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没有kernel的配置文件 #1

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zx121122 opened this issue May 12, 2015 · 3 comments
Closed

没有kernel的配置文件 #1

zx121122 opened this issue May 12, 2015 · 3 comments
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@zx121122
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没有kernel的配置文件。不知道编译kernel时使用什么配置文件,难道是msm8960-perf_defconfig或msm9615_defconfig?

@M1cha
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M1cha commented May 12, 2015

atm this repository is a pure CAF kernel without support for aries.
It will take some time for Ivan to add support for it because he started from scratch to make it more stable.

@M1cha M1cha added the question label May 12, 2015
ivan19871002 pushed a commit that referenced this issue May 12, 2015
commit 086ba77a6db00ed858ff07451bedee197df868c9 upstream.

ARM has some private syscalls (for example, set_tls(2)) which lie
outside the range of NR_syscalls.  If any of these are called while
syscall tracing is being performed, out-of-bounds array access will
occur in the ftrace and perf sys_{enter,exit} handlers.

 # trace-cmd record -e raw_syscalls:* true && trace-cmd report
 ...
 true-653   [000]   384.675777: sys_enter:            NR 192 (0, 1000, 3, 4000022, ffffffff, 0)
 true-653   [000]   384.675812: sys_exit:             NR 192 = 1995915264
 true-653   [000]   384.675971: sys_enter:            NR 983045 (76f74480, 76f74000, 76f74b28, 76f74480, 76f76f74, 1)
 true-653   [000]   384.675988: sys_exit:             NR 983045 = 0
 ...

 # trace-cmd record -e syscalls:* true
 [   17.289329] Unable to handle kernel paging request at virtual address aaaaaace
 [   17.289590] pgd = 9e71c000
 [   17.289696] [aaaaaace] *pgd=00000000
 [   17.289985] Internal error: Oops: 5 [#1] PREEMPT SMP ARM
 [   17.290169] Modules linked in:
 [   17.290391] CPU: 0 PID: 704 Comm: true Not tainted 3.18.0-rc2+ #21
 [   17.290585] task: 9f4dab00 ti: 9e710000 task.ti: 9e710000
 [   17.290747] PC is at ftrace_syscall_enter+0x48/0x1f8
 [   17.290866] LR is at syscall_trace_enter+0x124/0x184

Fix this by ignoring out-of-NR_syscalls-bounds syscall numbers.

Commit cd0980f "tracing: Check invalid syscall nr while tracing syscalls"
added the check for less than zero, but it should have also checked
for greater than NR_syscalls.

Link: http://lkml.kernel.org/p/1414620418-29472-1-git-send-email-rabin@rab.in

Fixes: cd0980f "tracing: Check invalid syscall nr while tracing syscalls"
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li <lizefan@huawei.com>
ivan19871002 pushed a commit that referenced this issue May 12, 2015
commit 42d64e1add3a1ce8a787116036163b8724362145 upstream.

The SELinux/NetLabel glue code has a locking bug that affects systems
with NetLabel enabled, see the kernel error message below.  This patch
corrects this problem by converting the bottom half socket lock to a
more conventional, and correct for this call-path, lock_sock() call.

 ===============================
 [ INFO: suspicious RCU usage. ]
 3.11.0-rc3+ #19 Not tainted
 -------------------------------
 net/ipv4/cipso_ipv4.c:1928 suspicious rcu_dereference_protected() usage!

 other info that might help us debug this:

 rcu_scheduler_active = 1, debug_locks = 0
 2 locks held by ping/731:
  #0:  (slock-AF_INET/1){+.-...}, at: [...] selinux_netlbl_socket_connect
  #1:  (rcu_read_lock){.+.+..}, at: [<...>] netlbl_conn_setattr

 stack backtrace:
 CPU: 1 PID: 731 Comm: ping Not tainted 3.11.0-rc3+ #19
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  0000000000000001 ffff88006f659d28 ffffffff81726b6a ffff88003732c500
  ffff88006f659d58 ffffffff810e4457 ffff88006b845a00 0000000000000000
  000000000000000c ffff880075aa2f50 ffff88006f659d90 ffffffff8169bec7
 Call Trace:
  [<ffffffff81726b6a>] dump_stack+0x54/0x74
  [<ffffffff810e4457>] lockdep_rcu_suspicious+0xe7/0x120
  [<ffffffff8169bec7>] cipso_v4_sock_setattr+0x187/0x1a0
  [<ffffffff8170f317>] netlbl_conn_setattr+0x187/0x190
  [<ffffffff8170f195>] ? netlbl_conn_setattr+0x5/0x190
  [<ffffffff8131ac9e>] selinux_netlbl_socket_connect+0xae/0xc0
  [<ffffffff81303025>] selinux_socket_connect+0x135/0x170
  [<ffffffff8119d127>] ? might_fault+0x57/0xb0
  [<ffffffff812fb146>] security_socket_connect+0x16/0x20
  [<ffffffff815d3ad3>] SYSC_connect+0x73/0x130
  [<ffffffff81739a85>] ? sysret_check+0x22/0x5d
  [<ffffffff810e5e2d>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff81373d4e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
  [<ffffffff815d52be>] SyS_connect+0xe/0x10
  [<ffffffff81739a59>] system_call_fastpath+0x16/0x1b

Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ivan19871002 pushed a commit that referenced this issue May 12, 2015
…ernor

For the sync_freq feature currently we check pcpu->policy->cur frequency
for each online cpu.  But for a CPU that isn't using interactive governor
or for an offline CPU, pcpu->policy can be null or an invalid value.
This patch tries to avoid that scenario by using pcpu->target_freq
instead of policy->cur to get the frequency of an online CPU.

Kernel crash without this patch:
[   20.132373] Unable to handle kernel NULL pointer dereference at virtual address 00000028
[   20.132375] pgd = c34f34c0
[   20.132377] pgd = ef6f2440
[   20.132383] [00000028] *pgd=00000000
[   20.132385]
[   20.132388] [00000028] *pgd=2e98f003, *pmd=00000000
[   20.132390] Internal error: Oops: 205 [#1] PREEMPT SMP ARM
[   20.132394] Modules linked in:
[   20.132398] CPU: 0 PID: 1560 Comm: chown Tainted: G        W    3.10.0-perf-gb12057b-00001-ga2c6c16-dirty MiCode#7
[   20.132401] task: ef9af300 ti: ee49c000 task.ti: ee49c000
[   20.132411] PC is at cpufreq_interactive_timer+0x10c/0x650
[   20.132415] LR is at cpufreq_interactive_timer+0x128/0x650
<snip>
[   20.133002] [<c07eb204>] (cpufreq_interactive_timer+0x10c/0x650) from [<c02804d8>] (call_timer_fn+0x80/0x198)
[   20.133012] [<c02804d8>] (call_timer_fn+0x80/0x198) from [<c0280acc>] (run_timer_softirq+0x1f8/0x270)
[   20.133019] [<c0280acc>] (run_timer_softirq+0x1f8/0x270) from [<c0279e20>] (__do_softirq+0x12c/0x2d4)
[   20.133025] [<c0279e20>] (__do_softirq+0x12c/0x2d4) from [<c027a2d4>] (irq_exit+0x74/0xc8)
[   20.133034] [<c027a2d4>] (irq_exit+0x74/0xc8) from [<c0206a00>] (handle_IRQ+0x68/0x8c)
[   20.133041] [<c0206a00>] (handle_IRQ+0x68/0x8c) from [<c02004b8>] (gic_handle_irq+0x3c/0x60)
[   20.133051] [<c02004b8>] (gic_handle_irq+0x3c/0x60) from [<c0ac6900>] (__irq_svc+0x40/0x70)
<snip>

Change-Id: I4adf0b35cd94004e06ea649c672988db45c54710
Signed-off-by: Vijay Ganti <viganti@codeaurora.org>
@zx121122
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thanks for your answer

@M1cha
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M1cha commented May 12, 2015

it has been updated now :)

M1cha pushed a commit that referenced this issue Jul 27, 2015
commit 6d1cff2a885850b78b40c34777b46cf5da5d1050 upstream.

