fa25f28ef2cef19bc9ffeb827b8ecbf48af7f892
36770 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Steven Rostedt (VMware)
|
1e3bac71c5 |
tracing/histogram: Rename "cpu" to "common_cpu"
Currently the histogram logic allows the user to write "cpu" in as an
event field, and it will record the CPU that the event happened on.
The problem with this is that there's a lot of events that have "cpu"
as a real field, and using "cpu" as the CPU it ran on, makes it
impossible to run histograms on the "cpu" field of events.
For example, if I want to have a histogram on the count of the
workqueue_queue_work event on its cpu field, running:
># echo 'hist:keys=cpu' > events/workqueue/workqueue_queue_work/trigger
Gives a misleading and wrong result.
Change the command to "common_cpu" as no event should have "common_*"
fields as that's a reserved name for fields used by all events. And
this makes sense here as common_cpu would be a field used by all events.
Now we can even do:
># echo 'hist:keys=common_cpu,cpu if cpu < 100' > events/workqueue/workqueue_queue_work/trigger
># cat events/workqueue/workqueue_queue_work/hist
# event histogram
#
# trigger info: hist:keys=common_cpu,cpu:vals=hitcount:sort=hitcount:size=2048 if cpu < 100 [active]
#
{ common_cpu: 0, cpu: 2 } hitcount: 1
{ common_cpu: 0, cpu: 4 } hitcount: 1
{ common_cpu: 7, cpu: 7 } hitcount: 1
{ common_cpu: 0, cpu: 7 } hitcount: 1
{ common_cpu: 0, cpu: 1 } hitcount: 1
{ common_cpu: 0, cpu: 6 } hitcount: 2
{ common_cpu: 0, cpu: 5 } hitcount: 2
{ common_cpu: 1, cpu: 1 } hitcount: 4
{ common_cpu: 6, cpu: 6 } hitcount: 4
{ common_cpu: 5, cpu: 5 } hitcount: 14
{ common_cpu: 4, cpu: 4 } hitcount: 26
{ common_cpu: 0, cpu: 0 } hitcount: 39
{ common_cpu: 2, cpu: 2 } hitcount: 184
Now for backward compatibility, I added a trick. If "cpu" is used, and
the field is not found, it will fall back to "common_cpu" and work as
it did before. This way, it will still work for old programs that use
"cpu" to get the actual CPU, but if the event has a "cpu" as a field, it
will get that event's "cpu" field, which is probably what it wants
anyway.
I updated the tracefs/README to include documentation about both the
common_timestamp and the common_cpu. This way, if that text is present in
the README, then an application can know that common_cpu is supported over
just plain "cpu".
Link: https://lkml.kernel.org/r/20210721110053.26b4f641@oasis.local.home
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Fixes:
|
||
|
Steven Rostedt (VMware)
|
3b13911a2f |
tracing: Synthetic event field_pos is an index not a boolean
Performing the following:
># echo 'wakeup_lat s32 pid; u64 delta; char wake_comm[]' > synthetic_events
># echo 'hist:keys=pid:__arg__1=common_timestamp.usecs' > events/sched/sched_waking/trigger
># echo 'hist:keys=next_pid:pid=next_pid,delta=common_timestamp.usecs-$__arg__1:onmatch(sched.sched_waking).trace(wakeup_lat,$pid,$delta,prev_comm)'\
> events/sched/sched_switch/trigger
># echo 1 > events/synthetic/enable
Crashed the kernel:
BUG: kernel NULL pointer dereference, address: 000000000000001b
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 7 PID: 0 Comm: swapper/7 Not tainted 5.13.0-rc5-test+ #104
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
RIP: 0010:strlen+0x0/0x20
Code: f6 82 80 2b 0b bc 20 74 11 0f b6 50 01 48 83 c0 01 f6 82 80 2b 0b bc
20 75 ef c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <80> 3f 00 74 10
48 89 f8 48 83 c0 01 80 38 9 f8 c3 31
RSP: 0018:ffffaa75000d79d0 EFLAGS: 00010046
RAX: 0000000000000002 RBX: ffff9cdb55575270 RCX: 0000000000000000
RDX: ffff9cdb58c7a320 RSI: ffffaa75000d7b40 RDI: 000000000000001b
RBP: ffffaa75000d7b40 R08: ffff9cdb40a4f010 R09: ffffaa75000d7ab8
R10: ffff9cdb4398c700 R11: 0000000000000008 R12: ffff9cdb58c7a320
R13: ffff9cdb55575270 R14: ffff9cdb58c7a000 R15: 0000000000000018
FS: 0000000000000000(0000) GS:ffff9cdb5aa00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000001b CR3: 00000000c0612006 CR4: 00000000001706e0
Call Trace:
trace_event_raw_event_synth+0x90/0x1d0
action_trace+0x5b/0x70
event_hist_trigger+0x4bd/0x4e0
? cpumask_next_and+0x20/0x30
? update_sd_lb_stats.constprop.0+0xf6/0x840
? __lock_acquire.constprop.0+0x125/0x550
? find_held_lock+0x32/0x90
? sched_clock_cpu+0xe/0xd0
? lock_release+0x155/0x440
? update_load_avg+0x8c/0x6f0
? enqueue_entity+0x18a/0x920
? __rb_reserve_next+0xe5/0x460
? ring_buffer_lock_reserve+0x12a/0x3f0
event_triggers_call+0x52/0xe0
trace_event_buffer_commit+0x1ae/0x240
trace_event_raw_event_sched_switch+0x114/0x170
__traceiter_sched_switch+0x39/0x50
__schedule+0x431/0xb00
schedule_idle+0x28/0x40
do_idle+0x198/0x2e0
cpu_startup_entry+0x19/0x20
secondary_startup_64_no_verify+0xc2/0xcb
The reason is that the dynamic events array keeps track of the field
position of the fields array, via the field_pos variable in the
synth_field structure. Unfortunately, that field is a boolean for some
reason, which means any field_pos greater than 1 will be a bug (in this
case it was 2).
Link: https://lkml.kernel.org/r/20210721191008.638bce34@oasis.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Fixes:
|
||
Linus Torvalds
|
4784dc99c7 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:
1) Fix type of bind option flag in af_xdp, from Baruch Siach.
2) Fix use after free in bpf_xdp_link_release(), from Xuan Zhao.
3) PM refcnt imbakance in r8152, from Takashi Iwai.
4) Sign extension ug in liquidio, from Colin Ian King.
5) Mising range check in s390 bpf jit, from Colin Ian King.
6) Uninit value in caif_seqpkt_sendmsg(), from Ziyong Xuan.
7) Fix skb page recycling race, from Ilias Apalodimas.
8) Fix memory leak in tcindex_partial_destroy_work, from Pave Skripkin.
9) netrom timer sk refcnt issues, from Nguyen Dinh Phi.
10) Fix data races aroun tcp's tfo_active_disable_stamp, from Eric
Dumazet.
11) act_skbmod should only operate on ethernet packets, from Peilin Ye.
12) Fix slab out-of-bpunds in fib6_nh_flush_exceptions(),, from Psolo
Abeni.
13) Fix sparx5 dependencies, from Yajun Deng.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (74 commits)
dpaa2-switch: seed the buffer pool after allocating the swp
net: sched: cls_api: Fix the the wrong parameter
net: sparx5: fix unmet dependencies warning
net: dsa: tag_ksz: dont let the hardware process the layer 4 checksum
net: dsa: ensure linearized SKBs in case of tail taggers
ravb: Remove extra TAB
ravb: Fix a typo in comment
net: dsa: sja1105: make VID 4095 a bridge VLAN too
tcp: disable TFO blackhole logic by default
sctp: do not update transport pathmtu if SPP_PMTUD_ENABLE is not set
net: ixp46x: fix ptp build failure
ibmvnic: Remove the proper scrq flush
selftests: net: add ESP-in-UDP PMTU test
udp: check encap socket in __udp_lib_err
sctp: update active_key for asoc when old key is being replaced
r8169: Avoid duplicate sysfs entry creation error
ixgbe: Fix packet corruption due to missing DMA sync
Revert "qed: fix possible unpaired spin_{un}lock_bh in _qed_mcp_cmd_and_union()"
ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions
fsl/fman: Add fibre support
...
|
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Haoran Luo
|
67f0d6d988 |
tracing: Fix bug in rb_per_cpu_empty() that might cause deadloop.
