of
the firmware-loader. The firmware-loader is carried in the firmware-class
driver which is enabled with the tristate CONFIG_FW_LOADER option. The
firmware-upload functionality is included in the firmware-class driver if
the bool FW_UPLOAD config is set.
The current dependency statement, "depends on FW_UPLOAD", is not adequate
because it does not implicitly turn on FW_LOADER. Instead of adding a
dependency, follow the convention used by drivers that require the
FW_LOADER_USER_HELPER functionality of the firmware-loader by using
select for both FW_LOADER and FW_UPLOAD.
Fixes: bdf86d0e6ca3 ("fpga: m10bmc-sec: create max10 bmc secure update")
Reported-by: kernel test robot <lkp@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20221115001127.289890-1-russell.h.weight@intel.com
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Pull tracing/probes fixes from Steven Rostedt:
- Fix possible NULL pointer dereference on trace_event_file in
kprobe_event_gen_test_exit()
- Fix NULL pointer dereference for trace_array in
kprobe_event_gen_test_exit()
- Fix memory leak of filter string for eprobes
- Fix a possible memory leak in rethook_alloc()
- Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case which
can cause a possible use-after-free
- Fix warning in eprobe filter creation
- Fix eprobe filter creation as it picked the wrong event for the
fields
* tag 'trace-probes-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/eprobe: Fix eprobe filter to make a filter correctly
tracing/eprobe: Fix warning in filter creation
kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case
rethook: fix a potential memleak in rethook_alloc()
tracing/eprobe: Fix memory leak of filter string
tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit()
tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit()
Pull tracing fixes from Steven Rostedt:
- Fix polling to block on watermark like the reads do, as user space
applications get confused when the select says read is available, and
then the read blocks
- Fix accounting of ring buffer dropped pages as it is what is used to
determine if the buffer is empty or not
- Fix memory leak in tracing_read_pipe()
- Fix struct trace_array warning about being declared in parameters
- Fix accounting of ftrace pages used in output at start up.
- Fix allocation of dyn_ftrace pages by subtracting one from order
instead of diving it by 2
- Static analyzer found a case were a pointer being used outside of a
NULL check (rb_head_page_deactivate())
- Fix possible NULL pointer dereference if kstrdup() fails in
ftrace_add_mod()
- Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event()
- Fix bad pointer dereference in register_synth_event() on error path
- Remove unused __bad_type_size() method
- Fix possible NULL pointer dereference of entry in list 'tr->err_log'
- Fix NULL pointer deference race if eprobe is called before the event
setup
* tag 'trace-v6.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Fix race where eprobes can be called before the event
tracing: Fix potential null-pointer-access of entry in list 'tr->err_log'
tracing: Remove unused __bad_type_size() method
tracing: Fix wild-memory-access in register_synth_event()
tracing: Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event()
ftrace: Fix null pointer dereference in ftrace_add_mod()
ring_buffer: Do not deactivate non-existant pages
ftrace: Optimize the allocation for mcount entries
ftrace: Fix the possible incorrect kernel message
tracing: Fix warning on variable 'struct trace_array'
tracing: Fix memory leak in tracing_read_pipe()
ring-buffer: Include dropped pages in counting dirty patches
tracing/ring-buffer: Have polling block on watermark
Since the eprobe filter was defined based on the eprobe's trace event
itself, it doesn't work correctly. Use the original trace event of
the eprobe when making the filter so that the filter works correctly.
Without this fix:
# echo 'e syscalls/sys_enter_openat \
flags_rename=$flags:u32 if flags < 1000' >> dynamic_events
# echo 1 > events/eprobes/sys_enter_openat/enable
[ 114.551550] event trace: Could not enable event sys_enter_openat
-bash: echo: write error: Invalid argument
With this fix:
# echo 'e syscalls/sys_enter_openat \
flags_rename=$flags:u32 if flags < 1000' >> dynamic_events
# echo 1 > events/eprobes/sys_enter_openat/enable
# tail trace
cat-241 [000] ...1. 266.498449: sys_enter_openat: (syscalls.sys_enter_openat) flags_rename=0
cat-242 [000] ...1. 266.977640: sys_enter_openat: (syscalls.sys_enter_openat) flags_rename=0
Link: https://lore.kernel.org/all/166823166395.1385292.8931770640212414483.stgit@devnote3/
Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support")
Reported-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Tested-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Pull more random number generator updates from Jason Donenfeld:
"This time with some large scale treewide cleanups.