We hit use after free on dereferncing pointer to task_smack struct in
smk_of_task() called from smack_task_to_inode().

task_security() macro uses task_cred_xxx() to get pointer to the task_smack.
task_cred_xxx() could be used only for non-pointer members of task's
credentials. It cannot be used for pointer members since what they point
to may disapper after dropping RCU read lock.

Mainly task_security() used this way:
	smk_of_task(task_security(p))

Intead of this introduce function smk_of_task_struct() which
takes task_struct as argument and returns pointer to smk_known struct
and do this under RCU read lock.
Bogus task_security() macro is not used anymore, so remove it.

KASan's report for this:

	AddressSanitizer: use after free in smack_task_to_inode+0x50/0x70 at addr c4635600
	=============================================================================
	BUG kmalloc-64 (Tainted: PO): kasan error
	-----------------------------------------------------------------------------

	Disabling lock debugging due to kernel taint
	INFO: Allocated in new_task_smack+0x44/0xd8 age=39 cpu=0 pid=1866
		kmem_cache_alloc_trace+0x88/0x1bc
		new_task_smack+0x44/0xd8
		smack_cred_prepare+0x48/0x21c
		security_prepare_creds+0x44/0x4c
		prepare_creds+0xdc/0x110
		smack_setprocattr+0x104/0x150
		security_setprocattr+0x4c/0x54
		proc_pid_attr_write+0x12c/0x194
		vfs_write+0x1b0/0x370
		SyS_write+0x5c/0x94
		ret_fast_syscall+0x0/0x48
	INFO: Freed in smack_cred_free+0xc4/0xd0 age=27 cpu=0 pid=1564
		kfree+0x270/0x290
		smack_cred_free+0xc4/0xd0
		security_cred_free+0x34/0x3c
		put_cred_rcu+0x58/0xcc
		rcu_process_callbacks+0x738/0x998
		__do_softirq+0x264/0x4cc
		do_softirq+0x94/0xf4
		irq_exit+0xbc/0x120
		handle_IRQ+0x104/0x134
		gic_handle_irq+0x70/0xac
		__irq_svc+0x44/0x78
		_raw_spin_unlock+0x18/0x48
		sync_inodes_sb+0x17c/0x1d8
		sync_filesystem+0xac/0xfc
		vdfs_file_fsync+0x90/0xc0
		vfs_fsync_range+0x74/0x7c
	INFO: Slab 0xd3b23f50 objects=32 used=31 fp=0xc4635600 flags=0x4080
	INFO: Object 0xc4635600 @offset=5632 fp=0x  (null)

	Bytes b4 c46355f0: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a  ZZZZZZZZZZZZZZZZ
	Object c4635600: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
	Object c4635610: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
	Object c4635620: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
	Object c4635630: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5  kkkkkkkkkkkkkkk.
	Redzone c4635640: bb bb bb bb                                      ....
	Padding c46356e8: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a  ZZZZZZZZZZZZZZZZ
	Padding c46356f8: 5a 5a 5a 5a 5a 5a 5a 5a                          ZZZZZZZZ
	CPU: 5 PID: 834 Comm: launchpad_prelo Tainted: PBO 3.10.30 #1
	Backtrace:
	[<c00233a4>] (dump_backtrace+0x0/0x158) from [<c0023dec>] (show_stack+0x20/0x24)
	 r7:c4634010 r6:d3b23f50 r5:c4635600 r4:d1002140
	[<c0023dcc>] (show_stack+0x0/0x24) from [<c06d6d7c>] (dump_stack+0x20/0x28)
	[<c06d6d5c>] (dump_stack+0x0/0x28) from [<c01c1d50>] (print_trailer+0x124/0x144)
	[<c01c1c2c>] (print_trailer+0x0/0x144) from [<c01c1e88>] (object_err+0x3c/0x44)
	 r7:c4635600 r6:d1002140 r5:d3b23f50 r4:c4635600
	[<c01c1e4c>] (object_err+0x0/0x44) from [<c01cac18>] (kasan_report_error+0x2b8/0x538)
	 r6:d1002140 r5:d3b23f50 r4:c6429cf8 r3:c09e1aa7
	[<c01ca960>] (kasan_report_error+0x0/0x538) from [<c01c9430>] (__asan_load4+0xd4/0xf8)
	[<c01c935c>] (__asan_load4+0x0/0xf8) from [<c031e168>] (smack_task_to_inode+0x50/0x70)
	 r5:c4635600 r4:ca9da000
	[<c031e118>] (smack_task_to_inode+0x0/0x70) from [<c031af64>] (security_task_to_inode+0x3c/0x44)
	 r5:cca25e80 r4:c0ba9780
	[<c031af28>] (security_task_to_inode+0x0/0x44) from [<c023d614>] (pid_revalidate+0x124/0x178)
	 r6:00000000 r5:cca25e80 r4:cbabe3c0 r3:00008124
	[<c023d4f0>] (pid_revalidate+0x0/0x178) from [<c01db98c>] (lookup_fast+0x35c/0x43y4)
	 r9:c6429efc r8:00000101 r7:c079d940 r6:c6429e90 r5:c6429ed8 r4:c83c4148
	[<c01db630>] (lookup_fast+0x0/0x434) from [<c01deec8>] (do_last.isra.24+0x1c0/0x1108)
	[<c01ded08>] (do_last.isra.24+0x0/0x1108) from [<c01dff04>] (path_openat.isra.25+0xf4/0x648)
	[<c01dfe10>] (path_openat.isra.25+0x0/0x648) from [<c01e1458>] (do_filp_open+0x3c/0x88)
	[<c01e141c>] (do_filp_open+0x0/0x88) from [<c01ccb28>] (do_sys_open+0xf0/0x198)
	 r7:00000001 r6:c0ea2180 r5:0000000b r4:00000000
	[<c01cca38>] (do_sys_open+0x0/0x198) from [<c01ccc00>] (SyS_open+0x30/0x34)
	[<c01ccbd0>] (SyS_open+0x0/0x34) from [<c001db80>] (ret_fast_syscall+0x0/0x48)
	Read of size 4 by thread T834:
	Memory state around the buggy address:
	 c4635380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
	 c4635400: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
	 c4635480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
	 c4635500: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
	 c4635580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
	>c4635600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
	           ^
	 c4635680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
	 c4635700: 00 00 00 00 04 fc fc fc fc fc fc fc fc fc fc fc
	 c4635780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
	 c4635800: 00 00 00 00 00 00 04 fc fc fc fc fc fc fc fc fc
	 c4635880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
	==================================================================

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
[lizf: Backported to 3.4:
 - smk_of_task() returns char* instead of smack_known *
 - replace task_security() with smk_of_task() with smk_of_task_struct()
   manually]
Signed-off-by: Zefan Li <lizefan@huawei.com>
M1cha pushed a commit that referenced this issue Jul 27, 2015
commit a28b2a47edcd0cb7c051b445f71a426000394606 upstream.