The "rb_per_cpu_empty()" misinterpret the condition (as not-empty) when "head_page" and "commit_page" of "struct ring_buffer_per_cpu" points to the same buffer page, whose "buffer_data_page" is empty and "read" field is non-zero. An error scenario could be constructed as followed (kernel perspective): 1. All pages in the buffer has been accessed by reader(s) so that all of them will have non-zero "read" field. 2. Read and clear all buffer pages so that "rb_num_of_entries()" will return 0 rendering there's no more data to read. It is also required that the "read_page", "commit_page" and "tail_page" points to the same page, while "head_page" is the next page of them. 3. Invoke "ring_buffer_lock_reserve()" with large enough "length" so that it shot pass the end of current tail buffer page. Now the "head_page", "commit_page" and "tail_page" points to the same page. 4. Discard current event with "ring_buffer_discard_commit()", so that "head_page", "commit_page" and "tail_page" points to a page whose buffer data page is now empty. When the error scenario has been constructed, "tracing_read_pipe" will be trapped inside a deadloop: "trace_empty()" returns 0 since "rb_per_cpu_empty()" returns 0 when it hits the CPU containing such constructed ring buffer. Then "trace_find_next_entry_inc()" always return NULL since "rb_num_of_entries()" reports there's no more entry to read. Finally "trace_seq_to_user()" returns "-EBUSY" spanking "tracing_read_pipe" back to the start of the "waitagain" loop. I've also written a proof-of-concept script to construct the scenario and trigger the bug automatically, you can use it to trace and validate my reasoning above: https://github.com/aegistudio/RingBufferDetonator.git Tests has been carried out on linux kernel 5.14-rc2 ( |
||
Yang Yingliang
|
b42b0bddcb |
workqueue: fix UAF in pwq_unbound_release_workfn()
I got a UAF report when doing fuzz test:
[ 152.880091][ T8030] ==================================================================
[ 152.881240][ T8030] BUG: KASAN: use-after-free in pwq_unbound_release_workfn+0x50/0x190
[ 152.882442][ T8030] Read of size 4 at addr ffff88810d31bd00 by task kworker/3:2/8030
[ 152.883578][ T8030]
[ 152.883932][ T8030] CPU: 3 PID: 8030 Comm: kworker/3:2 Not tainted 5.13.0+ #249
[ 152.885014][ T8030] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
[ 152.886442][ T8030] Workqueue: events pwq_unbound_release_workfn
[ 152.887358][ T8030] Call Trace:
[ 152.887837][ T8030] dump_stack_lvl+0x75/0x9b
[ 152.888525][ T8030] ? pwq_unbound_release_workfn+0x50/0x190
[ 152.889371][ T8030] print_address_description.constprop.10+0x48/0x70
[ 152.890326][ T8030] ? pwq_unbound_release_workfn+0x50/0x190
[ 152.891163][ T8030] ? pwq_unbound_release_workfn+0x50/0x190
[ 152.891999][ T8030] kasan_report.cold.15+0x82/0xdb
[ 152.892740][ T8030] ? pwq_unbound_release_workfn+0x50/0x190
[ 152.893594][ T8030] __asan_load4+0x69/0x90
[ 152.894243][ T8030] pwq_unbound_release_workfn+0x50/0x190
[ 152.895057][ T8030] process_one_work+0x47b/0x890
[ 152.895778][ T8030] worker_thread+0x5c/0x790
[ 152.896439][ T8030] ? process_one_work+0x890/0x890
[ 152.897163][ T8030] kthread+0x223/0x250
[ 152.897747][ T8030] ? set_kthread_struct+0xb0/0xb0
[ 152.898471][ T8030] ret_from_fork+0x1f/0x30
[ 152.899114][ T8030]
[ 152.899446][ T8030] Allocated by task 8884:
[ 152.900084][ T8030] kasan_save_stack+0x21/0x50
[ 152.900769][ T8030] __kasan_kmalloc+0x88/0xb0
[ 152.901416][ T8030] __kmalloc+0x29c/0x460
[ 152.902014][ T8030] alloc_workqueue+0x111/0x8e0
[ 152.902690][ T8030] __btrfs_alloc_workqueue+0x11e/0x2a0
[ 152.903459][ T8030] btrfs_alloc_workqueue+0x6d/0x1d0
[ 152.904198][ T8030] scrub_workers_get+0x1e8/0x490
[ 152.904929][ T8030] btrfs_scrub_dev+0x1b9/0x9c0
[ 152.905599][ T8030] btrfs_ioctl+0x122c/0x4e50
[ 152.906247][ T8030] __x64_sys_ioctl+0x137/0x190
[ 152.906916][ T8030] do_syscall_64+0x34/0xb0
[ 152.907535][ T8030] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 152.908365][ T8030]
[ 152.908688][ T8030] Freed by task 8884:
[ 152.909243][ T8030] kasan_save_stack+0x21/0x50
[ 152.909893][ T8030] kasan_set_track+0x20/0x30
[ 152.910541][ T8030] kasan_set_free_info+0x24/0x40
[ 152.911265][ T8030] __kasan_slab_free+0xf7/0x140
[ 152.911964][ T8030] kfree+0x9e/0x3d0
[ 152.912501][ T8030] alloc_workqueue+0x7d7/0x8e0
[ 152.913182][ T8030] __btrfs_alloc_workqueue+0x11e/0x2a0
[ 152.913949][ T8030] btrfs_alloc_workqueue+0x6d/0x1d0
[ 152.914703][ T8030] scrub_workers_get+0x1e8/0x490
[ 152.915402][ T8030] btrfs_scrub_dev+0x1b9/0x9c0
[ 152.916077][ T8030] btrfs_ioctl+0x122c/0x4e50
[ 152.916729][ T8030] __x64_sys_ioctl+0x137/0x190
[ 152.917414][ T8030] do_syscall_64+0x34/0xb0
[ 152.918034][ T8030] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 152.918872][ T8030]
[ 152.919203][ T8030] The buggy address belongs to the object at ffff88810d31bc00
[ 152.919203][ T8030] which belongs to the cache kmalloc-512 of size 512
[ 152.921155][ T8030] The buggy address is located 256 bytes inside of
[ 152.921155][ T8030] 512-byte region [ffff88810d31bc00, ffff88810d31be00)
[ 152.922993][ T8030] The buggy address belongs to the page:
[ 152.923800][ T8030] page:ffffea000434c600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10d318
[ 152.925249][ T8030] head:ffffea000434c600 order:2 compound_mapcount:0 compound_pincount:0
[ 152.926399][ T8030] flags: 0x57ff00000010200(slab|head|node=1|zone=2|lastcpupid=0x7ff)
[ 152.927515][ T8030] raw: 057ff00000010200 dead000000000100 dead000000000122 ffff888009c42c80
[ 152.928716][ T8030] raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
[ 152.929890][ T8030] page dumped because: kasan: bad access detected
[ 152.930759][ T8030]
[ 152.931076][ T8030] Memory state around the buggy address:
[ 152.931851][ T8030] ffff88810d31bc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 152.932967][ T8030] ffff88810d31bc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 152.934068][ T8030] >ffff88810d31bd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 152.935189][ T8030] ^
[ 152.935763][ T8030] ffff88810d31bd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 152.936847][ T8030] ffff88810d31be00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 152.937940][ T8030] ==================================================================
If apply_wqattrs_prepare() fails in alloc_workqueue(), it will call put_pwq()
which invoke a work queue to call pwq_unbound_release_workfn() and use the 'wq'.