The intent of this pull is to clean up the way callers fetch random
integers. The current rules for doing this right are:
- If you want a secure or an insecure random u64, use get_random_u64()
- If you want a secure or an insecure random u32, use get_random_u32()
The old function prandom_u32() has been deprecated for a while
now and is just a wrapper around get_random_u32(). Same for
get_random_int().
- If you want a secure or an insecure random u16, use get_random_u16()
- If you want a secure or an insecure random u8, use get_random_u8()
- If you want secure or insecure random bytes, use get_random_bytes().
The old function prandom_bytes() has been deprecated for a while
now and has long been a wrapper around get_random_bytes()
- If you want a non-uniform random u32, u16, or u8 bounded by a
certain open interval maximum, use prandom_u32_max()
I say "non-uniform", because it doesn't do any rejection sampling
or divisions. Hence, it stays within the prandom_*() namespace, not
the get_random_*() namespace.
I'm currently investigating a "uniform" function for 6.2. We'll see
what comes of that.
By applying these rules uniformly, we get several benefits:
- By using prandom_u32_max() with an upper-bound that the compiler
can prove at compile-time is ≤65536 or ≤256, internally
get_random_u16() or get_random_u8() is used, which wastes fewer
batched random bytes, and hence has higher throughput.
- By using prandom_u32_max() instead of %, when the upper-bound is
not a constant, division is still avoided, because
prandom_u32_max() uses a faster multiplication-based trick instead.
- By using get_random_u16() or get_random_u8() in cases where the
return value is intended to indeed be a u16 or a u8, we waste fewer
batched random bytes, and hence have higher throughput.
This series was originally done by hand while I was on an airplane
without Internet. Later, Kees and I worked on retroactively figuring
out what could be done with Coccinelle and what had to be done
manually, and then we split things up based on that.
So while this touches a lot of files, the actual amount of code that's
hand fiddled is comfortably small"
* tag 'random-6.1-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
prandom: remove unused functions
treewide: use get_random_bytes() when possible
treewide: use get_random_u32() when possible
treewide: use get_random_{u8,u16}() when possible, part 2
treewide: use get_random_{u8,u16}() when possible, part 1
treewide: use prandom_u32_max() when possible, part 2
treewide: use prandom_u32_max() when possible, part 1
Pull x86 fixes from Borislav Petkov:
- Do not hold fpregs lock when inheriting FPU permissions because the
fpregs lock disables preemption on RT but fpu_inherit_perms() does
spin_lock_irq(), which, on RT, uses rtmutexes and they need to be
preemptible.
- Check the page offset and the length of the data supplied by
userspace for overflow when specifying a set of pages to add to an
SGX enclave
* tag 'x86_urgent_for_v6.1_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu: Drop fpregs lock before inheriting FPU permissions
x86/sgx: Add overflow check in sgx_validate_offset_length()
The flag that tells the event to call its triggers after reading the event
is set for eprobes after the eprobe is enabled. This leads to a race where
the eprobe may be triggered at the beginning of the event where the record
information is NULL. The eprobe then dereferences the NULL record causing
a NULL kernel pointer bug.
Test for a NULL record to keep this from happening.
Link: https://lore.kernel.org/linux-trace-kernel/20221116192552.1066630-1-rafaelmendsr@gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20221117214249.2addbe10@gandalf.local.home
Cc: Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 7491e2c442781 ("tracing: Add a probe that attaches to trace events")
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reported-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The filter pointer (filterp) passed to create_filter() function must be a
pointer that references a NULL pointer, otherwise, we get a warning when
adding a filter option to the event probe:
root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core sched/sched_stat_runtime \
runtime=$runtime:u32 if cpu < 4' >> dynamic_events
