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Add trace points for KVM RISC-V #18

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avpatel opened this issue Oct 13, 2020 · 0 comments
Open

Add trace points for KVM RISC-V #18

avpatel opened this issue Oct 13, 2020 · 0 comments
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avpatel commented Oct 13, 2020

Add trace points at interesting places in KVM RISC-V for gathering interesting stats.

Not started yet.

@avpatel avpatel added the enhancement New feature or request label Oct 13, 2020
@avpatel avpatel changed the title Add trace points Add trace points for KVM RISC-V Oct 13, 2020
avpatel pushed a commit that referenced this issue Oct 4, 2021
It's later supposed to be either a correct address or NULL. Without the
initialization, it may contain an undefined value which results in the
following segmentation fault:

  # perf top --sort comm -g --ignore-callees=do_idle

terminates with:

  #0  0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6
  #1  0x00007ffff55e3802 in strdup () from /lib64/libc.so.6
  #2  0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489
  #3  hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564
  #4  0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420,
      sample_self=sample_self@entry=true) at util/hist.c:657
  #5  0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0,
      sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288
  #6  0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38)
      at util/hist.c:1056
  #7  iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056
  #8  0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0)
      at util/hist.c:1231
  #9  0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0)
      at builtin-top.c:842
  #10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202
  #11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244
  #12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323
  #13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339
  #14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341
  #15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339
  #16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114
  #17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0
  #18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6

If you look at the frame #2, the code is:

488	 if (he->srcline) {
489          he->srcline = strdup(he->srcline);
490          if (he->srcline == NULL)
491              goto err_rawdata;
492	 }

If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish),
it gets strdupped and strdupping a rubbish random string causes the problem.

Also, if you look at the commit 1fb7d06, it adds the srcline property
into the struct, but not initializing it everywhere needed.

Committer notes:

Now I see, when using --ignore-callees=do_idle we end up here at line
2189 in add_callchain_ip():

2181         if (al.sym != NULL) {
2182                 if (perf_hpp_list.parent && !*parent &&
2183                     symbol__match_regex(al.sym, &parent_regex))
2184                         *parent = al.sym;
2185                 else if (have_ignore_callees && root_al &&
2186                   symbol__match_regex(al.sym, &ignore_callees_regex)) {
2187                         /* Treat this symbol as the root,
2188                            forgetting its callees. */
2189                         *root_al = al;
2190                         callchain_cursor_reset(cursor);
2191                 }
2192         }

And the al that doesn't have the ->srcline field initialized will be
copied to the root_al, so then, back to:

1211 int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
1212                          int max_stack_depth, void *arg)
1213 {
1214         int err, err2;
1215         struct map *alm = NULL;
1216
1217         if (al)
1218                 alm = map__get(al->map);
1219
1220         err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent,
1221                                         iter->evsel, al, max_stack_depth);
1222         if (err) {
1223                 map__put(alm);
1224                 return err;
1225         }
1226
1227         err = iter->ops->prepare_entry(iter, al);
1228         if (err)
1229                 goto out;
1230
1231         err = iter->ops->add_single_entry(iter, al);
1232         if (err)
1233                 goto out;
1234

That al at line 1221 is what hist_entry_iter__add() (called from
sample__resolve_callchain()) saw as 'root_al', and then:

        iter->ops->add_single_entry(iter, al);

will go on with al->srcline with a bogus value, I'll add the above
sequence to the cset and apply, thanks!

Signed-off-by: Michael Petlan <[email protected]>
CC: Milian Wolff <[email protected]>
Cc: Jiri Olsa <[email protected]>
Fixes: 1fb7d06 ("perf report Use srcline from callchain for hist entries")
Link: https //lore.kernel.org/r/[email protected]
Reported-by: Juri Lelli <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
avpatel pushed a commit that referenced this issue Dec 6, 2021
Possible recursive locking is detected by lockdep when SMC
falls back to TCP. The corresponding warnings are as follows:

 ============================================
 WARNING: possible recursive locking detected
 5.16.0-rc1+ #18 Tainted: G            E
 --------------------------------------------
 wrk/1391 is trying to acquire lock:
 ffff975246c8e7d8 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0x109/0x250 [smc]

 but task is already holding lock:
 ffff975246c8f918 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0xfe/0x250 [smc]

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&ei->socket.wq.wait);
   lock(&ei->socket.wq.wait);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 2 locks held by wrk/1391:
  #0: ffff975246040130 (sk_lock-AF_SMC){+.+.}-{0:0}, at: smc_connect+0x43/0x150 [smc]
  #1: ffff975246c8f918 (&ei->socket.wq.wait){..-.}-{3:3}, at: smc_switch_to_fallback+0xfe/0x250 [smc]

 stack backtrace:
 Call Trace:
  <TASK>
  dump_stack_lvl+0x56/0x7b
  __lock_acquire+0x951/0x11f0
  lock_acquire+0x27a/0x320
  ? smc_switch_to_fallback+0x109/0x250 [smc]
  ? smc_switch_to_fallback+0xfe/0x250 [smc]
  _raw_spin_lock_irq+0x3b/0x80
  ? smc_switch_to_fallback+0x109/0x250 [smc]
  smc_switch_to_fallback+0x109/0x250 [smc]
  smc_connect_fallback+0xe/0x30 [smc]
  __smc_connect+0xcf/0x1090 [smc]
  ? mark_held_locks+0x61/0x80
  ? __local_bh_enable_ip+0x77/0xe0
  ? lockdep_hardirqs_on+0xbf/0x130
  ? smc_connect+0x12a/0x150 [smc]
  smc_connect+0x12a/0x150 [smc]
  __sys_connect+0x8a/0xc0
  ? syscall_enter_from_user_mode+0x20/0x70
  __x64_sys_connect+0x16/0x20
  do_syscall_64+0x34/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae

The nested locking in smc_switch_to_fallback() is considered to
possibly cause a deadlock because smc_wait->lock and clc_wait->lock
are the same type of lock. But actually it is safe so far since
there is no other place trying to obtain smc_wait->lock when
clc_wait->lock is held. So the patch replaces spin_lock() with
spin_lock_nested() to avoid false report by lockdep.

Link: https://lkml.org/lkml/2021/11/19/962
Fixes: 2153bd1 ("Transfer remaining wait queue entries during fallback")
Reported-by: [email protected]
Signed-off-by: Wen Gu <[email protected]>
Acked-by: Tony Lu <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
avpatel pushed a commit that referenced this issue Feb 28, 2022
When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
avpatel pushed a commit that referenced this issue Jun 7, 2022
syscall_stub_data() expects the data_count parameter to be the number of
longs, not bytes.