The 'wq' allocated in alloc_workqueue() will be freed in error path when
apply_wqattrs_prepare() fails. So it will lead a UAF.
CPU0 CPU1
alloc_workqueue()
alloc_and_link_pwqs()
apply_wqattrs_prepare() fails
apply_wqattrs_cleanup()
schedule_work(&pwq->unbound_release_work)
kfree(wq)
worker_thread()
pwq_unbound_release_workfn() <- trigger uaf here
If apply_wqattrs_prepare() fails, the new pwq are not linked, it doesn't
hold any reference to the 'wq', 'wq' is invalid to access in the worker,
so add check pwq if linked to fix this.
Fixes:
|
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Paul Gortmaker
|
1e7107c5ef |
cgroup1: fix leaked context root causing sporadic NULL deref in LTP
Richard reported sporadic (roughly one in 10 or so) null dereferences and other strange behaviour for a set of automated LTP tests. Things like: BUG: kernel NULL pointer dereference, address: 0000000000000008 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 1516 Comm: umount Not tainted 5.10.0-yocto-standard #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-48-gd9c812dda519-prebuilt.qemu.org 04/01/2014 RIP: 0010:kernfs_sop_show_path+0x1b/0x60 ...or these others: RIP: 0010:do_mkdirat+0x6a/0xf0 RIP: 0010:d_alloc_parallel+0x98/0x510 RIP: 0010:do_readlinkat+0x86/0x120 There were other less common instances of some kind of a general scribble but the common theme was mount and cgroup and a dubious dentry triggering the NULL dereference. I was only able to reproduce it under qemu by replicating Richard's setup as closely as possible - I never did get it to happen on bare metal, even while keeping everything else the same. In commit |
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Thomas Gleixner
|
ff5a6a3550 |
Merge branch 'timers/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/urgent
Pull dyntick fixes from Frederic Weisbecker: - Fix a rearm race in the posix cpu timer code - Handle get_next_timer_interrupt() correctly when no timers are pending Link: https://lore.kernel.org/r/20210715104218.81276-1-frederic@kernel.org |
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Linus Torvalds
|
3fdacf402b |
Merge tag 'trace-v5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt: "Fix the histogram logic from possibly crashing the kernel Working on the histogram code, I found that if you dereference a char pointer in a trace event that happens to point to user space, it can crash the kernel, as it does no checks of that pointer. I have code coming that will do this better, so just remove this ability to treat character pointers in trace events as stings in the histogram" * tag 'trace-v5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Do not reference char * as a string in histograms |
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Linus Torvalds
|
6e442d0662 |
Merge branch 'urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu
Pull RCU fixes from Paul McKenney: - fix regressions induced by a merge-window change in scheduler semantics, which means that smp_processor_id() can no longer be used in kthreads using simple affinity to bind themselves to a specific CPU. - fix a bug in Tasks Trace RCU that was thought to be strictly theoretical. However, production workloads have started hitting this, so these fixes need to be merged sooner rather than later. - fix a minor printk()-format-mismatch issue introduced during the merge window. * 'urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: rcu: Fix pr_info() formats and values in show_rcu_gp_kthreads() rcu-tasks: Don't delete holdouts within trc_wait_for_one_reader() rcu-tasks: Don't delete holdouts within trc_inspect_reader() refscale: Avoid false-positive warnings in ref_scale_reader() scftorture: Avoid false-positive warnings in scftorture_invoker() |
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Marco Elver
|
b068fc04de |
perf: Refactor permissions check into perf_check_permission()
Refactor the permission check in perf_event_open() into a helper perf_check_permission(). This makes the permission check logic more readable (because we no longer have a negated disjunction). Add a comment mentioning the ptrace check also checks the uid. No functional change intended. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Link: https://lore.kernel.org/r/20210705084453.2151729-2-elver@google.com |
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Marco Elver
|
9d7a6c95f6 |
perf: Fix required permissions if sigtrap is requested
If perf_event_open() is called with another task as target and
perf_event_attr::sigtrap is set, and the target task's user does not
match the calling user, also require the CAP_KILL capability or
PTRACE_MODE_ATTACH permissions.
Otherwise, with the CAP_PERFMON capability alone it would be possible
for a user to send SIGTRAP signals via perf events to another user's
tasks. This could potentially result in those tasks being terminated if
they cannot handle SIGTRAP signals.
Note: The check complements the existing capability check, but is not
supposed to supersede the ptrace_may_access() check. At a high level we
now have:
capable of CAP_PERFMON and (CAP_KILL if sigtrap)
OR
ptrace_may_access(...) // also checks for same thread-group and uid
Fixes:
|
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Daniel Borkmann
|
e042aa532c |
bpf: Fix pointer arithmetic mask tightening under state pruning
In |
||
|
Daniel Borkmann
|
59089a189e |
bpf: Remove superfluous aux sanitation on subprog rejection
Follow-up to
|
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Roman Skakun
|
40ac971eab |
dma-mapping: handle vmalloc addresses in dma_common_{mmap,get_sgtable}
xen-swiotlb can use vmalloc backed addresses for dma coherent allocations
and uses the common helpers. Properly handle them to unbreak Xen on
ARM platforms.
Fixes:
|
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David S. Miller
|
20192d9c9f |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Andrii Nakryiko says: ==================== pull-request: bpf 2021-07-15 The following pull-request contains BPF updates for your *net* tree. We've added 9 non-merge commits during the last 5 day(s) which contain a total of 9 files changed, 37 insertions(+), 15 deletions(-). The main changes are: 1) Fix NULL pointer dereference in BPF_TEST_RUN for BPF_XDP_DEVMAP and BPF_XDP_CPUMAP programs, from Xuan Zhuo. 2) Fix use-after-free of net_device in XDP bpf_link, from Xuan Zhuo. 3) Follow-up fix to subprog poke descriptor use-after-free problem, from Daniel Borkmann and John Fastabend. 4) Fix out-of-range array access in s390 BPF JIT backend, from Colin Ian King. 5) Fix memory leak in BPF sockmap, from John Fastabend. 6) Fix for sockmap to prevent proc stats reporting bug, from John Fastabend and Jakub Sitnicki. 7) Fix NULL pointer dereference in bpftool, from Tobias Klauser. 8) AF_XDP documentation fixes, from Baruch Siach. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> |
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|
Steven Rostedt (VMware)
|
704adfb5a9 |
tracing: Do not reference char * as a string in histograms