[ 5034.340439] ------------[ cut here ]------------
[ 5034.341258] WARNING: CPU: 0 PID: 223 at kernel/trace/trace_events_filter.c:1939 create_filter+0x1db/0x250
[...] stripped
[ 5034.345518] RIP: 0010:create_filter+0x1db/0x250
[...] stripped
[ 5034.351604] Call Trace:
[ 5034.351803] <TASK>
[ 5034.351959] ? process_preds+0x1b40/0x1b40
[ 5034.352241] ? rcu_read_lock_bh_held+0xd0/0xd0
[ 5034.352604] ? kasan_set_track+0x29/0x40
[ 5034.352904] ? kasan_save_alloc_info+0x1f/0x30
[ 5034.353264] create_event_filter+0x38/0x50
[ 5034.353573] __trace_eprobe_create+0x16f4/0x1d20
[ 5034.353964] ? eprobe_dyn_event_release+0x360/0x360
[ 5034.354363] ? mark_held_locks+0xa6/0xf0
[ 5034.354684] ? _raw_spin_unlock_irqrestore+0x35/0x60
[ 5034.355105] ? trace_hardirqs_on+0x41/0x120
[ 5034.355417] ? _raw_spin_unlock_irqrestore+0x35/0x60
[ 5034.355751] ? __create_object+0x5b7/0xcf0
[ 5034.356027] ? lock_is_held_type+0xaf/0x120
[ 5034.356362] ? rcu_read_lock_bh_held+0xb0/0xd0
[ 5034.356716] ? rcu_read_lock_bh_held+0xd0/0xd0
[ 5034.357084] ? kasan_set_track+0x29/0x40
[ 5034.357411] ? kasan_save_alloc_info+0x1f/0x30
[ 5034.357715] ? __kasan_kmalloc+0xb8/0xc0
[ 5034.357985] ? write_comp_data+0x2f/0x90
[ 5034.358302] ? __sanitizer_cov_trace_pc+0x25/0x60
[ 5034.358691] ? argv_split+0x381/0x460
[ 5034.358949] ? write_comp_data+0x2f/0x90
[ 5034.359240] ? eprobe_dyn_event_release+0x360/0x360
[ 5034.359620] trace_probe_create+0xf6/0x110
[ 5034.359940] ? trace_probe_match_command_args+0x240/0x240
[ 5034.360376] eprobe_dyn_event_create+0x21/0x30
[ 5034.360709] create_dyn_event+0xf3/0x1a0
[ 5034.360983] trace_parse_run_command+0x1a9/0x2e0
[ 5034.361297] ? dyn_event_release+0x500/0x500
[ 5034.361591] dyn_event_write+0x39/0x50
[ 5034.361851] vfs_write+0x311/0xe50
[ 5034.362091] ? dyn_event_seq_next+0x40/0x40
[ 5034.362376] ? kernel_write+0x5b0/0x5b0
[ 5034.362637] ? write_comp_data+0x2f/0x90
[ 5034.362937] ? __sanitizer_cov_trace_pc+0x25/0x60
[ 5034.363258] ? ftrace_syscall_enter+0x544/0x840
[ 5034.363563] ? write_comp_data+0x2f/0x90
[ 5034.363837] ? __sanitizer_cov_trace_pc+0x25/0x60
[ 5034.364156] ? write_comp_data+0x2f/0x90
[ 5034.364468] ? write_comp_data+0x2f/0x90
[ 5034.364770] ksys_write+0x158/0x2a0
[ 5034.365022] ? __ia32_sys_read+0xc0/0xc0
[ 5034.365344] __x64_sys_write+0x7c/0xc0
[ 5034.365669] ? syscall_enter_from_user_mode+0x53/0x70
[ 5034.366084] do_syscall_64+0x60/0x90
[ 5034.366356] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[ 5034.366767] RIP: 0033:0x7ff0b43938f3
[...] stripped
[ 5034.371892] </TASK>
[ 5034.374720] ---[ end trace 0000000000000000 ]---
Link: https://lore.kernel.org/all/20221108202148.1020111-1-rafaelmendsr@gmail.com/
Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support")
Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Pull more perf tools updates from Arnaldo Carvalho de Melo:
- Use BPF CO-RE (Compile Once, Run Everywhere) to support old kernels
when using bperf (perf BPF based counters) with cgroups.
- Support HiSilicon PCIe Performance Monitoring Unit (PMU), that
monitors bandwidth, latency, bus utilization and buffer occupancy.
Documented in Documentation/admin-guide/perf/hisi-pcie-pmu.rst.
- User space tasks can migrate between CPUs, so when tracing selected
CPUs, system-wide sideband is still needed, fix it in the setup of
Intel PT on hybrid systems.
- Fix metricgroups title message in 'perf list', it should state that
the metrics groups are to be used with the '-M' option, not '-e'.
- Sync the msr-index.h copy with the kernel sources, adding support for
using "AMD64_TSC_RATIO" in filter expressions in 'perf trace' as well
as decoding it when printing the MSR tracepoint arguments.
- Fix program header size and alignment when generating a JIT ELF in
'perf inject'.
- Add multiple new Intel PT 'perf test' entries, including a jitdump
one.
- Fix the 'perf test' entries for 'perf stat' CSV and JSON output when
running on PowerPC due to an invalid topology number in that arch.
- Fix the 'perf test' for arm_coresight failures on the ARM Juno
system.
- Fix the 'perf test' attr entry for PERF_FORMAT_LOST, adding this
option to the or expression expected in the intercepted
perf_event_open() syscall.
- Add missing condition flags ('hs', 'lo', 'vc', 'vs') for arm64 in the
'perf annotate' asm parser.