Passing zeroed drm_radeon_cs struct to DRM_IOCTL_RADEON_CS produces the
following oops.

Fix by always calling INIT_LIST_HEAD() to avoid the crash in list_sort().

----------------------------------

 #include <stdint.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <sys/ioctl.h>
 #include <drm/radeon_drm.h>

 static const struct drm_radeon_cs cs;

 int main(int argc, char **argv)
 {
         return ioctl(open(argv[1], O_RDWR), DRM_IOCTL_RADEON_CS, &cs);
 }

----------------------------------

[ttrantal@test2 ~]$ ./main /dev/dri/card0
[   46.904650] BUG: unable to handle kernel NULL pointer dereference at           (null)
[   46.905022] IP: [<ffffffff814d6df2>] list_sort+0x42/0x240
[   46.905022] PGD 68f29067 PUD 688b5067 PMD 0
[   46.905022] Oops: 0002 [#1] SMP
[   46.905022] CPU: 0 PID: 2413 Comm: main Not tainted 4.0.0-rc1+ #58
[   46.905022] Hardware name: Hewlett-Packard HP Compaq dc5750 Small Form Factor/0A64h, BIOS 786E3 v02.10 01/25/2007
[   46.905022] task: ffff880058e2bcc0 ti: ffff880058e64000 task.ti: ffff880058e64000
[   46.905022] RIP: 0010:[<ffffffff814d6df2>]  [<ffffffff814d6df2>] list_sort+0x42/0x240
[   46.905022] RSP: 0018:ffff880058e67998  EFLAGS: 00010246
[   46.905022] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   46.905022] RDX: ffffffff81644410 RSI: ffff880058e67b40 RDI: ffff880058e67a58
[   46.905022] RBP: ffff880058e67a88 R08: 0000000000000000 R09: 0000000000000000
[   46.905022] R10: ffff880058e2bcc0 R11: ffffffff828e6ca0 R12: ffffffff81644410
[   46.905022] R13: ffff8800694b8018 R14: 0000000000000000 R15: ffff880058e679b0
[   46.905022] FS:  00007fdc65a65700(0000) GS:ffff88006d600000(0000) knlGS:0000000000000000
[   46.905022] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   46.905022] CR2: 0000000000000000 CR3: 0000000058dd9000 CR4: 00000000000006f0
[   46.905022] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   46.905022] DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
[   46.905022] Stack:
[   46.905022]  ffff880058e67b40 ffff880058e2bcc0 ffff880058e67a78 0000000000000000
[   46.905022]  0000000000000000 0000000000000000 0000000000000000 0000000000000000
[   46.905022]  0000000000000000 0000000000000000 0000000000000000 0000000000000000
[   46.905022] Call Trace:
[   46.905022]  [<ffffffff81644a65>] radeon_cs_parser_fini+0x195/0x220
[   46.905022]  [<ffffffff81645069>] radeon_cs_ioctl+0xa9/0x960
[   46.905022]  [<ffffffff815e1f7c>] drm_ioctl+0x19c/0x640
[   46.905022]  [<ffffffff810f8fdd>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[   46.905022]  [<ffffffff810f90ad>] ? trace_hardirqs_on+0xd/0x10
[   46.905022]  [<ffffffff8160c066>] radeon_drm_ioctl+0x46/0x80
[   46.905022]  [<ffffffff81211868>] do_vfs_ioctl+0x318/0x570
[   46.905022]  [<ffffffff81462ef6>] ? selinux_file_ioctl+0x56/0x110
[   46.905022]  [<ffffffff81211b41>] SyS_ioctl+0x81/0xa0
[   46.905022]  [<ffffffff81dc6312>] system_call_fastpath+0x12/0x17
[   46.905022] Code: 48 89 b5 10 ff ff ff 0f 84 03 01 00 00 4c 8d bd 28 ff ff
ff 31 c0 48 89 fb b9 15 00 00 00 49 89 d4 4c 89 ff f3 48 ab 48 8b 46 08 <48> c7
00 00 00 00 00 48 8b 0e 48 85 c9 0f 84 7d 00 00 00 c7 85
[   46.905022] RIP  [<ffffffff814d6df2>] list_sort+0x42/0x240
[   46.905022]  RSP <ffff880058e67998>
[   46.905022] CR2: 0000000000000000
[   47.149253] ---[ end trace 09576b4e8b2c20b8 ]---

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Tommi Rantala <tt.rantala@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
M1cha pushed a commit that referenced this issue Jul 27, 2015
commit 6302ce4d80aa82b3fdb5c5cd68e7268037091b47 upstream.

This crash was reported:

[  366.947370] sd 3:0:1:0: [sdb] Spinning up disk....
[  368.804046] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  368.804072] IP: [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[  368.804098] PGD 0
[  368.804114] Oops: 0002 [#1] SMP
[  368.804143] CPU 1
[  368.804151] Modules linked in: sg netconsole s3g(PO) uinput joydev hid_multitouch usbhid hid snd_hda_codec_via cpufreq_userspace cpufreq_powersave cpufreq_stats uhci_hcd cpufreq_conservative snd_hda_intel snd_hda_codec snd_hwdep snd_pcm sdhci_pci snd_page_alloc sdhci snd_timer snd psmouse evdev serio_raw pcspkr soundcore xhci_hcd shpchp s3g_drm(O) mvsas mmc_core ahci libahci drm i2c_core acpi_cpufreq mperf video processor button thermal_sys dm_dmirror exfat_fs exfat_core dm_zcache dm_mod padlock_aes aes_generic padlock_sha iscsi_target_mod target_core_mod configfs sswipe libsas libata scsi_transport_sas picdev via_cputemp hwmon_vid fuse parport_pc ppdev lp parport autofs4 ext4 crc16 mbcache jbd2 sd_mod crc_t10dif usb_storage scsi_mod ehci_hcd usbcore usb_common
[  368.804749]
[  368.804764] Pid: 392, comm: kworker/u:3 Tainted: P        W  O 3.4.87-logicube-ng.22 #1 To be filled by O.E.M. To be filled by O.E.M./EPIA-M920
[  368.804802] RIP: 0010:[<ffffffff81358457>]  [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[  368.804827] RSP: 0018:ffff880117001cc0  EFLAGS: 00010246
[  368.804842] RAX: 0000000000000000 RBX: ffff8801185030d0 RCX: ffff88008edcb420
[  368.804857] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff8801185030d4
[  368.804873] RBP: ffff8801181531c0 R08: 0000000000000020 R09: 00000000fffffffe
[  368.804885] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801185030d4
[  368.804899] R13: 0000000000000002 R14: ffff880117001fd8 R15: ffff8801185030d8
[  368.804916] FS:  0000000000000000(0000) GS:ffff88011fc80000(0000) knlGS:0000000000000000
[  368.804931] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  368.804946] CR2: 0000000000000000 CR3: 000000000160b000 CR4: 00000000000006e0
[  368.804962] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  368.804978] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  368.804995] Process kworker/u:3 (pid: 392, threadinfo ffff880117000000, task ffff8801181531c0)
[  368.805009] Stack:
[  368.805017]  ffff8801185030d8 0000000000000000 ffffffff8161ddf0 ffffffff81056f7c
[  368.805062]  000000000000b503 ffff8801185030d0 ffff880118503000 0000000000000000
[  368.805100]  ffff8801185030d0 ffff8801188b8000 ffff88008edcb420 ffffffff813583ac
[  368.805135] Call Trace:
[  368.805153]  [<ffffffff81056f7c>] ? up+0xb/0x33
[  368.805168]  [<ffffffff813583ac>] ? mutex_lock+0x16/0x25
[  368.805194]  [<ffffffffa018c414>] ? smp_execute_task+0x4e/0x222 [libsas]
[  368.805217]  [<ffffffffa018ce1c>] ? sas_find_bcast_dev+0x3c/0x15d [libsas]
[  368.805240]  [<ffffffffa018ce4f>] ? sas_find_bcast_dev+0x6f/0x15d [libsas]
[  368.805264]  [<ffffffffa018e989>] ? sas_ex_revalidate_domain+0x37/0x2ec [libsas]
[  368.805280]  [<ffffffff81355a2a>] ? printk+0x43/0x48
[  368.805296]  [<ffffffff81359a65>] ? _raw_spin_unlock_irqrestore+0xc/0xd
[  368.805318]  [<ffffffffa018b767>] ? sas_revalidate_domain+0x85/0xb6 [libsas]
[  368.805336]  [<ffffffff8104e5d9>] ? process_one_work+0x151/0x27c
[  368.805351]  [<ffffffff8104f6cd>] ? worker_thread+0xbb/0x152
[  368.805366]  [<ffffffff8104f612>] ? manage_workers.isra.29+0x163/0x163
[  368.805382]  [<ffffffff81052c4e>] ? kthread+0x79/0x81
[  368.805399]  [<ffffffff8135fea4>] ? kernel_thread_helper+0x4/0x10
[  368.805416]  [<ffffffff81052bd5>] ? kthread_flush_work_fn+0x9/0x9
[  368.805431]  [<ffffffff8135fea0>] ? gs_change+0x13/0x13
[  368.805442] Code: 83 7d 30 63 7e 04 f3 90 eb ab 4c 8d 63 04 4c 8d 7b 08 4c 89 e7 e8 fa 15 00 00 48 8b 43 10 4c 89 3c 24 48 89 63 10 48 89 44 24 08 <48> 89 20 83 c8 ff 48 89 6c 24 10 87 03 ff c8 74 35 4d 89 ee 41
[  368.805851] RIP  [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[  368.805877]  RSP <ffff880117001cc0>
[  368.805886] CR2: 0000000000000000
[  368.805899] ---[ end trace b720682065d8f4cc ]---

It's directly caused by 89d3cf6 [SCSI] libsas: add mutex for SMP task
execution, but shows a deeper cause: expander functions expect to be able to
cast to and treat domain devices as expanders.  The correct fix is to only do
expander discover when we know we've got an expander device to avoid wrongly
casting a non-expander device.

Reported-by: Praveen Murali <pmurali@logicube.com>
Tested-by: Praveen Murali <pmurali@logicube.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
M1cha pushed a commit that referenced this issue Jul 27, 2015
…ernor

For the sync_freq feature currently we check pcpu->policy->cur frequency
for each online cpu.  But for a CPU that isn't using interactive governor
or for an offline CPU, pcpu->policy can be null or an invalid value.
This patch tries to avoid that scenario by using pcpu->target_freq
instead of policy->cur to get the frequency of an online CPU.

Kernel crash without this patch:
[   20.132373] Unable to handle kernel NULL pointer dereference at virtual address 00000028
[   20.132375] pgd = c34f34c0
[   20.132377] pgd = ef6f2440
[   20.132383] [00000028] *pgd=00000000
[   20.132385]
[   20.132388] [00000028] *pgd=2e98f003, *pmd=00000000
[   20.132390] Internal error: Oops: 205 [#1] PREEMPT SMP ARM
[   20.132394] Modules linked in:
[   20.132398] CPU: 0 PID: 1560 Comm: chown Tainted: G        W    3.10.0-perf-gb12057b-00001-ga2c6c16-dirty MiCode#7
[   20.132401] task: ef9af300 ti: ee49c000 task.ti: ee49c000
[   20.132411] PC is at cpufreq_interactive_timer+0x10c/0x650
[   20.132415] LR is at cpufreq_interactive_timer+0x128/0x650
<snip>
[   20.133002] [<c07eb204>] (cpufreq_interactive_timer+0x10c/0x650) from [<c02804d8>] (call_timer_fn+0x80/0x198)
[   20.133012] [<c02804d8>] (call_timer_fn+0x80/0x198) from [<c0280acc>] (run_timer_softirq+0x1f8/0x270)
[   20.133019] [<c0280acc>] (run_timer_softirq+0x1f8/0x270) from [<c0279e20>] (__do_softirq+0x12c/0x2d4)
[   20.133025] [<c0279e20>] (__do_softirq+0x12c/0x2d4) from [<c027a2d4>] (irq_exit+0x74/0xc8)
[   20.133034] [<c027a2d4>] (irq_exit+0x74/0xc8) from [<c0206a00>] (handle_IRQ+0x68/0x8c)
[   20.133041] [<c0206a00>] (handle_IRQ+0x68/0x8c) from [<c02004b8>] (gic_handle_irq+0x3c/0x60)
[   20.133051] [<c02004b8>] (gic_handle_irq+0x3c/0x60) from [<c0ac6900>] (__irq_svc+0x40/0x70)
<snip>

Change-Id: I4adf0b35cd94004e06ea649c672988db45c54710
Signed-off-by: Vijay Ganti <viganti@codeaurora.org>
ivan19871002 pushed a commit that referenced this issue Nov 26, 2015
commit ce7514526742c0898b837d4395f515b79dfb5a12 upstream.

It is possible for ata_sff_flush_pio_task() to set ap->hsm_task_state to
HSM_ST_IDLE in between the time __ata_sff_port_intr() checks for HSM_ST_IDLE
and before it calls ata_sff_hsm_move() causing ata_sff_hsm_move() to BUG().

This problem is hard to reproduce making this patch hard to verify, but this
fix will prevent the race.

I have not been able to reproduce the problem, but here is a crash dump from
a 2.6.32 kernel.

On examining the ata port's state, its hsm_task_state field has a value of HSM_ST_IDLE:

crash> struct ata_port.hsm_task_state ffff881c1121c000
  hsm_task_state = 0

Normally, this should not be possible as ata_sff_hsm_move() was called from ata_sff_host_intr(),
which checks hsm_task_state and won't call ata_sff_hsm_move() if it has a HSM_ST_IDLE value.