The histogram logic was allowing events with char * pointers to be used as normal strings. But it was easy to crash the kernel with: # echo 'hist:keys=filename' > events/syscalls/sys_enter_openat/trigger And open some files, and boom! BUG: unable to handle page fault for address: 00007f2ced0c3280 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 1173fa067 P4D 1173fa067 PUD 1171b6067 PMD 1171dd067 PTE 0 Oops: 0000 [#1] PREEMPT SMP CPU: 6 PID: 1810 Comm: cat Not tainted 5.13.0-rc5-test+ #61 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:strlen+0x0/0x20 Code: f6 82 80 2a 0b a9 20 74 11 0f b6 50 01 48 83 c0 01 f6 82 80 2a 0b a9 20 75 ef c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <80> 3f 00 74 10 48 89 f8 48 83 c0 01 80 38 00 75 f7 48 29 f8 c3 RSP: 0018:ffffbdbf81567b50 EFLAGS: 00010246 RAX: 0000000000000003 RBX: ffff93815cdb3800 RCX: ffff9382401a22d0 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 00007f2ced0c3280 RBP: 0000000000000100 R08: ffff9382409ff074 R09: ffffbdbf81567c98 R10: ffff9382409ff074 R11: 0000000000000000 R12: ffff9382409ff074 R13: 0000000000000001 R14: ffff93815a744f00 R15: 00007f2ced0c3280 FS: 00007f2ced0f8580(0000) GS:ffff93825a800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2ced0c3280 CR3: 0000000107069005 CR4: 00000000001706e0 Call Trace: event_hist_trigger+0x463/0x5f0 ? find_held_lock+0x32/0x90 ? sched_clock_cpu+0xe/0xd0 ? lock_release+0x155/0x440 ? kernel_init_free_pages+0x6d/0x90 ? preempt_count_sub+0x9b/0xd0 ? kernel_init_free_pages+0x6d/0x90 ? get_page_from_freelist+0x12c4/0x1680 ? __rb_reserve_next+0xe5/0x460 ? ring_buffer_lock_reserve+0x12a/0x3f0 event_triggers_call+0x52/0xe0 ftrace_syscall_enter+0x264/0x2c0 syscall_trace_enter.constprop.0+0x1ee/0x210 do_syscall_64+0x1c/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Where it triggered a fault on strlen(key) where key was the filename. The reason is that filename is a char * to user space, and the histogram code just blindly dereferenced it, with obvious bad results. I originally tried to use strncpy_from_user/kernel_nofault() but found that there's other places that its dereferenced and not worth the effort. Just do not allow "char *" to act like strings. Link: https://lkml.kernel.org/r/20210715000206.025df9d2@rorschach.local.home Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: stable@vger.kernel.org Acked-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Tom Zanussi <zanussi@kernel.org> Fixes: |
||
|
Linus Torvalds
|
e9338abf0e |
Merge tag 'Wimplicit-fallthrough-clang-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux
Pull fallthrough fixes from Gustavo Silva: "This fixes many fall-through warnings when building with Clang and -Wimplicit-fallthrough, and also enables -Wimplicit-fallthrough for Clang, globally. It's also important to notice that since we have adopted the use of the pseudo-keyword macro fallthrough, we also want to avoid having more /* fall through */ comments being introduced. Contrary to GCC, Clang doesn't recognize any comments as implicit fall-through markings when the -Wimplicit-fallthrough option is enabled. So, in order to avoid having more comments being introduced, we use the option -Wimplicit-fallthrough=5 for GCC, which similar to Clang, will cause a warning in case a code comment is intended to be used as a fall-through marking. The patch for Makefile also enforces this. We had almost 4,000 of these issues for Clang in the beginning, and there might be a couple more out there when building some architectures with certain configurations. However, with the recent fixes I think we are in good shape and it is now possible to enable the warning for Clang" * tag 'Wimplicit-fallthrough-clang-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (27 commits) Makefile: Enable -Wimplicit-fallthrough for Clang powerpc/smp: Fix fall-through warning for Clang dmaengine: mpc512x: Fix fall-through warning for Clang usb: gadget: fsl_qe_udc: Fix fall-through warning for Clang powerpc/powernv: Fix fall-through warning for Clang MIPS: Fix unreachable code issue MIPS: Fix fall-through warnings for Clang ASoC: Mediatek: MT8183: Fix fall-through warning for Clang power: supply: Fix fall-through warnings for Clang dmaengine: ti: k3-udma: Fix fall-through warning for Clang s390: Fix fall-through warnings for Clang dmaengine: ipu: Fix fall-through warning for Clang iommu/arm-smmu-v3: Fix fall-through warning for Clang mmc: jz4740: Fix fall-through warning for Clang PCI: Fix fall-through warning for Clang scsi: libsas: Fix fall-through warning for Clang video: fbdev: Fix fall-through warning for Clang math-emu: Fix fall-through warning cpufreq: Fix fall-through warning for Clang drm/msm: Fix fall-through warning in msm_gem_new_impl() ... |
||
Nicolas Saenz Julienne
|
aebacb7f6c |
timers: Fix get_next_timer_interrupt() with no timers pending
|
||
Frederic Weisbecker
|
1a3402d93c |
posix-cpu-timers: Fix rearm racing against process tick
Since the process wide cputime counter is started locklessly from
posix_cpu_timer_rearm(), it can be concurrently stopped by operations
on other timers from the same thread group, such as in the following
unlucky scenario:
CPU 0 CPU 1
----- -----
timer_settime(TIMER B)
posix_cpu_timer_rearm(TIMER A)
cpu_clock_sample_group()
(pct->timers_active already true)
handle_posix_cpu_timers()
check_process_timers()
stop_process_timers()
pct->timers_active = false
arm_timer(TIMER A)
tick -> run_posix_cpu_timers()
// sees !pct->timers_active, ignore
// our TIMER A
Fix this with simply locking process wide cputime counting start and
timer arm in the same block.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Fixes:
|
||
|
Linus Torvalds
|
8096acd744 |
Merge tag 'net-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski.
"Including fixes from bpf and netfilter.
Current release - regressions:
- sock: fix parameter order in sock_setsockopt()
Current release - new code bugs:
- netfilter: nft_last:
- fix incorrect arithmetic when restoring last used
- honor NFTA_LAST_SET on restoration
Previous releases - regressions:
- udp: properly flush normal packet at GRO time
- sfc: ensure correct number of XDP queues; don't allow enabling the
feature if there isn't sufficient resources to Tx from any CPU
- dsa: sja1105: fix address learning getting disabled on the CPU port
- mptcp: addresses a rmem accounting issue that could keep packets in
subflow receive buffers longer than necessary, delaying MPTCP-level
ACKs
- ip_tunnel: fix mtu calculation for ETHER tunnel devices
- do not reuse skbs allocated from skbuff_fclone_cache in the napi
skb cache, we'd try to return them to the wrong slab cache
- tcp: consistently disable header prediction for mptcp
Previous releases - always broken:
- bpf: fix subprog poke descriptor tracking use-after-free
- ipv6:
- allocate enough headroom in ip6_finish_output2() in case
iptables TEE is used
- tcp: drop silly ICMPv6 packet too big messages to avoid
expensive and pointless lookups (which may serve as a DDOS
vector)
- make sure fwmark is copied in SYNACK packets
- fix 'disable_policy' for forwarded packets (align with IPv4)
- netfilter: conntrack:
- do not renew entry stuck in tcp SYN_SENT state
- do not mark RST in the reply direction coming after SYN packet
for an out-of-sync entry
- mptcp: cleanly handle error conditions with MP_JOIN and syncookies
- mptcp: fix double free when rejecting a join due to port mismatch
- validate lwtstate->data before returning from skb_tunnel_info()
- tcp: call sk_wmem_schedule before sk_mem_charge in zerocopy path
- mt76: mt7921: continue to probe driver when fw already downloaded
- bonding: fix multiple issues with offloading IPsec to (thru?) bond
- stmmac: ptp: fix issues around Qbv support and setting time back
- bcmgenet: always clear wake-up based on energy detection
Misc:
- sctp: move 198 addresses from unusable to private scope
- ptp: support virtual clocks and timestamping
- openvswitch: optimize operation for key comparison"
* tag 'net-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (158 commits)
net: dsa: properly check for the bridge_leave methods in dsa_switch_bridge_leave()
sfc: add logs explaining XDP_TX/REDIRECT is not available
sfc: ensure correct number of XDP queues
sfc: fix lack of XDP TX queues - error XDP TX failed (-22)
net: fddi: fix UAF in fza_probe
net: dsa: sja1105: fix address learning getting disabled on the CPU port
net: ocelot: fix switchdev objects synced for wrong netdev with LAG offload
net: Use nlmsg_unicast() instead of netlink_unicast()
octeontx2-pf: Fix uninitialized boolean variable pps
ipv6: allocate enough headroom in ip6_finish_output2()
net: hdlc: rename 'mod_init' & 'mod_exit' functions to be module-specific
net: bridge: multicast: fix MRD advertisement router port marking race
net: bridge: multicast: fix PIM hello router port marking race
net: phy: marvell10g: fix differentiation of 88X3310 from 88X3340
dsa: fix for_each_child.cocci warnings
virtio_net: check virtqueue_add_sgs() return value
mptcp: properly account bulk freed memory
selftests: mptcp: fix case multiple subflows limited by server
mptcp: avoid processing packet if a subflow reset
mptcp: fix syncookie process if mptcp can not_accept new subflow
...