 ==================================================================
 BUG: KASAN: stack-out-of-bounds in syscall_stub_data+0x70/0xe0
 Read of size 128 at addr 000000006411f6f0 by task swapper/1

 CPU: 0 PID: 1 Comm: swapper Not tainted 5.18.0+ #18
 Call Trace:
  show_stack.cold+0x166/0x2a7
  __dump_stack+0x3a/0x43
  dump_stack_lvl+0x1f/0x27
  print_report.cold+0xdb/0xf81
  kasan_report+0x119/0x1f0
  kasan_check_range+0x3a3/0x440
  memcpy+0x52/0x140
  syscall_stub_data+0x70/0xe0
  write_ldt_entry+0xac/0x190
  init_new_ldt+0x515/0x960
  init_new_context+0x2c4/0x4d0
  mm_init.constprop.0+0x5ed/0x760
  mm_alloc+0x118/0x170
  0x60033f48
  do_one_initcall+0x1d7/0x860
  0x60003e7b
  kernel_init+0x6e/0x3d4
  new_thread_handler+0x1e7/0x2c0

 The buggy address belongs to stack of task swapper/1
  and is located at offset 64 in frame:
  init_new_ldt+0x0/0x960

 This frame has 2 objects:
  [32, 40) 'addr'
  [64, 80) 'desc'
 ==================================================================

Fixes: 858259c ("uml: maintain own LDT entries")
Signed-off-by: Vincent Whitchurch <[email protected]>
Cc: [email protected]
Signed-off-by: Richard Weinberger <[email protected]>
avpatel pushed a commit that referenced this issue Nov 28, 2022
In __unregister_kprobe_top(), if the currently unregistered probe has
post_handler but other child probes of the aggrprobe do not have
post_handler, the post_handler of the aggrprobe is cleared. If this is
a ftrace-based probe, there is a problem. In later calls to
disarm_kprobe(), we will use kprobe_ftrace_ops because post_handler is
NULL. But we're armed with kprobe_ipmodify_ops. This triggers a WARN in
__disarm_kprobe_ftrace() and may even cause use-after-free:

  Failed to disarm kprobe-ftrace at kernel_clone+0x0/0x3c0 (error -2)
  WARNING: CPU: 5 PID: 137 at kernel/kprobes.c:1135 __disarm_kprobe_ftrace.isra.21+0xcf/0xe0
  Modules linked in: testKprobe_007(-)
  CPU: 5 PID: 137 Comm: rmmod Not tainted 6.1.0-rc4-dirty #18
  [...]
  Call Trace:
   <TASK>
   __disable_kprobe+0xcd/0xe0
   __unregister_kprobe_top+0x12/0x150
   ? mutex_lock+0xe/0x30
   unregister_kprobes.part.23+0x31/0xa0
   unregister_kprobe+0x32/0x40
   __x64_sys_delete_module+0x15e/0x260
   ? do_user_addr_fault+0x2cd/0x6b0
   do_syscall_64+0x3a/0x90
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
   [...]

For the kprobe-on-ftrace case, we keep the post_handler setting to
identify this aggrprobe armed with kprobe_ipmodify_ops. This way we
can disarm it correctly.

Link: https://lore.kernel.org/all/[email protected]/

Fixes: 0bc11ed ("kprobes: Allow kprobes coexist with livepatch")
Reported-by: Zhao Gongyi <[email protected]>
Suggested-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Li Huafei <[email protected]>
Acked-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
avpatel pushed a commit that referenced this issue Jan 19, 2023
The inline assembly for arm64's cmpxchg_double*() implementations use a
+Q constraint to hazard against other accesses to the memory location
being exchanged. However, the pointer passed to the constraint is a
pointer to unsigned long, and thus the hazard only applies to the first
8 bytes of the location.

GCC can take advantage of this, assuming that other portions of the
location are unchanged, leading to a number of potential problems.

This is similar to what we fixed back in commit:

  fee960b ("arm64: xchg: hazard against entire exchange variable")

... but we forgot to adjust cmpxchg_double*() similarly at the same
time.

The same problem applies, as demonstrated with the following test:

| struct big {
|         u64 lo, hi;
| } __aligned(128);
|
| unsigned long foo(struct big *b)
| {
|         u64 hi_old, hi_new;
|
|         hi_old = b->hi;
|         cmpxchg_double_local(&b->lo, &b->hi, 0x12, 0x34, 0x56, 0x78);
|         hi_new = b->hi;
|
|         return hi_old ^ hi_new;
| }

... which GCC 12.1.0 compiles as:

| 0000000000000000 <foo>:
|    0:   d503233f        paciasp
|    4:   aa0003e4        mov     x4, x0
|    8:   1400000e        b       40 <foo+0x40>
|    c:   d2800240        mov     x0, #0x12                       // #18
|   10:   d2800681        mov     x1, #0x34                       // #52
|   14:   aa0003e5        mov     x5, x0
|   18:   aa0103e6        mov     x6, x1
|   1c:   d2800ac2        mov     x2, #0x56                       // #86
|   20:   d2800f03        mov     x3, #0x78                       // #120
|   24:   48207c82        casp    x0, x1, x2, x3, [x4]
|   28:   ca050000        eor     x0, x0, x5
|   2c:   ca060021        eor     x1, x1, x6
|   30:   aa010000        orr     x0, x0, x1
|   34:   d2800000        mov     x0, #0x0                        // #0    <--- BANG
|   38:   d50323bf        autiasp
|   3c:   d65f03c0        ret
|   40:   d2800240        mov     x0, #0x12                       // #18
|   44:   d2800681        mov     x1, #0x34                       // #52
|   48:   d2800ac2        mov     x2, #0x56                       // #86
|   4c:   d2800f03        mov     x3, #0x78                       // #120
|   50:   f9800091        prfm    pstl1strm, [x4]
|   54:   c87f1885        ldxp    x5, x6, [x4]
|   58:   ca0000a5        eor     x5, x5, x0
|   5c:   ca0100c6        eor     x6, x6, x1
|   60:   aa0600a6        orr     x6, x5, x6
|   64:   b5000066        cbnz    x6, 70 <foo+0x70>
|   68:   c8250c82        stxp    w5, x2, x3, [x4]
|   6c:   35ffff45        cbnz    w5, 54 <foo+0x54>
|   70:   d2800000        mov     x0, #0x0                        // #0     <--- BANG
|   74:   d50323bf        autiasp
|   78:   d65f03c0        ret

Notice that at the lines with "BANG" comments, GCC has assumed that the
higher 8 bytes are unchanged by the cmpxchg_double() call, and that
`hi_old ^ hi_new` can be reduced to a constant zero, for both LSE and
LL/SC versions of cmpxchg_double().

This patch fixes the issue by passing a pointer to __uint128_t into the
+Q constraint, ensuring that the compiler hazards against the entire 16
bytes being modified.