- Fix 'perf mem record -C' option processing, it was being chopped up
when preparing the underlying 'perf record -e mem-events' and thus
being ignored, requiring using '-- -C CPUs' as a workaround.
- Improvements and tidy ups for 'perf test' shell infra.
- Fix Intel PT information printing segfault in uClibc, where a NULL
format was being passed to fprintf.
* tag 'perf-tools-for-v6.1-2-2022-10-16' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (23 commits)
tools arch x86: Sync the msr-index.h copy with the kernel sources
perf auxtrace arm64: Add support for parsing HiSilicon PCIe Trace packet
perf auxtrace arm64: Add support for HiSilicon PCIe Tune and Trace device driver
perf auxtrace arm: Refactor event list iteration in auxtrace_record__init()
perf tests stat+json_output: Include sanity check for topology
perf tests stat+csv_output: Include sanity check for topology
perf intel-pt: Fix system_wide dummy event for hybrid
perf intel-pt: Fix segfault in intel_pt_print_info() with uClibc
perf test: Fix attr tests for PERF_FORMAT_LOST
perf test: test_intel_pt.sh: Add 9 tests
perf inject: Fix GEN_ELF_TEXT_OFFSET for jit
perf test: test_intel_pt.sh: Add jitdump test
perf test: test_intel_pt.sh: Tidy some alignment
perf test: test_intel_pt.sh: Print a message when skipping kernel tracing
perf test: test_intel_pt.sh: Tidy some perf record options
perf test: test_intel_pt.sh: Fix return checking again
perf: Skip and warn on unknown format 'configN' attrs
perf list: Fix metricgroups title message
perf mem: Fix -C option behavior for perf mem record
perf annotate: Add missing condition flags for arm64
...
With no callers left of prandom_u32() and prandom_bytes(), as well as
get_random_int(), remove these deprecated wrappers, in favor of
get_random_u32() and get_random_bytes().
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Pull scheduler fixes from Borislav Petkov:
- Fix a small race on the task's exit path where there's a
misunderstanding whether the task holds rq->lock or not
- Prevent processes from getting killed when using deprecated or
unknown rseq ABI flags in order to be able to fuzz the rseq() syscall
with syzkaller
* tag 'sched_urgent_for_v6.1_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix race in task_call_func()
rseq: Use pr_warn_once() when deprecated/unknown ABI flags are encountered
Mike Galbraith reported the following against an old fork of preempt-rt
but the same issue also applies to the current preempt-rt tree.
BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: systemd
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
Preemption disabled at:
fpu_clone
CPU: 6 PID: 1 Comm: systemd Tainted: G E (unreleased)
Call Trace:
<TASK>
dump_stack_lvl
? fpu_clone
__might_resched
rt_spin_lock
fpu_clone
? copy_thread
? copy_process
? shmem_alloc_inode
? kmem_cache_alloc
? kernel_clone
? __do_sys_clone
? do_syscall_64
? __x64_sys_rt_sigprocmask
? syscall_exit_to_user_mode
? do_syscall_64
? syscall_exit_to_user_mode
? do_syscall_64
? syscall_exit_to_user_mode
? do_syscall_64
? exc_page_fault
? entry_SYSCALL_64_after_hwframe
</TASK>
Mike says:
The splat comes from fpu_inherit_perms() being called under fpregs_lock(),
and us reaching the spin_lock_irq() therein due to fpu_state_size_dynamic()
returning true despite static key __fpu_state_size_dynamic having never
been enabled.
Mike's assessment looks correct. fpregs_lock on a PREEMPT_RT kernel disables
preemption so calling spin_lock_irq() in fpu_inherit_perms() is unsafe. This
problem exists since commit
9e798e9aa14c ("x86/fpu: Prepare fpu_clone() for dynamically enabled features").
Even though the original bug report should not have enabled the paths at
all, the bug still exists.
fpregs_lock is necessary when editing the FPU registers or a task's FP
state but it is not necessary for fpu_inherit_perms(). The only write
of any FP state in fpu_inherit_perms() is for the new child which is
not running yet and cannot context switch or be borrowed by a kernel
thread yet. Hence, fpregs_lock is not protecting anything in the new
child until clone() completes and can be dropped earlier. The siglock
still needs to be acquired by fpu_inherit_perms() as the read of the
parent's permissions has to be serialised.
[ bp: Cleanup splat. ]
Fixes: 9e798e9aa14c ("x86/fpu: Prepare fpu_clone() for dynamically enabled features")
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20221110124400.zgymc2lnwqjukgfh@techsingularity.net