|
||
Christian Brauner
|
d1d488d813 |
fs: add vfs_parse_fs_param_source() helper
Add a simple helper that filesystems can use in their parameter parser to parse the "source" parameter. A few places open-coded this function and that already caused a bug in the cgroup v1 parser that we fixed. Let's make it harder to get this wrong by introducing a helper which performs all necessary checks. Link: https://syzkaller.appspot.com/bug?id=6312526aba5beae046fdae8f00399f87aab48b12 Cc: Christoph Hellwig <hch@lst.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Christian Brauner
|
3b0462726e |
cgroup: verify that source is a string
The following sequence can be used to trigger a UAF:
int fscontext_fd = fsopen("cgroup");
int fd_null = open("/dev/null, O_RDONLY);
int fsconfig(fscontext_fd, FSCONFIG_SET_FD, "source", fd_null);
close_range(3, ~0U, 0);
The cgroup v1 specific fs parser expects a string for the "source"
parameter. However, it is perfectly legitimate to e.g. specify a file
descriptor for the "source" parameter. The fs parser doesn't know what
a filesystem allows there. So it's a bug to assume that "source" is
always of type fs_value_is_string when it can reasonably also be
fs_value_is_file.
This assumption in the cgroup code causes a UAF because struct
fs_parameter uses a union for the actual value. Access to that union is
guarded by the param->type member. Since the cgroup paramter parser
didn't check param->type but unconditionally moved param->string into
fc->source a close on the fscontext_fd would trigger a UAF during
put_fs_context() which frees fc->source thereby freeing the file stashed
in param->file causing a UAF during a close of the fd_null.
Fix this by verifying that param->type is actually a string and report
an error if not.
In follow up patches I'll add a new generic helper that can be used here
and by other filesystems instead of this error-prone copy-pasta fix.
But fixing it in here first makes backporting a it to stable a lot
easier.
Fixes:
|
||
|
Daniel Borkmann
|
5dd0a6b858 |
bpf: Fix tail_call_reachable rejection for interpreter when jit failed
During testing of |
||
Ingo Molnar
|
e9ba16e68c |
smpboot: Mark idle_init() as __always_inlined to work around aggressive compiler un-inlining
While this function is a static inline, and is only used once in local scope, certain Kconfig variations may cause it to be compiled as a standalone function: 89231bf0 <idle_init>: 89231bf0: 83 05 60 d9 45 89 01 addl $0x1,0x8945d960 89231bf7: 55 push %ebp Resulting in this build failure: WARNING: modpost: vmlinux.o(.text.unlikely+0x7fd5): Section mismatch in reference from the function idle_init() to the function .init.text:fork_idle() The function idle_init() references the function __init fork_idle(). This is often because idle_init lacks a __init annotation or the annotation of fork_idle is wrong. ERROR: modpost: Section mismatches detected. Certain USBSAN options x86-32 builds with CONFIG_CC_OPTIMIZE_FOR_SIZE=y seem to be causing this. So mark idle_init() as __always_inline to work around this compiler bug/feature. Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
Gustavo A. R. Silva
|
1adee589cd |
kernel: debug: Fix unreachable code in gdb_serial_stub()
Fix the following warning:
kernel/debug/gdbstub.c:1049:4: warning: fallthrough annotation in unreachable code [-Wimplicit-fallthrough]
fallthrough;
^
include/linux/compiler_attributes.h:210:41: note: expanded from macro 'fallthrough'
# define fallthrough __attribute__((__fallthrough__)
by placing the fallthrough; statement inside ifdeffery.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
|
||
|
Linus Torvalds
|
98f7fdced2 |
Merge tag 'irq-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Ingo Molnar:
"Two fixes:
- Fix a MIPS IRQ handling RCU bug
- Remove a DocBook annotation for a parameter that doesn't exist
anymore"
* tag 'irq-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/mips: Fix RCU violation when using irqdomain lookup on interrupt entry
genirq/irqdesc: Drop excess kernel-doc entry @lookup
|
||
|
Linus Torvalds
|
877029d921 |
Merge tag 'sched-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar: "Three fixes: - Fix load tracking bug/inconsistency - Fix a sporadic CFS bandwidth constraints enforcement bug - Fix a uclamp utilization tracking bug for newly woken tasks" * tag 'sched-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/uclamp: Ignore max aggregation if rq is idle sched/fair: Fix CFS bandwidth hrtimer expiry type sched/fair: Sync load_sum with load_avg after dequeue |
||
|
Linus Torvalds
|
301c8b1d7c |
Merge tag 'locking-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar: - Fix a Sparc crash - Fix a number of objtool warnings - Fix /proc/lockdep output on certain configs - Restore a kprobes fail-safe * tag 'locking-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/atomic: sparc: Fix arch_cmpxchg64_local() kprobe/static_call: Restore missing static_call_text_reserved() static_call: Fix static_call_text_reserved() vs __init jump_label: Fix jump_label_text_reserved() vs __init locking/lockdep: Fix meaningless /proc/lockdep output of lock classes on !CONFIG_PROVE_LOCKING |
||
|
Linus Torvalds
|
81361b837a |
Merge tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Increase the -falign-functions alignment for the debug option.
- Remove ugly libelf checks from the top Makefile.
- Make the silent build (-s) more silent.
- Re-compile the kernel if KBUILD_BUILD_TIMESTAMP is specified.
- Various script cleanups
* tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (27 commits)
scripts: add generic syscallnr.sh
scripts: check duplicated syscall number in syscall table
sparc: syscalls: use pattern rules to generate syscall headers
parisc: syscalls: use pattern rules to generate syscall headers
nds32: add arch/nds32/boot/.gitignore
kbuild: mkcompile_h: consider timestamp if KBUILD_BUILD_TIMESTAMP is set
kbuild: modpost: Explicitly warn about unprototyped symbols
kbuild: remove trailing slashes from $(KBUILD_EXTMOD)
kconfig.h: explain IS_MODULE(), IS_ENABLED()
kconfig: constify long_opts
scripts/setlocalversion: simplify the short version part
scripts/setlocalversion: factor out 12-chars hash construction
scripts/setlocalversion: add more comments to -dirty flag detection
scripts/setlocalversion: remove workaround for old make-kpkg
scripts/setlocalversion: remove mercurial, svn and git-svn supports
kbuild: clean up ${quiet} checks in shell scripts
kbuild: sink stdout from cmd for silent build
init: use $(call cmd,) for generating include/generated/compile.h
kbuild: merge scripts/mkmakefile to top Makefile
sh: move core-y in arch/sh/Makefile to arch/sh/Kbuild
...
|
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|
Linus Torvalds
|
5a7f7fc5dd |
Merge tag 'trace-v5.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix and cleanup from Steven Rostedt:
"Tracing fix for histograms and a clean up in ftrace:
- Fixed a bug that broke the .sym-offset modifier and added a test to
make sure nothing breaks it again.