With this change, GCC 12.1.0 compiles the above test as:

| 0000000000000000 <foo>:
|    0:   f9400407        ldr     x7, [x0, #8]
|    4:   d503233f        paciasp
|    8:   aa0003e4        mov     x4, x0
|    c:   1400000f        b       48 <foo+0x48>
|   10:   d2800240        mov     x0, #0x12                       // #18
|   14:   d2800681        mov     x1, #0x34                       // #52
|   18:   aa0003e5        mov     x5, x0
|   1c:   aa0103e6        mov     x6, x1
|   20:   d2800ac2        mov     x2, #0x56                       // #86
|   24:   d2800f03        mov     x3, #0x78                       // #120
|   28:   48207c82        casp    x0, x1, x2, x3, [x4]
|   2c:   ca050000        eor     x0, x0, x5
|   30:   ca060021        eor     x1, x1, x6
|   34:   aa010000        orr     x0, x0, x1
|   38:   f9400480        ldr     x0, [x4, #8]
|   3c:   d50323bf        autiasp
|   40:   ca0000e0        eor     x0, x7, x0
|   44:   d65f03c0        ret
|   48:   d2800240        mov     x0, #0x12                       // #18
|   4c:   d2800681        mov     x1, #0x34                       // #52
|   50:   d2800ac2        mov     x2, #0x56                       // #86
|   54:   d2800f03        mov     x3, #0x78                       // #120
|   58:   f9800091        prfm    pstl1strm, [x4]
|   5c:   c87f1885        ldxp    x5, x6, [x4]
|   60:   ca0000a5        eor     x5, x5, x0
|   64:   ca0100c6        eor     x6, x6, x1
|   68:   aa0600a6        orr     x6, x5, x6
|   6c:   b5000066        cbnz    x6, 78 <foo+0x78>
|   70:   c8250c82        stxp    w5, x2, x3, [x4]
|   74:   35ffff45        cbnz    w5, 5c <foo+0x5c>
|   78:   f9400480        ldr     x0, [x4, #8]
|   7c:   d50323bf        autiasp
|   80:   ca0000e0        eor     x0, x7, x0
|   84:   d65f03c0        ret

... sampling the high 8 bytes before and after the cmpxchg, and
performing an EOR, as we'd expect.

For backporting, I've tested this atop linux-4.9.y with GCC 5.5.0. Note
that linux-4.9.y is oldest currently supported stable release, and
mandates GCC 5.1+. Unfortunately I couldn't get a GCC 5.1 binary to run
on my machines due to library incompatibilities.

I've also used a standalone test to check that we can use a __uint128_t
pointer in a +Q constraint at least as far back as GCC 4.8.5 and LLVM
3.9.1.

Fixes: 5284e1b ("arm64: xchg: Implement cmpxchg_double")
Fixes: e9a4b79 ("arm64: cmpxchg_dbl: patch in lse instructions when supported by the CPU")
Reported-by: Boqun Feng <[email protected]>
Link: https://lore.kernel.org/lkml/Y6DEfQXymYVgL3oJ@boqun-archlinux/
Reported-by: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]/
Signed-off-by: Mark Rutland <[email protected]>
Cc: [email protected]
Cc: Arnd Bergmann <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Steve Capper <[email protected]>
Cc: Will Deacon <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
avpatel pushed a commit that referenced this issue Mar 27, 2023
WED is supported just for mmio devices, so do not check it for usb or
sdio devices. This patch fixes the crash reported below:

[   21.946627] wlp0s3u1i3: authenticate with c4:41:1e:f5:2b:1d
[   22.525298] wlp0s3u1i3: send auth to c4:41:1e:f5:2b:1d (try 1/3)
[   22.548274] wlp0s3u1i3: authenticate with c4:41:1e:f5:2b:1d
[   22.557694] wlp0s3u1i3: send auth to c4:41:1e:f5:2b:1d (try 1/3)
[   22.565885] wlp0s3u1i3: authenticated
[   22.569502] wlp0s3u1i3: associate with c4:41:1e:f5:2b:1d (try 1/3)
[   22.578966] wlp0s3u1i3: RX AssocResp from c4:41:1e:f5:2b:1d (capab=0x11 status=30 aid=3)
[   22.579113] wlp0s3u1i3: c4:41:1e:f5:2b:1d rejected association temporarily; comeback duration 1000 TU (1024 ms)
[   23.649518] wlp0s3u1i3: associate with c4:41:1e:f5:2b:1d (try 2/3)
[   23.752528] wlp0s3u1i3: RX AssocResp from c4:41:1e:f5:2b:1d (capab=0x11 status=0 aid=3)
[   23.797450] wlp0s3u1i3: associated
[   24.959527] kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
[   24.959640] BUG: unable to handle page fault for address: ffff88800c223200
[   24.959706] #PF: supervisor instruction fetch in kernel mode
[   24.959788] #PF: error_code(0x0011) - permissions violation
[   24.959846] PGD 2c01067 P4D 2c01067 PUD 2c02067 PMD c2a8063 PTE 800000000c223163
[   24.959957] Oops: 0011 [#1] PREEMPT SMP
[   24.960009] CPU: 0 PID: 391 Comm: wpa_supplicant Not tainted 6.2.0-kvm #18
[   24.960089] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.1-2.fc37 04/01/2014
[   24.960191] RIP: 0010:0xffff88800c223200
[   24.960446] RSP: 0018:ffffc90000ff7698 EFLAGS: 00010282
[   24.960513] RAX: ffff888028397010 RBX: ffff88800c26e630 RCX: 0000000000000058
[   24.960598] RDX: ffff88800c26f844 RSI: 0000000000000006 RDI: ffff888028397010
[   24.960682] RBP: ffff88800ea72f00 R08: 18b873fbab2b964c R09: be06b38235f3c63c
[   24.960766] R10: 18b873fbab2b964c R11: be06b38235f3c63c R12: 0000000000000001
[   24.960853] R13: ffff88800c26f84c R14: ffff8880063f0ff8 R15: ffff88800c26e644
[   24.960950] FS:  00007effcea327c0(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000
[   24.961036] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   24.961106] CR2: ffff88800c223200 CR3: 000000000eaa2000 CR4: 00000000000006b0
[   24.961190] Call Trace:
[   24.961219]  <TASK>
[   24.961245]  ? mt76_connac_mcu_add_key+0x2cf/0x310
[   24.961313]  ? mt7921_set_key+0x150/0x200
[   24.961365]  ? drv_set_key+0xa9/0x1b0
[   24.961418]  ? ieee80211_key_enable_hw_accel+0xd9/0x240
[   24.961485]  ? ieee80211_key_replace+0x3f3/0x730
[   24.961541]  ? crypto_shash_setkey+0x89/0xd0
[   24.961597]  ? ieee80211_key_link+0x2d7/0x3a0
[   24.961664]  ? crypto_aead_setauthsize+0x31/0x50
[   24.961730]  ? sta_info_hash_lookup+0xa6/0xf0
[   24.961785]  ? ieee80211_add_key+0x1fc/0x250
[   24.961842]  ? rdev_add_key+0x41/0x140
[   24.961882]  ? nl80211_parse_key+0x6c/0x2f0
[   24.961940]  ? nl80211_new_key+0x24a/0x290
[   24.961984]  ? genl_rcv_msg+0x36c/0x3a0
[   24.962036]  ? rdev_mod_link_station+0xe0/0xe0
[   24.962102]  ? nl80211_set_key+0x410/0x410
[   24.962143]  ? nl80211_pre_doit+0x200/0x200
[   24.962187]  ? genl_bind+0xc0/0xc0
[   24.962217]  ? netlink_rcv_skb+0xaa/0xd0
[   24.962259]  ? genl_rcv+0x24/0x40
[   24.962300]  ? netlink_unicast+0x224/0x2f0
[   24.962345]  ? netlink_sendmsg+0x30b/0x3d0
[   24.962388]  ? ____sys_sendmsg+0x109/0x1b0
[   24.962388]  ? ____sys_sendmsg+0x109/0x1b0
[   24.962440]  ? __import_iovec+0x2e/0x110
[   24.962482]  ? ___sys_sendmsg+0xbe/0xe0
[   24.962525]  ? mod_objcg_state+0x25c/0x330
[   24.962576]  ? __dentry_kill+0x19e/0x1d0
[   24.962618]  ? call_rcu+0x18f/0x270
[   24.962660]  ? __dentry_kill+0x19e/0x1d0
[   24.962702]  ? __x64_sys_sendmsg+0x70/0x90
[   24.962744]  ? do_syscall_64+0x3d/0x80
[   24.962796]  ? exit_to_user_mode_prepare+0x1b/0x70
[   24.962852]  ? entry_SYSCALL_64_after_hwframe+0x46/0xb0
[   24.962913]  </TASK>
[   24.962939] Modules linked in:
[   24.962981] CR2: ffff88800c223200
[   24.963022] ---[ end trace 0000000000000000 ]---
[   24.963087] RIP: 0010:0xffff88800c223200
[   24.963323] RSP: 0018:ffffc90000ff7698 EFLAGS: 00010282
[   24.963376] RAX: ffff888028397010 RBX: ffff88800c26e630 RCX: 0000000000000058
[   24.963458] RDX: ffff88800c26f844 RSI: 0000000000000006 RDI: ffff888028397010
[   24.963538] RBP: ffff88800ea72f00 R08: 18b873fbab2b964c R09: be06b38235f3c63c
[   24.963622] R10: 18b873fbab2b964c R11: be06b38235f3c63c R12: 0000000000000001
[   24.963705] R13: ffff88800c26f84c R14: ffff8880063f0ff8 R15: ffff88800c26e644
[   24.963788] FS:  00007effcea327c0(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000
[   24.963871] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   24.963941] CR2: ffff88800c223200 CR3: 000000000eaa2000 CR4: 00000000000006b0
[   24.964018] note: wpa_supplicant[391] exited with irqs disabled

