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  1. 09 4月, 2015 1 次提交
    • L
      Copy the kernel module data from user space in chunks · 3afe9f84
      由 Linus Torvalds 提交于 
      Unlike most (all?) other copies from user space, kernel module loading
is almost unlimited in size.  So we do a potentially huge
"copy_from_user()" when we copy the module data from user space to the
kernel buffer, which can be a latency concern when preemption is
disabled (or voluntary).

Also, because 'copy_from_user()' clears the tail of the kernel buffer on
failures, even a *failed* copy can end up wasting a lot of time.

Normally neither of these are concerns in real life, but they do trigger
when doing stress-testing with trinity.  Running in a VM seems to add
its own overheadm causing trinity module load testing to even trigger
the watchdog.

The simple fix is to just chunk up the module loading, so that it never
tries to copy insanely big areas in one go.  That bounds the latency,
and also the amount of (unnecessarily, in this case) cleared memory for
the failure case.
Reported-by: NSasha Levin <sasha.levin@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3afe9f84
  3. 23 3月, 2015 1 次提交
    • P
      lockdep: Fix the module unload key range freeing logic · 35a9393c
      由 Peter Zijlstra 提交于 
      Module unload calls lockdep_free_key_range(), which removes entries
from the data structures. Most of the lockdep code OTOH assumes the
data structures are append only; in specific see the comments in
add_lock_to_list() and look_up_lock_class().

Clearly this has only worked by accident; make it work proper. The
actual scenario to make it go boom would involve the memory freed by
the module unlock being re-allocated and re-used for a lock inside of
a rcu-sched grace period. This is a very unlikely scenario, still
better plug the hole.

Use RCU list iteration in all places and ammend the comments.

Change lockdep_free_key_range() to issue a sync_sched() between
removal from the lists and returning -- which results in the memory
being freed. Further ensure the callers are placed correctly and
comment the requirements.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Tsyvarev <tsyvarev@ispras.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
      35a9393c
  5. 13 3月, 2015 1 次提交
    • A
      kasan, module, vmalloc: rework shadow allocation for modules · a5af5aa8
      由 Andrey Ryabinin 提交于 
      Current approach in handling shadow memory for modules is broken.

Shadow memory could be freed only after memory shadow corresponds it is no
longer used.  vfree() called from interrupt context could use memory its
freeing to store 'struct llist_node' in it:

    void vfree(const void *addr)
    {
    ...
        if (unlikely(in_interrupt())) {
            struct vfree_deferred *p = this_cpu_ptr(&vfree_deferred);
            if (llist_add((struct llist_node *)addr, &p->list))
                    schedule_work(&p->wq);

Later this list node used in free_work() which actually frees memory.
Currently module_memfree() called in interrupt context will free shadow
before freeing module's memory which could provoke kernel crash.

So shadow memory should be freed after module's memory.  However, such
deallocation order could race with kasan_module_alloc() in module_alloc().

Free shadow right before releasing vm area.  At this point vfree()'d
memory is not used anymore and yet not available for other allocations.
New VM_KASAN flag used to indicate that vm area has dynamically allocated
shadow memory so kasan frees shadow only if it was previously allocated.
Signed-off-by: NAndrey Ryabinin <a.ryabinin@samsung.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a5af5aa8
  7. 06 3月, 2015 1 次提交
  9. 18 2月, 2015 1 次提交
  11. 14 2月, 2015 1 次提交
    • A
      kasan: enable instrumentation of global variables · bebf56a1
      由 Andrey Ryabinin 提交于 
      This feature let us to detect accesses out of bounds of global variables.
This will work as for globals in kernel image, so for globals in modules.
Currently this won't work for symbols in user-specified sections (e.g.
__init, __read_mostly, ...)

The idea of this is simple.  Compiler increases each global variable by
redzone size and add constructors invoking __asan_register_globals()
function.  Information about global variable (address, size, size with
redzone ...) passed to __asan_register_globals() so we could poison
variable's redzone.