- Replace a list_del/list_add() with a list_move()"
* tag 'trace-v5.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Use list_move instead of list_del/list_add
tracing/selftests: Add tests to test histogram sym and sym-offset modifiers
tracing/histograms: Fix parsing of "sym-offset" modifier
|
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|
Linus Torvalds
|
bd9c350603 |
Merge branch 'akpm' (patches from Andrew)
Pull yet more updates from Andrew Morton: "54 patches. Subsystems affected by this patch series: lib, mm (slub, secretmem, cleanups, init, pagemap, and mremap), and debug" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (54 commits) powerpc/mm: enable HAVE_MOVE_PMD support powerpc/book3s64/mm: update flush_tlb_range to flush page walk cache mm/mremap: allow arch runtime override mm/mremap: hold the rmap lock in write mode when moving page table entries. mm/mremap: use pmd/pud_poplulate to update page table entries mm/mremap: don't enable optimized PUD move if page table levels is 2 mm/mremap: convert huge PUD move to separate helper selftest/mremap_test: avoid crash with static build selftest/mremap_test: update the test to handle pagesize other than 4K mm: rename p4d_page_vaddr to p4d_pgtable and make it return pud_t * mm: rename pud_page_vaddr to pud_pgtable and make it return pmd_t * kdump: use vmlinux_build_id to simplify buildid: fix kernel-doc notation buildid: mark some arguments const scripts/decode_stacktrace.sh: indicate 'auto' can be used for base path scripts/decode_stacktrace.sh: silence stderr messages from addr2line/nm scripts/decode_stacktrace.sh: support debuginfod x86/dumpstack: use %pSb/%pBb for backtrace printing arm64: stacktrace: use %pSb for backtrace printing module: add printk formats to add module build ID to stacktraces ... |
||
|
Thomas Gleixner
|
4840048356 |
Merge tag 'irqchip-fixes-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent
Pull irqchip fixes from Marc Zyngier: - Fix a MIPS bug where irqdomain loopkups could occur in a context where RCU is not allowed - Fix a documentation bug for handle_domain_irq |
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John Fastabend
|
f263a81451 |
bpf: Track subprog poke descriptors correctly and fix use-after-free
Subprograms are calling map_poke_track(), but on program release there is no hook to call map_poke_untrack(). However, on program release, the aux memory (and poke descriptor table) is freed even though we still have a reference to it in the element list of the map aux data. When we run map_poke_run(), we then end up accessing free'd memory, triggering KASAN in prog_array_map_poke_run(): [...] [ 402.824689] BUG: KASAN: use-after-free in prog_array_map_poke_run+0xc2/0x34e [ 402.824698] Read of size 4 at addr ffff8881905a7940 by task hubble-fgs/4337 [ 402.824705] CPU: 1 PID: 4337 Comm: hubble-fgs Tainted: G I 5.12.0+ #399 [ 402.824715] Call Trace: [ 402.824719] dump_stack+0x93/0xc2 [ 402.824727] print_address_description.constprop.0+0x1a/0x140 [ 402.824736] ? prog_array_map_poke_run+0xc2/0x34e [ 402.824740] ? prog_array_map_poke_run+0xc2/0x34e [ 402.824744] kasan_report.cold+0x7c/0xd8 [ 402.824752] ? prog_array_map_poke_run+0xc2/0x34e [ 402.824757] prog_array_map_poke_run+0xc2/0x34e [ 402.824765] bpf_fd_array_map_update_elem+0x124/0x1a0 [...] The elements concerned are walked as follows: for (i = 0; i < elem->aux->size_poke_tab; i++) { poke = &elem->aux->poke_tab[i]; [...] The access to size_poke_tab is a 4 byte read, verified by checking offsets in the KASAN dump: [ 402.825004] The buggy address belongs to the object at ffff8881905a7800 which belongs to the cache kmalloc-1k of size 1024 [ 402.825008] The buggy address is located 320 bytes inside of 1024-byte region [ffff8881905a7800, ffff8881905a7c00) The pahole output of bpf_prog_aux: struct bpf_prog_aux { [...] /* --- cacheline 5 boundary (320 bytes) --- */ u32 size_poke_tab; /* 320 4 */ [...] In general, subprograms do not necessarily manage their own data structures. For example, BTF func_info and linfo are just pointers to the main program structure. This allows reference counting and cleanup to be done on the latter which simplifies their management a bit. The aux->poke_tab struct, however, did not follow this logic. The initial proposed fix for this use-after-free bug further embedded poke data tracking into the subprogram with proper reference counting. However, Daniel and Alexei questioned why we were treating these objects special; I agree, its unnecessary. The fix here removes the per subprogram poke table allocation and map tracking and instead simply points the aux->poke_tab pointer at the main programs poke table. This way, map tracking is simplified to the main program and we do not need to manage them per subprogram. This also means, bpf_prog_free_deferred(), which unwinds the program reference counting and kfrees objects, needs to ensure that we don't try to double free the poke_tab when free'ing the subprog structures. This is easily solved by NULL'ing the poke_tab pointer. The second detail is to ensure that per subprogram JIT logic only does fixups on poke_tab[] entries it owns. To do this, we add a pointer in the poke structure to point at the subprogram value so JITs can easily check while walking the poke_tab structure if the current entry belongs to the current program. The aux pointer is stable and therefore suitable for such comparison. On the jit_subprogs() error path, we omit cleaning up the poke->aux field because these are only ever referenced from the JIT side, but on error we will never make it to the JIT, so its fine to leave them dangling. Removing these pointers would complicate the error path for no reason. However, we do need to untrack all poke descriptors from the main program as otherwise they could race with the freeing of JIT memory from the subprograms. Lastly, |
||
Stephen Boyd
|
44e8a5e912 |
kdump: use vmlinux_build_id to simplify
We can use the vmlinux_build_id array here now instead of open coding it. This mostly consolidates code. Link: https://lkml.kernel.org/r/20210511003845.2429846-14-swboyd@chromium.org Signed-off-by: Stephen Boyd <swboyd@chromium.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Evan Green <evgreen@chromium.org> Cc: Hsin-Yi Wang <hsinyi@chromium.org> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Matthew Wilcox <willy@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Sasha Levin <sashal@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Stephen Boyd
|
9294523e37 |
module: add printk formats to add module build ID to stacktraces
Let's make kernel stacktraces easier to identify by including the build ID[1] of a module if the stacktrace is printing a symbol from a module. This makes it simpler for developers to locate a kernel module's full debuginfo for a particular stacktrace. Combined with scripts/decode_stracktrace.sh, a developer can download the matching debuginfo from a debuginfod[2] server and find the exact file and line number for the functions plus offsets in a stacktrace that match the module. This is especially useful for pstore crash debugging where the kernel crashes are recorded in something like console-ramoops and the recovery kernel/modules are different or the debuginfo doesn't exist on the device due to space concerns (the debuginfo can be too large for space limited devices). Originally, I put this on the %pS format, but that was quickly rejected given that %pS is used in other places such as ftrace where build IDs aren't meaningful. There was some discussions on the list to put every module build ID into the "Modules linked in:" section of the stacktrace message but that quickly becomes very hard to read once you have more than three or four modules linked in. It also provides too much information when we don't expect each module to be traversed in a stacktrace. Having the build ID for modules that aren't important just makes things messy. Splitting it to multiple lines for each module quickly explodes the number of lines printed in an oops too, possibly wrapping the warning off the console. And finally, trying to stash away each module used in a callstack to provide the ID of each symbol printed is cumbersome and would require changes to each architecture to stash away modules and return their build IDs once unwinding has completed. Instead, we opt for the simpler approach of introducing new printk formats '%pS[R]b' for "pointer symbolic backtrace with module build ID" and '%pBb' for "pointer backtrace with module build ID" and then updating the few places in the architecture layer where the stacktrace is printed to use this new format. Before: Call trace: lkdtm_WARNING+0x28/0x30 [lkdtm] direct_entry+0x16c/0x1b4 [lkdtm] full_proxy_write+0x74/0xa4 vfs_write+0xec/0x2e8 After: Call trace: lkdtm_WARNING+0x28/0x30 [lkdtm 6c2215028606bda50de823490723dc4bc5bf46f9] direct_entry+0x16c/0x1b4 [lkdtm 6c2215028606bda50de823490723dc4bc5bf46f9] full_proxy_write+0x74/0xa4 vfs_write+0xec/0x2e8 [akpm@linux-foundation.org: fix build with CONFIG_MODULES=n, tweak code layout] [rdunlap@infradead.org: fix build when CONFIG_MODULES is not set] Link: https://lkml.kernel.org/r/20210513171510.20328-1-rdunlap@infradead.org [akpm@linux-foundation.org: make kallsyms_lookup_buildid() static] [cuibixuan@huawei.com: fix build error when CONFIG_SYSFS is disabled] Link: https://lkml.kernel.org/r/20210525105049.34804-1-cuibixuan@huawei.com Link: https://lkml.kernel.org/r/20210511003845.2429846-6-swboyd@chromium.org Link: https://fedoraproject.org/wiki/Releases/FeatureBuildId [1] Link: https://sourceware.org/elfutils/Debuginfod.html [2] Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Bixuan Cui <cuibixuan@huawei.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Evan Green <evgreen@chromium.org> Cc: Hsin-Yi Wang <hsinyi@chromium.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Matthew Wilcox <willy@infradead.org> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Sasha Levin <sashal@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Mike Rapoport
|
9a436f8ff6 |
PM: hibernate: disable when there are active secretmem users
It is unsafe to allow saving of secretmem areas to the hibernation snapshot as they would be visible after the resume and this essentially will defeat the purpose of secret memory mappings. Prevent hibernation whenever there are active secret memory users. Link: https://lkml.kernel.org/r/20210518072034.31572-6-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christopher Lameter <cl@linux.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Elena Reshetova <elena.reshetova@intel.com> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Bottomley <jejb@linux.ibm.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Palmer Dabbelt <palmerdabbelt@google.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tycho Andersen <tycho@tycho.ws> Cc: Will Deacon <will@kernel.org> Cc: kernel test robot <lkp@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Mike Rapoport
|
1507f51255 |
mm: introduce memfd_secret system call to create "secret" memory areas
Introduce "memfd_secret" system call with the ability to create memory
areas visible only in the context of the owning process and not mapped not
only to other processes but in the kernel page tables as well.