Fixes: d1369e5 ("wifi: mt76: connac: introduce mt76_connac_mcu_sta_wed_update utility routine")
Signed-off-by: Lorenzo Bianconi <[email protected]>
Acked-by: Felix Fietkau <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://lore.kernel.org/r/c42168429453474213fa8244bf4b069de4531f40.1678124335.git.lorenzo@kernel.org
avpatel pushed a commit that referenced this issue Mar 27, 2023
When a system with E810 with existing VFs gets rebooted the following
hang may be observed.

 Pid 1 is hung in iavf_remove(), part of a network driver:
 PID: 1        TASK: ffff965400e5a340  CPU: 24   COMMAND: "systemd-shutdow"
  #0 [ffffaad04005fa50] __schedule at ffffffff8b3239cb
  #1 [ffffaad04005fae8] schedule at ffffffff8b323e2d
  #2 [ffffaad04005fb00] schedule_hrtimeout_range_clock at ffffffff8b32cebc
  #3 [ffffaad04005fb80] usleep_range_state at ffffffff8b32c930
  #4 [ffffaad04005fbb0] iavf_remove at ffffffffc12b9b4c [iavf]
  #5 [ffffaad04005fbf0] pci_device_remove at ffffffff8add7513
  #6 [ffffaad04005fc10] device_release_driver_internal at ffffffff8af08baa
  #7 [ffffaad04005fc40] pci_stop_bus_device at ffffffff8adcc5fc
  #8 [ffffaad04005fc60] pci_stop_and_remove_bus_device at ffffffff8adcc81e
  #9 [ffffaad04005fc70] pci_iov_remove_virtfn at ffffffff8adf9429
 #10 [ffffaad04005fca8] sriov_disable at ffffffff8adf98e4
 #11 [ffffaad04005fcc8] ice_free_vfs at ffffffffc04bb2c8 [ice]
 #12 [ffffaad04005fd10] ice_remove at ffffffffc04778fe [ice]
 #13 [ffffaad04005fd38] ice_shutdown at ffffffffc0477946 [ice]
 #14 [ffffaad04005fd50] pci_device_shutdown at ffffffff8add58f1
 #15 [ffffaad04005fd70] device_shutdown at ffffffff8af05386
 #16 [ffffaad04005fd98] kernel_restart at ffffffff8a92a870
 #17 [ffffaad04005fda8] __do_sys_reboot at ffffffff8a92abd6
 #18 [ffffaad04005fee0] do_syscall_64 at ffffffff8b317159
 #19 [ffffaad04005ff08] __context_tracking_enter at ffffffff8b31b6fc
 #20 [ffffaad04005ff18] syscall_exit_to_user_mode at ffffffff8b31b50d
 #21 [ffffaad04005ff28] do_syscall_64 at ffffffff8b317169
 #22 [ffffaad04005ff50] entry_SYSCALL_64_after_hwframe at ffffffff8b40009b
     RIP: 00007f1baa5c13d7  RSP: 00007fffbcc55a98  RFLAGS: 00000202
     RAX: ffffffffffffffda  RBX: 0000000000000000  RCX: 00007f1baa5c13d7
     RDX: 0000000001234567  RSI: 0000000028121969  RDI: 00000000fee1dead
     RBP: 00007fffbcc55ca0   R8: 0000000000000000   R9: 00007fffbcc54e90
     R10: 00007fffbcc55050  R11: 0000000000000202  R12: 0000000000000005
     R13: 0000000000000000  R14: 00007fffbcc55af0  R15: 0000000000000000
     ORIG_RAX: 00000000000000a9  CS: 0033  SS: 002b

During reboot all drivers PM shutdown callbacks are invoked.
In iavf_shutdown() the adapter state is changed to __IAVF_REMOVE.
In ice_shutdown() the call chain above is executed, which at some point
calls iavf_remove(). However iavf_remove() expects the VF to be in one
of the states __IAVF_RUNNING, __IAVF_DOWN or __IAVF_INIT_FAILED. If
that's not the case it sleeps forever.
So if iavf_shutdown() gets invoked before iavf_remove() the system will
hang indefinitely because the adapter is already in state __IAVF_REMOVE.

Fix this by returning from iavf_remove() if the state is __IAVF_REMOVE,
as we already went through iavf_shutdown().