PID: 11053  TASK: ffff8816e846cae0  CPU: 0   COMMAND: "sshd"
 #0 [ffff88008ba03960] machine_kexec at ffffffff81038f3b
 #1 [ffff88008ba039c0] crash_kexec at ffffffff810c5d92
 #2 [ffff88008ba03a90] oops_end at ffffffff8152b510
 MiCode#3 [ffff88008ba03ac0] die at ffffffff81010e0b
 MiCode#4 [ffff88008ba03af0] do_trap at ffffffff8152ad74
 MiCode#5 [ffff88008ba03b50] do_invalid_op at ffffffff8100cf95
 MiCode#6 [ffff88008ba03bf0] invalid_op at ffffffff8100bf9b
    [exception RIP: ata_sff_hsm_move+317]
    RIP: ffffffff813a77ad  RSP: ffff88008ba03ca0  RFLAGS: 00010097
    RAX: 0000000000000000  RBX: ffff881c1121dc60  RCX: 0000000000000000
    RDX: ffff881c1121dd10  RSI: ffff881c1121dc60  RDI: ffff881c1121c000
    RBP: ffff88008ba03d00   R8: 0000000000000000   R9: 000000000000002e
    R10: 000000000001003f  R11: 000000000000009b  R12: ffff881c1121c000
    R13: 0000000000000000  R14: 0000000000000050  R15: ffff881c1121dd78
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 MiCode#7 [ffff88008ba03d08] ata_sff_host_intr at ffffffff813a7fbd
 MiCode#8 [ffff88008ba03d38] ata_sff_interrupt at ffffffff813a821e
 MiCode#9 [ffff88008ba03d78] handle_IRQ_event at ffffffff810e6ec0
ivan19871002 pushed a commit that referenced this issue Nov 26, 2015
commit 600ddd6825543962fb807884169e57b580dba208 upstream.

When hitting an INIT collision case during the 4WHS with AUTH enabled, as
already described in detail in commit 1be9a950c646 ("net: sctp: inherit
auth_capable on INIT collisions"), it can happen that we occasionally
still remotely trigger the following panic on server side which seems to
have been uncovered after the fix from commit 1be9a950c646 ...

[  533.876389] BUG: unable to handle kernel paging request at 00000000ffffffff
[  533.913657] IP: [<ffffffff811ac385>] __kmalloc+0x95/0x230
[  533.940559] PGD 5030f2067 PUD 0
[  533.957104] Oops: 0000 [#1] SMP
[  533.974283] Modules linked in: sctp mlx4_en [...]
[  534.939704] Call Trace:
[  534.951833]  [<ffffffff81294e30>] ? crypto_init_shash_ops+0x60/0xf0
[  534.984213]  [<ffffffff81294e30>] crypto_init_shash_ops+0x60/0xf0
[  535.015025]  [<ffffffff8128c8ed>] __crypto_alloc_tfm+0x6d/0x170
[  535.045661]  [<ffffffff8128d12c>] crypto_alloc_base+0x4c/0xb0
[  535.074593]  [<ffffffff8160bd42>] ? _raw_spin_lock_bh+0x12/0x50
[  535.105239]  [<ffffffffa0418c11>] sctp_inet_listen+0x161/0x1e0 [sctp]
[  535.138606]  [<ffffffff814e43bd>] SyS_listen+0x9d/0xb0
[  535.166848]  [<ffffffff816149a9>] system_call_fastpath+0x16/0x1b

... or depending on the the application, for example this one:

[ 1370.026490] BUG: unable to handle kernel paging request at 00000000ffffffff
[ 1370.026506] IP: [<ffffffff811ab455>] kmem_cache_alloc+0x75/0x1d0
[ 1370.054568] PGD 633c94067 PUD 0
[ 1370.070446] Oops: 0000 [#1] SMP
[ 1370.085010] Modules linked in: sctp kvm_amd kvm [...]
[ 1370.963431] Call Trace:
[ 1370.974632]  [<ffffffff8120f7cf>] ? SyS_epoll_ctl+0x53f/0x960
[ 1371.000863]  [<ffffffff8120f7cf>] SyS_epoll_ctl+0x53f/0x960
[ 1371.027154]  [<ffffffff812100d3>] ? anon_inode_getfile+0xd3/0x170
[ 1371.054679]  [<ffffffff811e3d67>] ? __alloc_fd+0xa7/0x130
[ 1371.080183]  [<ffffffff816149a9>] system_call_fastpath+0x16/0x1b

With slab debugging enabled, we can see that the poison has been overwritten:

[  669.826368] BUG kmalloc-128 (Tainted: G        W     ): Poison overwritten
[  669.826385] INFO: 0xffff880228b32e50-0xffff880228b32e50. First byte 0x6a instead of 0x6b
[  669.826414] INFO: Allocated in sctp_auth_create_key+0x23/0x50 [sctp] age=3 cpu=0 pid=18494
[  669.826424]  __slab_alloc+0x4bf/0x566
[  669.826433]  __kmalloc+0x280/0x310
[  669.826453]  sctp_auth_create_key+0x23/0x50 [sctp]
[  669.826471]  sctp_auth_asoc_create_secret+0xcb/0x1e0 [sctp]
[  669.826488]  sctp_auth_asoc_init_active_key+0x68/0xa0 [sctp]
[  669.826505]  sctp_do_sm+0x29d/0x17c0 [sctp] [...]
[  669.826629] INFO: Freed in kzfree+0x31/0x40 age=1 cpu=0 pid=18494
[  669.826635]  __slab_free+0x39/0x2a8
[  669.826643]  kfree+0x1d6/0x230
[  669.826650]  kzfree+0x31/0x40
[  669.826666]  sctp_auth_key_put+0x19/0x20 [sctp]
[  669.826681]  sctp_assoc_update+0x1ee/0x2d0 [sctp]
[  669.826695]  sctp_do_sm+0x674/0x17c0 [sctp]

Since this only triggers in some collision-cases with AUTH, the problem at
heart is that sctp_auth_key_put() on asoc->asoc_shared_key is called twice
when having refcnt 1, once directly in sctp_assoc_update() and yet again
from within sctp_auth_asoc_init_active_key() via sctp_assoc_update() on
the already kzfree'd memory, which is also consistent with the observation
of the poison decrease from 0x6b to 0x6a (note: the overwrite is detected
at a later point in time when poison is checked on new allocation).

Reference counting of auth keys revisited:

Shared keys for AUTH chunks are being stored in endpoints and associations
in endpoint_shared_keys list. On endpoint creation, a null key is being
added; on association creation, all endpoint shared keys are being cached
and thus cloned over to the association. struct sctp_shared_key only holds
a pointer to the actual key bytes, that is, struct sctp_auth_bytes which
keeps track of users internally through refcounting. Naturally, on assoc
or enpoint destruction, sctp_shared_key are being destroyed directly and
the reference on sctp_auth_bytes dropped.