This patch also forces module_alloc() to return 8*PAGE_SIZE aligned
address making shadow memory handling (
kasan_module_alloc()/kasan_module_free() ) more simple.  Such alignment
guarantees that each shadow page backing modules address space correspond
to only one module_alloc() allocation.
Signed-off-by: NAndrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: NAndrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      bebf56a1
  13. 11 2月, 2015 2 次提交
  15. 06 2月, 2015 2 次提交
  17. 22 1月, 2015 1 次提交
  19. 20 1月, 2015 3 次提交
    • R
      module: fix race in kallsyms resolution during module load success. · c7496379
      由 Rusty Russell 提交于 
      The kallsyms routines (module_symbol_name, lookup_module_* etc) disable
preemption to walk the modules rather than taking the module_mutex:
this is because they are used for symbol resolution during oopses.

This works because there are synchronize_sched() and synchronize_rcu()
in the unload and failure paths.  However, there's one case which doesn't
have that: the normal case where module loading succeeds, and we free
the init section.

We don't want a synchronize_rcu() there, because it would slow down
module loading: this bug was introduced in 2009 to speed module
loading in the first place.

Thus, we want to do the free in an RCU callback.  We do this in the
simplest possible way by allocating a new rcu_head: if we put it in
the module structure we'd have to worry about that getting freed.
Reported-by: NRui Xiang <rui.xiang@huawei.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      c7496379
    • R
      module: remove mod arg from module_free, rename module_memfree(). · be1f221c
      由 Rusty Russell 提交于 
      Nothing needs the module pointer any more, and the next patch will
call it from RCU, where the module itself might no longer exist.
Removing the arg is the safest approach.

This just codifies the use of the module_alloc/module_free pattern
which ftrace and bpf use.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: x86@kernel.org
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: linux-cris-kernel@axis.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: nios2-dev@lists.rocketboards.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Cc: netdev@vger.kernel.org
      be1f221c
    • R
      module_arch_freeing_init(): new hook for archs before module->module_init freed. · d453cded
      由 Rusty Russell 提交于 
      Archs have been abusing module_free() to clean up their arch-specific
allocations.  Since module_free() is also (ab)used by BPF and trace code,
let's keep it to simple allocations, and provide a hook called before
that.

This means that avr32, ia64, parisc and s390 no longer need to implement
their own module_free() at all.  avr32 doesn't need module_finalize()
either.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
      d453cded
  21. 11 11月, 2014 6 次提交
  23. 28 10月, 2014 1 次提交
  25. 15 10月, 2014 1 次提交
    • P
      modules, lock around setting of MODULE_STATE_UNFORMED · d3051b48
      由 Prarit Bhargava 提交于 
      A panic was seen in the following sitation.

There are two threads running on the system. The first thread is a system
monitoring thread that is reading /proc/modules. The second thread is
loading and unloading a module (in this example I'm using my simple
dummy-module.ko).  Note, in the "real world" this occurred with the qlogic
driver module.

When doing this, the following panic occurred:

 ------------[ cut here ]------------
 kernel BUG at kernel/module.c:3739!
 invalid opcode: 0000 [#1] SMP
 Modules linked in: binfmt_misc sg nfsv3 rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel lrw igb gf128mul glue_helper iTCO_wdt iTCO_vendor_support ablk_helper ptp sb_edac cryptd pps_core edac_core shpchp i2c_i801 pcspkr wmi lpc_ich ioatdma mfd_core dca ipmi_si nfsd ipmi_msghandler auth_rpcgss nfs_acl lockd sunrpc xfs libcrc32c sr_mod cdrom sd_mod crc_t10dif crct10dif_common mgag200 syscopyarea sysfillrect sysimgblt i2c_algo_bit drm_kms_helper ttm isci drm libsas ahci libahci scsi_transport_sas libata i2c_core dm_mirror dm_region_hash dm_log dm_mod [last unloaded: dummy_module]
 CPU: 37 PID: 186343 Comm: cat Tainted: GF          O--------------   3.10.0+ #7
 Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013
 task: ffff8807fd2d8000 ti: ffff88080fa7c000 task.ti: ffff88080fa7c000
 RIP: 0010:[<ffffffff810d64c5>]  [<ffffffff810d64c5>] module_flags+0xb5/0xc0
 RSP: 0018:ffff88080fa7fe18  EFLAGS: 00010246
 RAX: 0000000000000003 RBX: ffffffffa03b5200 RCX: 0000000000000000
 RDX: 0000000000001000 RSI: ffff88080fa7fe38 RDI: ffffffffa03b5000
 RBP: ffff88080fa7fe28 R08: 0000000000000010 R09: 0000000000000000
 R10: 0000000000000000 R11: 000000000000000f R12: ffffffffa03b5000
 R13: ffffffffa03b5008 R14: ffffffffa03b5200 R15: ffffffffa03b5000
 FS:  00007f6ae57ef740(0000) GS:ffff88101e7a0000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000404f70 CR3: 0000000ffed48000 CR4: 00000000001407e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Stack:
  ffffffffa03b5200 ffff8810101e4800 ffff88080fa7fe70 ffffffff810d666c
  ffff88081e807300 000000002e0f2fbf 0000000000000000 ffff88100f257b00
  ffffffffa03b5008 ffff88080fa7ff48 ffff8810101e4800 ffff88080fa7fee0
 Call Trace:
  [<ffffffff810d666c>] m_show+0x19c/0x1e0
  [<ffffffff811e4d7e>] seq_read+0x16e/0x3b0
  [<ffffffff812281ed>] proc_reg_read+0x3d/0x80
  [<ffffffff811c0f2c>] vfs_read+0x9c/0x170
  [<ffffffff811c1a58>] SyS_read+0x58/0xb0
  [<ffffffff81605829>] system_call_fastpath+0x16/0x1b
 Code: 48 63 c2 83 c2 01 c6 04 03 29 48 63 d2 eb d9 0f 1f 80 00 00 00 00 48 63 d2 c6 04 13 2d 41 8b 0c 24 8d 50 02 83 f9 01 75 b2 eb cb <0f> 0b 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41
 RIP  [<ffffffff810d64c5>] module_flags+0xb5/0xc0
  RSP <ffff88080fa7fe18>

    Consider the two processes running on the system.

    CPU 0 (/proc/modules reader)
    CPU 1 (loading/unloading module)

    CPU 0 opens /proc/modules, and starts displaying data for each module by
    traversing the modules list via fs/seq_file.c:seq_open() and
    fs/seq_file.c:seq_read().  For each module in the modules list, seq_read
    does

            op->start()  <-- this is a pointer to m_start()
            op->show()   <- this is a pointer to m_show()
            op->stop()   <-- this is a pointer to m_stop()

    The m_start(), m_show(), and m_stop() module functions are defined in
    kernel/module.c. The m_start() and m_stop() functions acquire and release
    the module_mutex respectively.

    ie) When reading /proc/modules, the module_mutex is acquired and released
    for each module.

    m_show() is called with the module_mutex held.  It accesses the module
    struct data and attempts to write out module data.  It is in this code
    path that the above BUG_ON() warning is encountered, specifically m_show()
    calls

    static char *module_flags(struct module *mod, char *buf)
    {
            int bx = 0;

            BUG_ON(mod->state == MODULE_STATE_UNFORMED);
    ...

    The other thread, CPU 1, in unloading the module calls the syscall
    delete_module() defined in kernel/module.c.  The module_mutex is acquired
    for a short time, and then released.  free_module() is called without the
    module_mutex.  free_module() then sets mod->state = MODULE_STATE_UNFORMED,
    also without the module_mutex.  Some additional code is called and then the
    module_mutex is reacquired to remove the module from the modules list:

        /* Now we can delete it from the lists */
        mutex_lock(&module_mutex);
        stop_machine(__unlink_module, mod, NULL);
        mutex_unlock(&module_mutex);

This is the sequence of events that leads to the panic.

CPU 1 is removing dummy_module via delete_module().  It acquires the
module_mutex, and then releases it.  CPU 1 has NOT set dummy_module->state to
MODULE_STATE_UNFORMED yet.

CPU 0, which is reading the /proc/modules, acquires the module_mutex and
acquires a pointer to the dummy_module which is still in the modules list.
CPU 0 calls m_show for dummy_module.  The check in m_show() for
MODULE_STATE_UNFORMED passed for dummy_module even though it is being
torn down.

Meanwhile CPU 1, which has been continuing to remove dummy_module without
holding the module_mutex, now calls free_module() and sets
dummy_module->state to MODULE_STATE_UNFORMED.

CPU 0 now calls module_flags() with dummy_module and ...

static char *module_flags(struct module *mod, char *buf)
{
        int bx = 0;

        BUG_ON(mod->state == MODULE_STATE_UNFORMED);

and BOOM.