Fixes: 9745780 ("iavf: Add waiting so the port is initialized in remove")
Fixes: a841733 ("iavf: Fix race condition between iavf_shutdown and iavf_remove")
Reported-by: Marius Cornea <[email protected]>
Signed-off-by: Stefan Assmann <[email protected]>
Reviewed-by: Michal Kubiak <[email protected]>
Tested-by: Rafal Romanowski <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>
avpatel pushed a commit that referenced this issue Jun 5, 2023
The cited commit adds a compeletion to remove dependency on rtnl
lock. But it causes a deadlock for multiple encapsulations:

 crash> bt ffff8aece8a64000
 PID: 1514557  TASK: ffff8aece8a64000  CPU: 3    COMMAND: "tc"
  #0 [ffffa6d14183f368] __schedule at ffffffffb8ba7f45
  #1 [ffffa6d14183f3f8] schedule at ffffffffb8ba8418
  #2 [ffffa6d14183f418] schedule_preempt_disabled at ffffffffb8ba8898
  #3 [ffffa6d14183f428] __mutex_lock at ffffffffb8baa7f8
  #4 [ffffa6d14183f4d0] mutex_lock_nested at ffffffffb8baabeb
  #5 [ffffa6d14183f4e0] mlx5e_attach_encap at ffffffffc0f48c17 [mlx5_core]
  #6 [ffffa6d14183f628] mlx5e_tc_add_fdb_flow at ffffffffc0f39680 [mlx5_core]
  #7 [ffffa6d14183f688] __mlx5e_add_fdb_flow at ffffffffc0f3b636 [mlx5_core]
  #8 [ffffa6d14183f6f0] mlx5e_tc_add_flow at ffffffffc0f3bcdf [mlx5_core]
  #9 [ffffa6d14183f728] mlx5e_configure_flower at ffffffffc0f3c1d1 [mlx5_core]
 #10 [ffffa6d14183f790] mlx5e_rep_setup_tc_cls_flower at ffffffffc0f3d529 [mlx5_core]
 #11 [ffffa6d14183f7a0] mlx5e_rep_setup_tc_cb at ffffffffc0f3d714 [mlx5_core]
 #12 [ffffa6d14183f7b0] tc_setup_cb_add at ffffffffb8931bb8
 #13 [ffffa6d14183f810] fl_hw_replace_filter at ffffffffc0dae901 [cls_flower]
 #14 [ffffa6d14183f8d8] fl_change at ffffffffc0db5c57 [cls_flower]
 #15 [ffffa6d14183f970] tc_new_tfilter at ffffffffb8936047
 #16 [ffffa6d14183fac8] rtnetlink_rcv_msg at ffffffffb88c7c31
 #17 [ffffa6d14183fb50] netlink_rcv_skb at ffffffffb8942853
 #18 [ffffa6d14183fbc0] rtnetlink_rcv at ffffffffb88c1835
 #19 [ffffa6d14183fbd0] netlink_unicast at ffffffffb8941f27
 #20 [ffffa6d14183fc18] netlink_sendmsg at ffffffffb8942245
 #21 [ffffa6d14183fc98] sock_sendmsg at ffffffffb887d482
 #22 [ffffa6d14183fcb8] ____sys_sendmsg at ffffffffb887d81a
 #23 [ffffa6d14183fd38] ___sys_sendmsg at ffffffffb88806e2
 #24 [ffffa6d14183fe90] __sys_sendmsg at ffffffffb88807a2
 #25 [ffffa6d14183ff28] __x64_sys_sendmsg at ffffffffb888080f
 #26 [ffffa6d14183ff38] do_syscall_64 at ffffffffb8b9b6a8
 #27 [ffffa6d14183ff50] entry_SYSCALL_64_after_hwframe at ffffffffb8c0007c
 crash> bt 0xffff8aeb07544000
 PID: 1110766  TASK: ffff8aeb07544000  CPU: 0    COMMAND: "kworker/u20:9"
  #0 [ffffa6d14e6b7bd8] __schedule at ffffffffb8ba7f45
  #1 [ffffa6d14e6b7c68] schedule at ffffffffb8ba8418
  #2 [ffffa6d14e6b7c88] schedule_timeout at ffffffffb8baef88
  #3 [ffffa6d14e6b7d10] wait_for_completion at ffffffffb8ba968b
  #4 [ffffa6d14e6b7d60] mlx5e_take_all_encap_flows at ffffffffc0f47ec4 [mlx5_core]
  #5 [ffffa6d14e6b7da0] mlx5e_rep_update_flows at ffffffffc0f3e734 [mlx5_core]
  #6 [ffffa6d14e6b7df8] mlx5e_rep_neigh_update at ffffffffc0f400bb [mlx5_core]
  #7 [ffffa6d14e6b7e50] process_one_work at ffffffffb80acc9c
  #8 [ffffa6d14e6b7ed0] worker_thread at ffffffffb80ad012
  #9 [ffffa6d14e6b7f10] kthread at ffffffffb80b615d
 #10 [ffffa6d14e6b7f50] ret_from_fork at ffffffffb8001b2f

After the first encap is attached, flow will be added to encap
entry's flows list. If neigh update is running at this time, the
following encaps of the flow can't hold the encap_tbl_lock and
sleep. If neigh update thread is waiting for that flow's init_done,
deadlock happens.

Fix it by holding lock outside of the for loop. If neigh update is
running, prevent encap flows from offloading. Since the lock is held
outside of the for loop, concurrent creation of encap entries is not
allowed. So remove unnecessary wait_for_completion call for res_ready.

Fixes: 95435ad ("net/mlx5e: Only access fully initialized flows in neigh update")
Signed-off-by: Chris Mi <[email protected]>
Reviewed-by: Roi Dayan <[email protected]>
Reviewed-by: Vlad Buslov <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>
avpatel pushed a commit that referenced this issue Sep 18, 2023
The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Mike Christie <[email protected]>
Cc: [email protected]
Signed-off-by: Martin K. Petersen <[email protected]>
avpatel pushed a commit that referenced this issue Oct 9, 2023
The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Mike Christie <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
avpatel pushed a commit that referenced this issue Dec 13, 2023
When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   #15 [ffff88aa841efb88] device_del at ffffffff82179d23
   #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   #20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/[email protected]
Suggested-by: "Ismail, Mustafa" <[email protected]>
Signed-off-by: Shifeng Li <[email protected]>
Reviewed-by: Shiraz Saleem <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
avpatel pushed a commit that referenced this issue Apr 8, 2024
sg_init_one() relies on linearly mapped low memory for the safe
utilization of virt_to_page().  Otherwise, we trigger a kernel BUG,