User space can add keys to either list via setsockopt(2) through struct
sctp_authkey and by passing that to sctp_auth_set_key() which replaces or
adds a new auth key. There, sctp_auth_create_key() creates a new sctp_auth_bytes
with refcount 1 and in case of replacement drops the reference on the old
sctp_auth_bytes. A key can be set active from user space through setsockopt()
on the id via sctp_auth_set_active_key(), which iterates through either
endpoint_shared_keys and in case of an assoc, invokes (one of various places)
sctp_auth_asoc_init_active_key().

sctp_auth_asoc_init_active_key() computes the actual secret from local's
and peer's random, hmac and shared key parameters and returns a new key
directly as sctp_auth_bytes, that is asoc->asoc_shared_key, plus drops
the reference if there was a previous one. The secret, which where we
eventually double drop the ref comes from sctp_auth_asoc_set_secret() with
intitial refcount of 1, which also stays unchanged eventually in
sctp_assoc_update(). This key is later being used for crypto layer to
set the key for the hash in crypto_hash_setkey() from sctp_auth_calculate_hmac().

To close the loop: asoc->asoc_shared_key is freshly allocated secret
material and independant of the sctp_shared_key management keeping track
of only shared keys in endpoints and assocs. Hence, also commit 4184b2a79a76
("net: sctp: fix memory leak in auth key management") is independant of
this bug here since it concerns a different layer (though same structures
being used eventually). asoc->asoc_shared_key is reference dropped correctly
on assoc destruction in sctp_association_free() and when active keys are
being replaced in sctp_auth_asoc_init_active_key(), it always has a refcount
of 1. Hence, it's freed prematurely in sctp_assoc_update(). Simple fix is
to remove that sctp_auth_key_put() from there which fixes these panics.

Fixes: 730fc3d ("[SCTP]: Implete SCTP-AUTH parameter processing")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Zefan Li <lizefan@huawei.com>
ivan19871002 pushed a commit that referenced this issue Nov 26, 2015
…formed packet

commit e40607cbe270a9e8360907cb1e62ddf0736e4864 upstream.

An SCTP server doing ASCONF will panic on malformed INIT ping-of-death
in the form of:

  ------------ INIT[PARAM: SET_PRIMARY_IP] ------------>

While the INIT chunk parameter verification dissects through many things
in order to detect malformed input, it misses to actually check parameters
inside of parameters. E.g. RFC5061, section 4.2.4 proposes a 'set primary
IP address' parameter in ASCONF, which has as a subparameter an address
parameter.

So an attacker may send a parameter type other than SCTP_PARAM_IPV4_ADDRESS
or SCTP_PARAM_IPV6_ADDRESS, param_type2af() will subsequently return 0
and thus sctp_get_af_specific() returns NULL, too, which we then happily
dereference unconditionally through af->from_addr_param().

The trace for the log:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000078
IP: [<ffffffffa01e9c62>] sctp_process_init+0x492/0x990 [sctp]
PGD 0
Oops: 0000 [#1] SMP
[...]
Pid: 0, comm: swapper Not tainted 2.6.32-504.el6.x86_64 #1 Bochs Bochs
RIP: 0010:[<ffffffffa01e9c62>]  [<ffffffffa01e9c62>] sctp_process_init+0x492/0x990 [sctp]
[...]
Call Trace:
 <IRQ>
 [<ffffffffa01f2add>] ? sctp_bind_addr_copy+0x5d/0xe0 [sctp]
 [<ffffffffa01e1fcb>] sctp_sf_do_5_1B_init+0x21b/0x340 [sctp]
 [<ffffffffa01e3751>] sctp_do_sm+0x71/0x1210 [sctp]
 [<ffffffffa01e5c09>] ? sctp_endpoint_lookup_assoc+0xc9/0xf0 [sctp]
 [<ffffffffa01e61f6>] sctp_endpoint_bh_rcv+0x116/0x230 [sctp]
 [<ffffffffa01ee986>] sctp_inq_push+0x56/0x80 [sctp]
 [<ffffffffa01fcc42>] sctp_rcv+0x982/0xa10 [sctp]
 [<ffffffffa01d5123>] ? ipt_local_in_hook+0x23/0x28 [iptable_filter]
 [<ffffffff8148bdc9>] ? nf_iterate+0x69/0xb0
 [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0
 [<ffffffff8148bf86>] ? nf_hook_slow+0x76/0x120
 [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0
[...]

A minimal way to address this is to check for NULL as we do on all
other such occasions where we know sctp_get_af_specific() could
possibly return with NULL.

Fixes: d6de309 ("[SCTP]: Add the handling of "Set Primary IP Address" parameter to INIT")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Zefan Li <lizefan@huawei.com>
ivan19871002 pushed a commit that referenced this issue Nov 26, 2015
An issue was observed when a userspace task exits.
The page which hits error here is the zero page.
In binder mmap, the whole of vma is not mapped.
On a task crash, when debuggerd reads the binder regions,
the unmapped areas fall to do_anonymous_page in handle_pte_fault,
due to the absence of a vm_fault handler. This results in
zero page being mapped. Later in zap_pte_range, vm_normal_page
returns zero page in the case of VM_MIXEDMAP and it results in the
error.

BUG: Bad page map in process mediaserver  pte:9dff379f pmd:9bfbd831
page:c0ed8e60 count:1 mapcount:-1 mapping:  (null) index:0x0
page flags: 0x404(referenced|reserved)
addr:40c3f000 vm_flags:10220051 anon_vma:  (null) mapping:d9fe0764 index:fd
vma->vm_ops->fault:   (null)
vma->vm_file->f_op->mmap: binder_mmap+0x0/0x274
CPU: 0 PID: 1463 Comm: mediaserver Tainted: G        W    3.10.17+ #1
[<c001549c>] (unwind_backtrace+0x0/0x11c) from [<c001200c>] (show_stack+0x10/0x14)
[<c001200c>] (show_stack+0x10/0x14) from [<c0103d78>] (print_bad_pte+0x158/0x190)
[<c0103d78>] (print_bad_pte+0x158/0x190) from [<c01055f0>] (unmap_single_vma+0x2e4/0x598)
[<c01055f0>] (unmap_single_vma+0x2e4/0x598) from [<c010618c>] (unmap_vmas+0x34/0x50)
[<c010618c>] (unmap_vmas+0x34/0x50) from [<c010a9e4>] (exit_mmap+0xc8/0x1e8)
[<c010a9e4>] (exit_mmap+0xc8/0x1e8) from [<c00520f0>] (mmput+0x54/0xd0)
[<c00520f0>] (mmput+0x54/0xd0) from [<c005972c>] (do_exit+0x360/0x990)
[<c005972c>] (do_exit+0x360/0x990) from [<c0059ef0>] (do_group_exit+0x84/0xc0)
[<c0059ef0>] (do_group_exit+0x84/0xc0) from [<c0066de0>] (get_signal_to_deliver+0x4d4/0x548)
[<c0066de0>] (get_signal_to_deliver+0x4d4/0x548) from [<c0011500>] (do_signal+0xa8/0x3b8)

Add a vm_fault handler which returns VM_FAULT_SIGBUS, and prevents the
wrong fallback to do_anonymous_page.