The secretmem feature is off by default and the user must explicitly
enable it at the boot time.
Once secretmem is enabled, the user will be able to create a file
descriptor using the memfd_secret() system call. The memory areas created
by mmap() calls from this file descriptor will be unmapped from the kernel
direct map and they will be only mapped in the page table of the processes
that have access to the file descriptor.
Secretmem is designed to provide the following protections:
* Enhanced protection (in conjunction with all the other in-kernel
attack prevention systems) against ROP attacks. Seceretmem makes
"simple" ROP insufficient to perform exfiltration, which increases the
required complexity of the attack. Along with other protections like
the kernel stack size limit and address space layout randomization which
make finding gadgets is really hard, absence of any in-kernel primitive
for accessing secret memory means the one gadget ROP attack can't work.
Since the only way to access secret memory is to reconstruct the missing
mapping entry, the attacker has to recover the physical page and insert
a PTE pointing to it in the kernel and then retrieve the contents. That
takes at least three gadgets which is a level of difficulty beyond most
standard attacks.
* Prevent cross-process secret userspace memory exposures. Once the
secret memory is allocated, the user can't accidentally pass it into the
kernel to be transmitted somewhere. The secreremem pages cannot be
accessed via the direct map and they are disallowed in GUP.
* Harden against exploited kernel flaws. In order to access secretmem,
a kernel-side attack would need to either walk the page tables and
create new ones, or spawn a new privileged uiserspace process to perform
secrets exfiltration using ptrace.
The file descriptor based memory has several advantages over the
"traditional" mm interfaces, such as mlock(), mprotect(), madvise(). File
descriptor approach allows explicit and controlled sharing of the memory
areas, it allows to seal the operations. Besides, file descriptor based
memory paves the way for VMMs to remove the secret memory range from the
userspace hipervisor process, for instance QEMU. Andy Lutomirski says:
"Getting fd-backed memory into a guest will take some possibly major
work in the kernel, but getting vma-backed memory into a guest without
mapping it in the host user address space seems much, much worse."
memfd_secret() is made a dedicated system call rather than an extension to
memfd_create() because it's purpose is to allow the user to create more
secure memory mappings rather than to simply allow file based access to
the memory. Nowadays a new system call cost is negligible while it is way
simpler for userspace to deal with a clear-cut system calls than with a
multiplexer or an overloaded syscall. Moreover, the initial
implementation of memfd_secret() is completely distinct from
memfd_create() so there is no much sense in overloading memfd_create() to
begin with. If there will be a need for code sharing between these
implementation it can be easily achieved without a need to adjust user
visible APIs.
The secret memory remains accessible in the process context using uaccess
primitives, but it is not exposed to the kernel otherwise; secret memory
areas are removed from the direct map and functions in the
follow_page()/get_user_page() family will refuse to return a page that
belongs to the secret memory area.
Once there will be a use case that will require exposing secretmem to the
kernel it will be an opt-in request in the system call flags so that user
would have to decide what data can be exposed to the kernel.
Removing of the pages from the direct map may cause its fragmentation on
architectures that use large pages to map the physical memory which
affects the system performance. However, the original Kconfig text for
CONFIG_DIRECT_GBPAGES said that gigabyte pages in the direct map "... can
improve the kernel's performance a tiny bit ..." (commit
|
||
Alexey Gladkov
|
f3791f4df5 |
Fix UCOUNT_RLIMIT_SIGPENDING counter leak
We must properly handle an errors when we increase the rlimit counter
and the ucounts reference counter. We have to this with RCU protection
to prevent possible use-after-free that could occur due to concurrent
put_cred_rcu().
The following reproducer triggers the problem:
$ cat testcase.sh
case "${STEP:-0}" in
0)
ulimit -Si 1
ulimit -Hi 1
STEP=1 unshare -rU "$0"
killall sleep
;;
1)
for i in 1 2 3 4 5; do unshare -rU sleep 5 & done
;;
esac
with the KASAN report being along the lines of
BUG: KASAN: use-after-free in put_ucounts+0x17/0xa0
Write of size 4 at addr ffff8880045f031c by task swapper/2/0
CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.13.0+ #19
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-alt4 04/01/2014
Call Trace:
<IRQ>
put_ucounts+0x17/0xa0
put_cred_rcu+0xd5/0x190
rcu_core+0x3bf/0xcb0
__do_softirq+0xe3/0x341
irq_exit_rcu+0xbe/0xe0
sysvec_apic_timer_interrupt+0x6a/0x90
</IRQ>
asm_sysvec_apic_timer_interrupt+0x12/0x20
default_idle_call+0x53/0x130
do_idle+0x311/0x3c0
cpu_startup_entry+0x14/0x20
secondary_startup_64_no_verify+0xc2/0xcb
Allocated by task 127:
kasan_save_stack+0x1b/0x40
__kasan_kmalloc+0x7c/0x90
alloc_ucounts+0x169/0x2b0
set_cred_ucounts+0xbb/0x170
ksys_unshare+0x24c/0x4e0
__x64_sys_unshare+0x16/0x20
do_syscall_64+0x37/0x70
entry_SYSCALL_64_after_hwframe+0x44/0xae
Freed by task 0:
kasan_save_stack+0x1b/0x40
kasan_set_track+0x1c/0x30
kasan_set_free_info+0x20/0x30
__kasan_slab_free+0xeb/0x120
kfree+0xaa/0x460
put_cred_rcu+0xd5/0x190
rcu_core+0x3bf/0xcb0
__do_softirq+0xe3/0x341
The buggy address belongs to the object at ffff8880045f0300
which belongs to the cache kmalloc-192 of size 192
The buggy address is located 28 bytes inside of
192-byte region [ffff8880045f0300, ffff8880045f03c0)
The buggy address belongs to the page:
page:000000008de0a388 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880045f0000 pfn:0x45f0
flags: 0x100000000000200(slab|node=0|zone=1)
raw: 0100000000000200 ffffea00000f4640 0000000a0000000a ffff888001042a00
raw: ffff8880045f0000 000000008010000d 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8880045f0200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880045f0280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff8880045f0300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880045f0380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff8880045f0400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Disabling lock debugging due to kernel taint
Fixes:
|
||
Baokun Li
|
3ecda64475 |
ftrace: Use list_move instead of list_del/list_add
Using list_move() instead of list_del() + list_add(). Link: https://lkml.kernel.org/r/20210608031108.2820996-1-libaokun1@huawei.com Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> |
||
|
Linus Torvalds
|
aef4226f91 |
Merge tag 'pm-5.14-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki:
"These include cpufreq core simplifications and fixes, cpufreq driver
updates, cpuidle driver update, a generic power domains (genpd)
locking fix and a debug-related simplification of the PM core.