kernel BUG at include/linux/scatterlist.h:187!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 2997 Comm: syz-executor198 Not tainted 6.8.0-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at sg_set_buf include/linux/scatterlist.h:187 [inline]
PC is at sg_init_one+0x9c/0xa8 lib/scatterlist.c:143
LR is at sg_init_table+0x2c/0x40 lib/scatterlist.c:128
Backtrace:
[<807e16ac>] (sg_init_one) from [<804c1824>] (zswap_decompress+0xbc/0x208 mm/zswap.c:1089)
 r7:83471c80 r6:def6d08c r5:844847d0 r4:ff7e7ef4
[<804c1768>] (zswap_decompress) from [<804c4468>] (zswap_load+0x15c/0x198 mm/zswap.c:1637)
 r9:8446eb80 r8:8446eb80 r7:8446eb84 r6:def6d08c r5:00000001 r4:844847d0
[<804c430c>] (zswap_load) from [<804b9644>] (swap_read_folio+0xa8/0x498 mm/page_io.c:518)
 r9:844ac800 r8:835e6c00 r7:00000000 r6:df955d4c r5:00000001 r4:def6d08c
[<804b959c>] (swap_read_folio) from [<804bb064>] (swap_cluster_readahead+0x1c4/0x34c mm/swap_state.c:684)
 r10:00000000 r9:00000007 r8:df955d4b r7:00000000 r6:00000000 r5:00100cca
 r4:00000001
[<804baea0>] (swap_cluster_readahead) from [<804bb3b8>] (swapin_readahead+0x68/0x4a8 mm/swap_state.c:904)
 r10:df955eb8 r9:00000000 r8:00100cca r7:84476480 r6:00000001 r5:00000000
 r4:00000001
[<804bb350>] (swapin_readahead) from [<8047cde0>] (do_swap_page+0x200/0xcc4 mm/memory.c:4046)
 r10:00000040 r9:00000000 r8:844ac800 r7:84476480 r6:00000001 r5:00000000
 r4:df955eb8
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (handle_pte_fault mm/memory.c:5301 [inline])
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (__handle_mm_fault mm/memory.c:5439 [inline])
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (handle_mm_fault+0x3d8/0x12b8 mm/memory.c:5604)
 r10:00000040 r9:842b3900 r8:7eb0d000 r7:84476480 r6:7eb0d000 r5:835e6c00
 r4:00000254
[<8047e2ec>] (handle_mm_fault) from [<80215d28>] (do_page_fault+0x148/0x3a8 arch/arm/mm/fault.c:326)
 r10:00000007 r9:842b3900 r8:7eb0d000 r7:00000207 r6:00000254 r5:7eb0d9b4
 r4:df955fb0
[<80215be0>] (do_page_fault) from [<80216170>] (do_DataAbort+0x38/0xa8 arch/arm/mm/fault.c:558)
 r10:7eb0da7c r9:00000000 r8:80215be0 r7:df955fb0 r6:7eb0d9b4 r5:00000207
 r4:8261d0e0
[<80216138>] (do_DataAbort) from [<80200e3c>] (__dabt_usr+0x5c/0x60 arch/arm/kernel/entry-armv.S:427)
Exception stack(0xdf955fb0 to 0xdf955ff8)
5fa0:                                     00000000 00000000 22d5f800 0008d158
5fc0: 00000000 7eb0d9a4 00000000 00000109 00000000 00000000 7eb0da7c 7eb0da3c
5fe0: 00000000 7eb0d9a0 00000001 00066bd4 00000010 ffffffff
 r8:824a9044 r7:835e6c00 r6:ffffffff r5:00000010 r4:00066bd4
Code: 1a000004 e1822003 e8860094 e89da8f0 (e7f001f2)
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	1a000004 	bne	0x18
   4:	e1822003 	orr	r2, r2, r3
   8:	e8860094 	stm	r6, {r2, r4, r7}
   c:	e89da8f0 	ldm	sp, {r4, r5, r6, r7, fp, sp, pc}
* 10:	e7f001f2 	udf	#18 <-- trapping instruction

Consequently, we have two choices: either employ kmap_to_page() alongside
sg_set_page(), or resort to copying high memory contents to a temporary
buffer residing in low memory.  However, considering the introduction of
the WARN_ON_ONCE in commit ef6e06b ("highmem: fix kmap_to_page() for
kmap_local_page() addresses"), which specifically addresses high memory
concerns, it appears that memcpy remains the sole viable option.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 270700d ("mm/zswap: remove the memcpy if acomp is not sleepable")
Signed-off-by: Barry Song <[email protected]>
Reported-by: [email protected]
Closes: https://lore.kernel.org/all/[email protected]/
Tested-by: [email protected]
Acked-by: Yosry Ahmed <[email protected]>
Reviewed-by: Nhat Pham <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Cc: Chris Li <[email protected]>
Cc: Ira Weiny <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
avpatel pushed a commit that referenced this issue May 13, 2024
vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <[email protected]>
Reviewed-by: Willem de Bruijn <[email protected]>
Acked-by: Jason Wang <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
avpatel pushed a commit that referenced this issue May 27, 2024
…rnel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

Patch #1 skips transaction if object type provides no .update interface.

Patch #2 skips NETDEV_CHANGENAME which is unused.

Patch #3 enables conntrack to handle Multicast Router Advertisements and
	 Multicast Router Solicitations from the Multicast Router Discovery
	 protocol (RFC4286) as untracked opposed to invalid packets.
	 From Linus Luessing.

Patch #4 updates DCCP conntracker to mark invalid as invalid, instead of
	 dropping them, from Jason Xing.

Patch #5 uses NF_DROP instead of -NF_DROP since NF_DROP is 0,
	 also from Jason.

Patch #6 removes reference in netfilter's sysctl documentation on pickup
	 entries which were already removed by Florian Westphal.

Patch #7 removes check for IPS_OFFLOAD flag to disable early drop which
	 allows to evict entries from the conntrack table,
	 also from Florian.

Patches #8 to #16 updates nf_tables pipapo set backend to allocate
	 the datastructure copy on-demand from preparation phase,
	 to better deal with OOM situations where .commit step is too late
	 to fail. Series from Florian Westphal.

Patch #17 adds a selftest with packetdrill to cover conntrack TCP state
	 transitions, also from Florian.

Patch #18 use GFP_KERNEL to clone elements from control plane to avoid
	 quick atomic reserves exhaustion with large sets, reporter refers
	 to million entries magnitude.

* tag 'nf-next-24-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: allow clone callbacks to sleep
  selftests: netfilter: add packetdrill based conntrack tests
  netfilter: nft_set_pipapo: remove dirty flag
  netfilter: nft_set_pipapo: move cloning of match info to insert/removal path
  netfilter: nft_set_pipapo: prepare pipapo_get helper for on-demand clone
  netfilter: nft_set_pipapo: merge deactivate helper into caller
  netfilter: nft_set_pipapo: prepare walk function for on-demand clone
  netfilter: nft_set_pipapo: prepare destroy function for on-demand clone
  netfilter: nft_set_pipapo: make pipapo_clone helper return NULL
  netfilter: nft_set_pipapo: move prove_locking helper around
  netfilter: conntrack: remove flowtable early-drop test
  netfilter: conntrack: documentation: remove reference to non-existent sysctl
  netfilter: use NF_DROP instead of -NF_DROP
  netfilter: conntrack: dccp: try not to drop skb in conntrack
  netfilter: conntrack: fix ct-state for ICMPv6 Multicast Router Discovery
  netfilter: nf_tables: remove NETDEV_CHANGENAME from netdev chain event handler
  netfilter: nf_tables: skip transaction if update object is not implemented
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
avpatel pushed a commit that referenced this issue Jul 19, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
avpatel pushed a commit that referenced this issue Jul 19, 2024
When running BPF selftests (./test_progs -t sockmap_basic) on a Loongarch
platform, the following kernel panic occurs:

  [...]
  Oops[#1]:
  CPU: 22 PID: 2824 Comm: test_progs Tainted: G           OE  6.10.0-rc2+ #18
  Hardware name: LOONGSON Dabieshan/Loongson-TC542F0, BIOS Loongson-UDK2018
     ... ...
     ra: 90000000048bf6c0 sk_msg_recvmsg+0x120/0x560
    ERA: 9000000004162774 copy_page_to_iter+0x74/0x1c0
   CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
   PRMD: 0000000c (PPLV0 +PIE +PWE)
   EUEN: 00000007 (+FPE +SXE +ASXE -BTE)
   ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7)
  ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
   BADV: 0000000000000040
   PRID: 0014c011 (Loongson-64bit, Loongson-3C5000)
  Modules linked in: bpf_testmod(OE) xt_CHECKSUM xt_MASQUERADE xt_conntrack
  Process test_progs (pid: 2824, threadinfo=0000000000863a31, task=...)
  Stack : ...
  Call Trace:
  [<9000000004162774>] copy_page_to_iter+0x74/0x1c0
  [<90000000048bf6c0>] sk_msg_recvmsg+0x120/0x560
  [<90000000049f2b90>] tcp_bpf_recvmsg_parser+0x170/0x4e0
  [<90000000049aae34>] inet_recvmsg+0x54/0x100
  [<900000000481ad5c>] sock_recvmsg+0x7c/0xe0
  [<900000000481e1a8>] __sys_recvfrom+0x108/0x1c0
  [<900000000481e27c>] sys_recvfrom+0x1c/0x40
  [<9000000004c076ec>] do_syscall+0x8c/0xc0
  [<9000000003731da4>] handle_syscall+0xc4/0x160
  Code: ...
  ---[ end trace 0000000000000000 ]---
  Kernel panic - not syncing: Fatal exception
  Kernel relocated by 0x3510000
   .text @ 0x9000000003710000
   .data @ 0x9000000004d70000
   .bss  @ 0x9000000006469400
  ---[ end Kernel panic - not syncing: Fatal exception ]---
  [...]

This crash happens every time when running sockmap_skb_verdict_shutdown
subtest in sockmap_basic.

This crash is because a NULL pointer is passed to page_address() in the
sk_msg_recvmsg(). Due to the different implementations depending on the
architecture, page_address(NULL) will trigger a panic on Loongarch
platform but not on x86 platform. So this bug was hidden on x86 platform
for a while, but now it is exposed on Loongarch platform. The root cause
is that a zero length skb (skb->len == 0) was put on the queue.

This zero length skb is a TCP FIN packet, which was sent by shutdown(),
invoked in test_sockmap_skb_verdict_shutdown():

	shutdown(p1, SHUT_WR);

In this case, in sk_psock_skb_ingress_enqueue(), num_sge is zero, and no
page is put to this sge (see sg_set_page in sg_set_page), but this empty
sge is queued into ingress_msg list.

And in sk_msg_recvmsg(), this empty sge is used, and a NULL page is got by
sg_page(sge). Pass this NULL page to copy_page_to_iter(), which passes it
to kmap_local_page() and to page_address(), then kernel panics.

To solve this, we should skip this zero length skb. So in sk_msg_recvmsg(),
if copy is zero, that means it's a zero length skb, skip invoking
copy_page_to_iter(). We are using the EFAULT return triggered by
copy_page_to_iter to check for is_fin in tcp_bpf.c.

Fixes: 604326b ("bpf, sockmap: convert to generic sk_msg interface")
Suggested-by: John Fastabend <[email protected]>
Signed-off-by: Geliang Tang <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Reviewed-by: John Fastabend <[email protected]>
Link: https://lore.kernel.org/bpf/e3a16eacdc6740658ee02a33489b1b9d4912f378.1719992715.git.tanggeliang@kylinos.cn
avpatel pushed a commit that referenced this issue Oct 28, 2024
During the migration of Soundwire runtime stream allocation from
the Qualcomm Soundwire controller to SoC's soundcard drivers the sdm845
soundcard was forgotten.

At this point any playback attempt or audio daemon startup, for instance
on sdm845-db845c (Qualcomm RB3 board), will result in stream pointer
NULL dereference:

 Unable to handle kernel NULL pointer dereference at virtual
 address 0000000000000020
 Mem abort info:
   ESR = 0x0000000096000004
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x04: level 0 translation fault
 Data abort info:
   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 user pgtable: 4k pages, 48-bit VAs, pgdp=0000000101ecf000
 [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
 Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
 Modules linked in: ...
 CPU: 5 UID: 0 PID: 1198 Comm: aplay
 Not tainted 6.12.0-rc2-qcomlt-arm64-00059-g9d78f315a362-dirty #18
 Hardware name: Thundercomm Dragonboard 845c (DT)
 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
 lr : sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
 sp : ffff80008a2035c0
 x29: ffff80008a2035c0 x28: ffff80008a203978 x27: 0000000000000000
 x26: 00000000000000c0 x25: 0000000000000000 x24: ffff1676025f4800
 x23: ffff167600ff1cb8 x22: ffff167600ff1c98 x21: 0000000000000003
 x20: ffff167607316000 x19: ffff167604e64e80 x18: 0000000000000000
 x17: 0000000000000000 x16: ffffcec265074160 x15: 0000000000000000
 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
 x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff167600ff1cec
 x5 : ffffcec22cfa2010 x4 : 0000000000000000 x3 : 0000000000000003
 x2 : ffff167613f836c0 x1 : 0000000000000000 x0 : ffff16761feb60b8
 Call trace:
  sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
  wsa881x_hw_params+0x68/0x80 [snd_soc_wsa881x]
  snd_soc_dai_hw_params+0x3c/0xa4
  __soc_pcm_hw_params+0x230/0x660
  dpcm_be_dai_hw_params+0x1d0/0x3f8
  dpcm_fe_dai_hw_params+0x98/0x268
  snd_pcm_hw_params+0x124/0x460
  snd_pcm_common_ioctl+0x998/0x16e8
  snd_pcm_ioctl+0x34/0x58
  __arm64_sys_ioctl+0xac/0xf8
  invoke_syscall+0x48/0x104
  el0_svc_common.constprop.0+0x40/0xe0
  do_el0_svc+0x1c/0x28
  el0_svc+0x34/0xe0
  el0t_64_sync_handler+0x120/0x12c
  el0t_64_sync+0x190/0x194
 Code: aa0403fb f9418400 9100e000 9400102f (f8420f22)
 ---[ end trace 0000000000000000 ]---

0000000000006108 <sdw_stream_add_slave>:
    6108:       d503233f        paciasp
    610c:       a9b97bfd        stp     x29, x30, [sp, #-112]!
    6110:       910003fd        mov     x29, sp
    6114:       a90153f3        stp     x19, x20, [sp, #16]
    6118:       a9025bf5        stp     x21, x22, [sp, #32]
    611c:       aa0103f6        mov     x22, x1
    6120:       2a0303f5        mov     w21, w3
    6124:       a90363f7        stp     x23, x24, [sp, #48]
    6128:       aa0003f8        mov     x24, x0
    612c:       aa0203f7        mov     x23, x2
    6130:       a9046bf9        stp     x25, x26, [sp, #64]
    6134:       aa0403f9        mov     x25, x4        <-- x4 copied to x25
    6138:       a90573fb        stp     x27, x28, [sp, #80]
    613c:       aa0403fb        mov     x27, x4
    6140:       f9418400        ldr     x0, [x0, #776]
    6144:       9100e000        add     x0, x0, #0x38
    6148:       94000000        bl      0 <mutex_lock>
    614c:       f8420f22        ldr     x2, [x25, #32]!  <-- offset 0x44
    ^^^
This is 0x6108 + offset 0x44 from the beginning of sdw_stream_add_slave()
where data abort happens.
wsa881x_hw_params() is called with stream = NULL and passes it further
in register x4 (5th argument) to sdw_stream_add_slave() without any checks.
Value from x4 is copied to x25 and finally it aborts on trying to load
a value from address in x25 plus offset 32 (in dec) which corresponds
to master_list member in struct sdw_stream_runtime:

struct sdw_stream_runtime {
        const char  *              name;	/*     0     8 */
        struct sdw_stream_params   params;	/*     8    12 */
        enum sdw_stream_state      state;	/*    20     4 */
        enum sdw_stream_type       type;	/*    24     4 */
        /* XXX 4 bytes hole, try to pack */
 here-> struct list_head           master_list;	/*    32    16 */
        int                        m_rt_count;	/*    48     4 */
        /* size: 56, cachelines: 1, members: 6 */
        /* sum members: 48, holes: 1, sum holes: 4 */
        /* padding: 4 */
        /* last cacheline: 56 bytes */

Fix this by adding required calls to qcom_snd_sdw_startup() and
sdw_release_stream() to startup and shutdown routines which restores
the previous correct behaviour when ->set_stream() method is called to
set a valid stream runtime pointer on playback startup.