CRs-Fixed: 673147
Change-Id: I43730a51b6c819538b46c5e4dc5c96c8a384098d
Signed-off-by: Vinayak Menon <vinayakm.list@gmail.com>
Patch-mainline: linux-arm-kernel @ 06/02/14, 18:17
Signed-off-by: Vignesh Radhakrishnan <vigneshr@codeaurora.org>
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
ivan19871002 pushed a commit that referenced this issue Nov 26, 2015
While stressing the CPU hotplug path, sometimes we hit a problem
as shown below.

[57056.416774] ------------[ cut here ]------------
[57056.489232] ksoftirqd/1 (14): undefined instruction: pc=c01931e8
[57056.489245] Code: e594a000 eb085236 e15a0000 0a000000 (e7f001f2)
[57056.489259] ------------[ cut here ]------------
[57056.492840] kernel BUG at kernel/kernel/smpboot.c:134!
[57056.513236] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
[57056.519055] Modules linked in: wlan(O) mhi(O)
[57056.523394] CPU: 0 PID: 14 Comm: ksoftirqd/1 Tainted: G        W  O 3.10.0-g3677c61-00008-g180c060 #1
[57056.532595] task: f0c8b000 ti: f0e78000 task.ti: f0e78000
[57056.537991] PC is at smpboot_thread_fn+0x124/0x218
[57056.542750] LR is at smpboot_thread_fn+0x11c/0x218
[57056.547528] pc : [<c01931e8>]    lr : [<c01931e0>]    psr: 200f0013
[57056.547528] sp : f0e79f30  ip : 00000000  fp : 00000000
[57056.558983] r10: 00000001  r9 : 00000000  r8 : f0e78000
[57056.564192] r7 : 00000001  r6 : c1195758  r5 : f0e78000  r4 : f0e5fd00
[57056.570701] r3 : 00000001  r2 : f0e79f20  r1 : 00000000  r0 : 00000000

This issue was always seen in the context of "ksoftirqd". It seems to
be happening because of a potential race condition in __kthread_parkme
where just after completing the parked completion, before the
ksoftirqd task has been scheduled again, it can go into running state.

Fix this by waiting for the task state to parked after waiting the
parked completion.

CRs-Fixed: 659674
Change-Id: If3f0e9b706eeb5d30d5a32f84378d35bb03fe794
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
ivan19871002 pushed a commit that referenced this issue Nov 26, 2015
On ARMv7 CPUs that cache first level page table entries (like the
Cortex-A15), using a reserved ASID while changing the TTBR or flushing
the TLB is unsafe.

This is because the CPU may cache the first level entry as the result of
a speculative memory access while the reserved ASID is assigned. After
the process owning the page tables dies, the memory will be reallocated
and may be written with junk values which can be interpreted as global,
valid PTEs by the processor. This will result in the TLB being populated
with bogus global entries.

This patch avoids the use of a reserved context ID in the v7 switch_mm
and ASID rollover code by temporarily using the swapper_pg_dir pointed
at by TTBR1, which contains only global entries that are not tagged
with ASIDs.

Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Tested-by: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
[catalin.marinas@arm.com: add LPAE support]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Change-Id: I2dd82501dac5ee402765aaa0ffb3f7f577a603c9

ARM: Remove __ARCH_WANT_INTERRUPTS_ON_CTXSW on ASID-capable CPUs

Since the ASIDs must be unique to an mm across all the CPUs in a system,
the __new_context() function needs to broadcast a context reset event to
all the CPUs during ASID allocation if a roll-over occurred. Such IPIs
cannot be issued with interrupts disabled and ARM had to define
__ARCH_WANT_INTERRUPTS_ON_CTXSW.

This patch changes the check_context() function to
check_and_switch_context() called from switch_mm(). In case of
ASID-capable CPUs (ARMv6 onwards), if a new ASID is needed and the
interrupts are disabled, it defers the __new_context() and
cpu_switch_mm() calls to the post-lock switch hook where the interrupts
are enabled. Setting the reserved TTBR0 was also moved to
check_and_switch_context() from cpu_v7_switch_mm().

Reviewed-by: Will Deacon <will.deacon@arm.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Tested-by: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Conflicts:
	arch/arm/mm/proc-v7-2level.S

Change-Id: I48e39730c49ff8d30ce566e8a03cf54557869a52

ARM: Remove current_mm per-cpu variable

The current_mm variable was used to store the new mm between the
switch_mm() and switch_to() calls where an IPI to reset the context
could have set the wrong mm. Since the interrupts are disabled during
context switch, there is no need for this variable, current->active_mm
already points to the current mm when interrupts are re-enabled.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Tested-by: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

ARM: 7502/1: contextidr: avoid using bfi instruction during notifier

The bfi instruction is not available on ARMv6, so instead use an and/orr
sequence in the contextidr_notifier. This gets rid of the assembler
error:

  Assembler messages:
  Error: selected processor does not support ARM mode `bfi r3,r2,#0,MiCode#8'

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Conflicts:
	arch/arm/mm/context.c

Change-Id: Id64c0145d0dcd1cfe9e2aba59f86c08ec5fbf649

ARM: mm: remove IPI broadcasting on ASID rollover

ASIDs are allocated to MMU contexts based on a rolling counter. This
means that after 255 allocations we must invalidate all existing ASIDs
via an expensive IPI mechanism to synchronise all of the online CPUs and
ensure that all tasks execute with an ASID from the new generation.

This patch changes the rollover behaviour so that we rely instead on the
hardware broadcasting of the TLB invalidation to avoid the IPI calls.
This works by keeping track of the active ASID on each core, which is
then reserved in the case of a rollover so that currently scheduled
tasks can continue to run. For cores without hardware TLB broadcasting,
we keep track of pending flushes in a cpumask, so cores can flush their
local TLB before scheduling a new mm.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Conflicts:
	arch/arm/mm/context.c

Change-Id: I58990400aaaaef35319f7b3fb2f84fe7e46cb581

ARM: mm: avoid taking ASID spinlock on fastpath

When scheduling a new mm, we take a spinlock so that we can:

  1. Safely allocate a new ASID, if required
  2. Update our active_asids field without worrying about parallel
     updates to reserved_asids
  3. Ensure that we flush our local TLB, if required

However, this has the nasty affect of serialising context-switch across
all CPUs in the system. The usual (fast) case is where the next mm has
a valid ASID for the current generation. In such a scenario, we can
avoid taking the lock and instead use atomic64_xchg to update the
active_asids variable for the current CPU. If a rollover occurs on
another CPU (which would take the lock), when copying the active_asids
into the reserved_asids another atomic64_xchg is used to replace each
active_asids with 0. The fast path can then detect this case and fall
back to spinning on the lock.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

ARM: mm: use bitmap operations when allocating new ASIDs

When allocating a new ASID, we must take care not to re-assign a
reserved ASID-value to a new mm. This requires us to check each
candidate ASID against those currently reserved by other cores before
assigning a new ASID to the current mm.

This patch improves the ASID allocation algorithm by using a
bitmap-based approach. Rather than iterating over the reserved ASID
array for each candidate ASID, we simply find the first zero bit,
ensuring that those indices corresponding to reserved ASIDs are set
when flushing during a rollover event.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

ARM: 7649/1: mm: mm->context.id fix for big-endian

Since the new ASID code in b5466f8
("ARM: mm: remove IPI broadcasting on ASID rollover") was changed to
use 64bit operations it has broken the BE operation due to an issue
with the MM code accessing sub-fields of mm->context.id.