Specifics:
- Drop the ->stop_cpu() (not really useful) and ->resolve_freq()
(unused) cpufreq driver callbacks and modify the users of the
former accordingly (Viresh Kumar, Rafael Wysocki).
- Add frequency invariance support to the ACPI CPPC cpufreq driver
again along with the related fixes and cleanups (Viresh Kumar).
- Update the Meditak, qcom and SCMI ARM cpufreq drivers (Fabien
Parent, Seiya Wang, Sibi Sankar, Christophe JAILLET).
- Rename black/white-lists in the DT cpufreq driver (Viresh Kumar).
- Add generic performance domains support to the dvfs DT bindings
(Sudeep Holla).
- Refine locking in the generic power domains (genpd) support code to
avoid lock dependency issues (Stephen Boyd).
- Update the MSM and qcom ARM cpuidle drivers (Bartosz Dudziak).
- Simplify the PM core debug code by using ktime_us_delta() to
compute time interval lengths (Mark-PK Tsai)"
* tag 'pm-5.14-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (21 commits)
PM: domains: Shrink locking area of the gpd_list_lock
PM: sleep: Use ktime_us_delta() in initcall_debug_report()
cpufreq: CPPC: Add support for frequency invariance
arch_topology: Avoid use-after-free for scale_freq_data
cpufreq: CPPC: Pass structure instance by reference
cpufreq: CPPC: Fix potential memleak in cppc_cpufreq_cpu_init
cpufreq: Remove ->resolve_freq()
cpufreq: Reuse cpufreq_driver_resolve_freq() in __cpufreq_driver_target()
cpufreq: Remove the ->stop_cpu() driver callback
cpufreq: powernv: Migrate to ->exit() callback instead of ->stop_cpu()
cpufreq: CPPC: Migrate to ->exit() callback instead of ->stop_cpu()
cpufreq: intel_pstate: Combine ->stop_cpu() and ->offline()
cpuidle: qcom: Add SPM register data for MSM8226
dt-bindings: arm: msm: Add SAW2 for MSM8226
dt-bindings: cpufreq: update cpu type and clock name for MT8173 SoC
clk: mediatek: remove deprecated CLK_INFRA_CA57SEL for MT8173 SoC
cpufreq: dt: Rename black/white-lists
cpufreq: scmi: Fix an error message
cpufreq: mediatek: add support for mt8365
dt-bindings: dvfs: Add support for generic performance domains
...
|
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|
Linus Torvalds
|
a931dd33d3 |
Merge tag 'modules-for-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu: - Fix incorrect logic in module_kallsyms_on_each_symbol() - Fix for a Coccinelle warning * tag 'modules-for-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: correctly exit module_kallsyms_on_each_symbol when fn() != 0 kernel/module: Use BUG_ON instead of if condition followed by BUG |
||
|
Steven Rostedt (VMware)
|
26c5637310 |
tracing/histograms: Fix parsing of "sym-offset" modifier
With the addition of simple mathematical operations (plus and minus), the
parsing of the "sym-offset" modifier broke, as it took the '-' part of the
"sym-offset" as a minus, and tried to break it up into a mathematical
operation of "field.sym - offset", in which case it failed to parse
(unless the event had a field called "offset").
Both .sym and .sym-offset modifiers should not be entered into
mathematical calculations anyway. If ".sym-offset" is found in the
modifier, then simply make it not an operation that can be calculated on.
Link: https://lkml.kernel.org/r/20210707110821.188ae255@oasis.local.home
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: stable@vger.kernel.org
Fixes:
|
||
Paul E. McKenney
|
2a2ed5618a |
rcu: Fix pr_info() formats and values in show_rcu_gp_kthreads()
This commit changes from "%lx" to "%x" and from "0x1ffffL" to "0x1ffff" to match the change in type between the old field ->state (unsigned long) and the new field ->__state (unsigned int). Signed-off-by: Paul E. McKenney <paulmck@kernel.org> |
||
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Paul E. McKenney
|
a9ab9cce93 |
rcu-tasks: Don't delete holdouts within trc_wait_for_one_reader()
Invoking trc_del_holdout() from within trc_wait_for_one_reader() is only a performance optimization because the RCU Tasks Trace grace-period kthread will eventually do this within check_all_holdout_tasks_trace(). But it is not a particularly important performance optimization because it only applies to the grace-period kthread, of which there is but one. This commit therefore removes this invocation of trc_del_holdout() in favor of the one in check_all_holdout_tasks_trace() in the grace-period kthread. Reported-by: "Xu, Yanfei" <yanfei.xu@windriver.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> |
||
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Paul E. McKenney
|
1d10bf55d8 |
rcu-tasks: Don't delete holdouts within trc_inspect_reader()
As Yanfei pointed out, although invoking trc_del_holdout() is safe from the viewpoint of the integrity of the holdout list itself, the put_task_struct() invoked by trc_del_holdout() can result in use-after-free errors due to later accesses to this task_struct structure by the RCU Tasks Trace grace-period kthread. This commit therefore removes this call to trc_del_holdout() from trc_inspect_reader() in favor of the grace-period thread's existing call to trc_del_holdout(), thus eliminating that particular class of use-after-free errors. Reported-by: "Xu, Yanfei" <yanfei.xu@windriver.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> |
||
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Paul E. McKenney
|
05bc276cf2 |
refscale: Avoid false-positive warnings in ref_scale_reader()
If the call to set_cpus_allowed_ptr() in ref_scale_reader()
fails, a later WARN_ONCE() complains. But with the advent of
|
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Paul E. McKenney
|
22b6d14992 |
scftorture: Avoid false-positive warnings in scftorture_invoker()
If the call to set_cpus_allowed_ptr() in scftorture_invoker()
fails, a later WARN_ONCE() complains. But with the advent of
|
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|
Linus Torvalds
|
df8ba5f160 |
Merge tag 'kgdb-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux
Pull kgdb updates from Daniel Thompson: "This was a extremely quiet cycle for kgdb. This consists of two patches that between them address spelling errors and a switch fallthrough warning" * tag 'kgdb-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux: kgdb: Fix fall-through warning for Clang kgdb: Fix spelling mistakes |
||
Peter Zijlstra
|
fa68bd09fc |
kprobe/static_call: Restore missing static_call_text_reserved()
Restore two hunks from commit: |
||
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Peter Zijlstra
|
2bee6d16e4 |
static_call: Fix static_call_text_reserved() vs __init
It turns out that static_call_text_reserved() was reporting __init
text as being reserved past the time when the __init text was freed
and re-used.
This is mostly harmless and will at worst result in refusing a kprobe.
Fixes:
|