Reproduced and then fix was tested on db845c RB3 board.

Reported-by: Dmitry Baryshkov <[email protected]>
Cc: [email protected]
Fixes: 15c7fab ("ASoC: qcom: Move Soundwire runtime stream alloc to soundcards")
Cc: Srinivas Kandagatla <[email protected]>
Cc: Dmitry Baryshkov <[email protected]>
Cc: Krzysztof Kozlowski <[email protected]>
Cc: Pierre-Louis Bossart <[email protected]>
Signed-off-by: Alexey Klimov <[email protected]>
Tested-by: Steev Klimaszewski <[email protected]> # Lenovo Yoga C630
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Srinivas Kandagatla <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>
avpatel pushed a commit that referenced this issue Oct 28, 2024
Uprobe needs to fetch args into a percpu buffer, and then copy to ring
buffer to avoid non-atomic context problem.

Sometimes user-space strings, arrays can be very large, but the size of
percpu buffer is only page size. And store_trace_args() won't check
whether these data exceeds a single page or not, caused out-of-bounds
memory access.

It could be reproduced by following steps:
1. build kernel with CONFIG_KASAN enabled
2. save follow program as test.c

```
\#include <stdio.h>
\#include <stdlib.h>
\#include <string.h>

// If string length large than MAX_STRING_SIZE, the fetch_store_strlen()
// will return 0, cause __get_data_size() return shorter size, and
// store_trace_args() will not trigger out-of-bounds access.
// So make string length less than 4096.
\#define STRLEN 4093

void generate_string(char *str, int n)
{
    int i;
    for (i = 0; i < n; ++i)
    {
        char c = i % 26 + 'a';
        str[i] = c;
    }
    str[n-1] = '\0';
}

void print_string(char *str)
{
    printf("%s\n", str);
}

int main()
{
    char tmp[STRLEN];

    generate_string(tmp, STRLEN);
    print_string(tmp);

    return 0;
}
```
3. compile program
`gcc -o test test.c`

4. get the offset of `print_string()`
```
objdump -t test | grep -w print_string
0000000000401199 g     F .text  000000000000001b              print_string
```

5. configure uprobe with offset 0x1199
```
off=0x1199

cd /sys/kernel/debug/tracing/
echo "p /root/test:${off} arg1=+0(%di):ustring arg2=\$comm arg3=+0(%di):ustring"
 > uprobe_events
echo 1 > events/uprobes/enable
echo 1 > tracing_on
```

6. run `test`, and kasan will report error.
==================================================================
BUG: KASAN: use-after-free in strncpy_from_user+0x1d6/0x1f0
Write of size 8 at addr ffff88812311c004 by task test/499CPU: 0 UID: 0 PID: 499 Comm: test Not tainted 6.12.0-rc3+ #18
Hardware name: Red Hat KVM, BIOS 1.16.0-4.al8 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x55/0x70
 print_address_description.constprop.0+0x27/0x310
 kasan_report+0x10f/0x120
 ? strncpy_from_user+0x1d6/0x1f0
 strncpy_from_user+0x1d6/0x1f0
 ? rmqueue.constprop.0+0x70d/0x2ad0
 process_fetch_insn+0xb26/0x1470
 ? __pfx_process_fetch_insn+0x10/0x10
 ? _raw_spin_lock+0x85/0xe0
 ? __pfx__raw_spin_lock+0x10/0x10
 ? __pte_offset_map+0x1f/0x2d0
 ? unwind_next_frame+0xc5f/0x1f80
 ? arch_stack_walk+0x68/0xf0
 ? is_bpf_text_address+0x23/0x30
 ? kernel_text_address.part.0+0xbb/0xd0
 ? __kernel_text_address+0x66/0xb0
 ? unwind_get_return_address+0x5e/0xa0
 ? __pfx_stack_trace_consume_entry+0x10/0x10
 ? arch_stack_walk+0xa2/0xf0
 ? _raw_spin_lock_irqsave+0x8b/0xf0
 ? __pfx__raw_spin_lock_irqsave+0x10/0x10
 ? depot_alloc_stack+0x4c/0x1f0
 ? _raw_spin_unlock_irqrestore+0xe/0x30
 ? stack_depot_save_flags+0x35d/0x4f0
 ? kasan_save_stack+0x34/0x50
 ? kasan_save_stack+0x24/0x50
 ? mutex_lock+0x91/0xe0
 ? __pfx_mutex_lock+0x10/0x10
 prepare_uprobe_buffer.part.0+0x2cd/0x500
 uprobe_dispatcher+0x2c3/0x6a0
 ? __pfx_uprobe_dispatcher+0x10/0x10
 ? __kasan_slab_alloc+0x4d/0x90
 handler_chain+0xdd/0x3e0
 handle_swbp+0x26e/0x3d0
 ? __pfx_handle_swbp+0x10/0x10
 ? uprobe_pre_sstep_notifier+0x151/0x1b0
 irqentry_exit_to_user_mode+0xe2/0x1b0
 asm_exc_int3+0x39/0x40
RIP: 0033:0x401199
Code: 01 c2 0f b6 45 fb 88 02 83 45 fc 01 8b 45 fc 3b 45 e4 7c b7 8b 45 e4 48 98 48 8d 50 ff 48 8b 45 e8 48 01 d0 ce
RSP: 002b:00007ffdf00576a8 EFLAGS: 00000206
RAX: 00007ffdf00576b0 RBX: 0000000000000000 RCX: 0000000000000ff2
RDX: 0000000000000ffc RSI: 0000000000000ffd RDI: 00007ffdf00576b0
RBP: 00007ffdf00586b0 R08: 00007feb2f9c0d20 R09: 00007feb2f9c0d20
R10: 0000000000000001 R11: 0000000000000202 R12: 0000000000401040
R13: 00007ffdf0058780 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

This commit enforces the buffer's maxlen less than a page-size to avoid
store_trace_args() out-of-memory access.

Link: https://lore.kernel.org/all/[email protected]/

Fixes: dcad1a2 ("tracing/uprobes: Fetch args before reserving a ring buffer")
Signed-off-by: Qiao Ma <[email protected]>
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
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