When running in BE mode we see the values in mm->context.id are stored
with the highest value first, so the LDR in the arch/arm/mm/proc-macros.S
reads the wrong part of this field. To resolve this, change the LDR in
the mmid macro to load from +4.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7658/1: mm: fix race updating mm->context.id on ASID rollover

If a thread triggers an ASID rollover, other threads of the same process
must be made to wait until the mm->context.id for the shared mm_struct
has been updated to new generation and associated book-keeping (e.g.
TLB invalidation) has ben performed.

However, there is a *tiny* window where both mm->context.id and the
relevant active_asids entry are updated to the new generation, but the
TLB flush has not been performed, which could allow another thread to
return to userspace with a dirty TLB, potentially leading to data
corruption. In reality this will never occur because one CPU would need
to perform a context-switch in the time it takes another to do a couple
of atomic test/set operations but we should plug the race anyway.

This patch moves the active_asids update until after the potential TLB
flush on context-switch.

Cc: <stable@vger.kernel.org> # 3.8
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7659/1: mm: make mm->context.id an atomic64_t variable

mm->context.id is updated under asid_lock when a new ASID is allocated
to an mm_struct. However, it is also read without the lock when a task
is being scheduled and checking whether or not the current ASID
generation is up-to-date.

If two threads of the same process are being scheduled in parallel and
the bottom bits of the generation in their mm->context.id match the
current generation (that is, the mm_struct has not been used for ~2^24
rollovers) then the non-atomic, lockless access to mm->context.id may
yield the incorrect ASID.

This patch fixes this issue by making mm->context.id and atomic64_t,
ensuring that the generation is always read consistently. For code that
only requires access to the ASID bits (e.g. TLB flushing by mm), then
the value is accessed directly, which GCC converts to an ldrb.

Cc: <stable@vger.kernel.org> # 3.8
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Conflicts:
	arch/arm/include/asm/mmu.h

Change-Id: I682895d6357a91ecc439c8543fa94f1aecbfcb4c

ARM: 7661/1: mm: perform explicit branch predictor maintenance when required

The ARM ARM requires branch predictor maintenance if, for a given ASID,
the instructions at a specific virtual address appear to change.

From the kernel's point of view, that means:

	- Changing the kernel's view of memory (e.g. switching to the
	  identity map)
	- ASID rollover (since ASIDs will be re-allocated to new tasks)

This patch adds explicit branch predictor maintenance when either of the
two conditions above are met.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7684/1: errata: Workaround for Cortex-A15 erratum 798181 (TLBI/DSB operations)

On Cortex-A15 (r0p0..r3p2) the TLBI/DSB are not adequately shooting down
all use of the old entries. This patch implements the erratum workaround
which consists of:

1. Dummy TLBIMVAIS and DSB on the CPU doing the TLBI operation.
2. Send IPI to the CPUs that are running the same mm (and ASID) as the
   one being invalidated (or all the online CPUs for global pages).
3. CPU receiving the IPI executes a DMB and CLREX (part of the exception
   return code already).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Conflicts:
	arch/arm/Kconfig

Change-Id: I4513d042301a1faad817b83434280462cc176df1

msm: rtb: Log the context id in the rtb

Store the context id in the register trace buffer.
The process id can be derived from the context id.
This gives a general idea about what process was last
running when the RTB stopped.

Change-Id: I2fb8934d008b8cf3666f1df2652846c15faca776
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
(cherry picked from commit 445eb9a)

Conflicts:

	arch/arm/mach-msm/include/mach/msm_rtb.h

ARM: 7767/1: let the ASID allocator handle suspended animation

commit ae120d9edfe96628f03d87634acda0bfa7110632 upstream.

When a CPU is running a process, the ASID for that process is
held in a per-CPU variable (the "active ASIDs" array). When
the ASID allocator handles a rollover, it copies the active
ASIDs into a "reserved ASIDs" array to ensure that a process
currently running on another CPU will continue to run unaffected.
The active array is zero-ed to indicate that a rollover occurred.

Because of this mechanism, a reserved ASID is only remembered for
a single rollover. A subsequent rollover will completely refill
the reserved ASIDs array.

In a severely oversubscribed environment where a CPU can be
prevented from running for extended periods of time (think virtual
machines), the above has a horrible side effect:

[P{a} denotes process P running with ASID a]

	CPU-0		CPU-1

	A{x}				[active = <x 0>]

	[suspended]	runs B{y}	[active = <x y>]

					[rollover:
					 active = <0 0>
					 reserved = <x y>]

			runs B{y}	[active = <0 y>
					 reserved = <x y>]

					[rollover:
					 active = <0 0>
					 reserved = <0 y>]

			runs C{x}	[active = <0 x>]

	[resumes]

	runs A{x}

At that stage, both A and C have the same ASID, with deadly
consequences.

The fix is to preserve reserved ASIDs across rollovers if
the CPU doesn't have an active ASID when the rollover occurs.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Carinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: 7768/1: prevent risks of out-of-bound access in ASID allocator

commit b8e4a4740fa2b17c0a447b3ab783b3dc10702e27 upstream.

On a CPU that never ran anything, both the active and reserved ASID
fields are set to zero. In this case the ASID_TO_IDX() macro will
return -1, which is not a very useful value to index a bitmap.

Instead of trying to offset the ASID so that ASID #1 is actually
bit 0 in the asid_map bitmap, just always ignore bit 0 and start
the search from bit 1. This makes the code a bit more readable,
and without risk of OoB access.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: 7703/1: Disable preemption in broadcast_tlb*_a15_erratum()

Commit 93dc688 (ARM: 7684/1: errata: Workaround for Cortex-A15 erratum
798181 (TLBI/DSB operations)) introduces calls to smp_processor_id() and
smp_call_function_many() with preemption enabled. This patch disables
preemption and also optimises the smp_processor_id() call in
broadcast_tlb_mm_a15_erratum(). The broadcast_tlb_a15_erratum() function
is changed to use smp_call_function() which disables preemption.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Geoff Levand <geoff@infradead.org>
Reported-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: 7769/1: Cortex-A15: fix erratum 798181 implementation

commit 0d0752bca1f9a91fb646647aa4abbb21156f316c upstream.

Looking into the active_asids array is not enough, as we also need
to look into the reserved_asids array (they both represent processes
that are currently running).

Also, not holding the ASID allocator lock is racy, as another CPU
could schedule that process and trigger a rollover, making the erratum
workaround miss an IPI.

Exposing this outside of context.c is a little ugly on the side, so
let's define a new entry point that the erratum workaround can call
to obtain the cpumask.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arm: mm: Clean ASID patchset

Change-Id: Id5b0cc6d5300d293e33baf6603453bde0df6d6d8

android/lowmemorykiller: Ignore tasks with freed mm

A killed task can stay in the task list long after its
memory has been returned to the system, therefore
ignore any tasks whose mm struct has been freed.

Change-Id: I76394b203b4ab2312437c839976f0ecb7b6dde4e
CRs-fixed: 450383
Signed-off-by: Liam Mark <lmark@codeaurora.org>

Conflicts:
	arch/arm/kernel/smp.c
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