Acquire and release the module_mutex lock around the setting of
MODULE_STATE_UNFORMED in the teardown path, which should resolve the
problem.

Testing: In the unpatched kernel I can panic the system within 1 minute by
doing

while (true) do insmod dummy_module.ko; rmmod dummy_module.ko; done

and

while (true) do cat /proc/modules; done

in separate terminals.

In the patched kernel I was able to run just over one hour without seeing
any issues.  I also verified the output of panic via sysrq-c and the output
of /proc/modules looks correct for all three states for the dummy_module.

        dummy_module 12661 0 - Unloading 0xffffffffa03a5000 (OE-)
        dummy_module 12661 0 - Live 0xffffffffa03bb000 (OE)
        dummy_module 14015 1 - Loading 0xffffffffa03a5000 (OE+)
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Reviewed-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
      d3051b48
  27. 03 10月, 2014 1 次提交
    • K
      aarch64: filter $x from kallsyms · 6c34f1f5
      由 Kyle McMartin 提交于 
      Similar to ARM, AArch64 is generating $x and $d syms... which isn't
terribly helpful when looking at %pF output and the like. Filter those
out in kallsyms, modpost and when looking at module symbols.

Seems simplest since none of these check EM_ARM anyway, to just add it
to the strchr used, rather than trying to make things overly
complicated.

initcall_debug improves:
dmesg_before.txt: initcall $x+0x0/0x154 [sg] returned 0 after 26331 usecs
dmesg_after.txt: initcall init_sg+0x0/0x154 [sg] returned 0 after 15461 usecs
Signed-off-by: NKyle McMartin <kyle@redhat.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
      6c34f1f5
  29. 27 8月, 2014 1 次提交
  31. 16 8月, 2014 1 次提交
  33. 27 7月, 2014 2 次提交
  35. 03 7月, 2014 1 次提交
    • J
      crypto: fips - only panic on bad/missing crypto mod signatures · 002c77a4
      由 Jarod Wilson 提交于 
      Per further discussion with NIST, the requirements for FIPS state that
we only need to panic the system on failed kernel module signature checks
for crypto subsystem modules. This moves the fips-mode-only module
signature check out of the generic module loading code, into the crypto
subsystem, at points where we can catch both algorithm module loads and
mode module loads. At the same time, make CONFIG_CRYPTO_FIPS dependent on
CONFIG_MODULE_SIG, as this is entirely necessary for FIPS mode.

v2: remove extraneous blank line, perform checks in static inline
function, drop no longer necessary fips.h include.

CC: "David S. Miller" <davem@davemloft.net>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Stephan Mueller <stephan.mueller@atsec.com>
Signed-off-by: NJarod Wilson <jarod@redhat.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
      002c77a4
  37. 14 5月, 2014 1 次提交
    • R
      module: set nx before marking module MODULE_STATE_COMING. · 4982223e
      由 Rusty Russell 提交于 
      We currently set RO & NX on modules very late: after we move them from
MODULE_STATE_UNFORMED to MODULE_STATE_COMING, and after we call
parse_args() (which can exec code in the module).

Much better is to do it in complete_formation() and then call
the notifier.

This means that the notifiers will be called on a module which
is already RO & NX, so that may cause problems (ftrace already
changed so they're unaffected).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      4982223e
  39. 28 4月, 2014 3 次提交
    • S
      ftrace/module: Hardcode ftrace_module_init() call into load_module() · a949ae56
      由 Steven Rostedt (Red Hat) 提交于 
      A race exists between module loading and enabling of function tracer.

	CPU 1				CPU 2
	-----				-----
  load_module()
   module->state = MODULE_STATE_COMING

				register_ftrace_function()
				 mutex_lock(&ftrace_lock);
				 ftrace_startup()
				  update_ftrace_function();
				   ftrace_arch_code_modify_prepare()
				    set_all_module_text_rw();
				   <enables-ftrace>
				    ftrace_arch_code_modify_post_process()
				     set_all_module_text_ro();

				[ here all module text is set to RO,
				  including the module that is
				  loading!! ]

   blocking_notifier_call_chain(MODULE_STATE_COMING);
    ftrace_init_module()

     [ tries to modify code, but it's RO, and fails!
       ftrace_bug() is called]

When this race happens, ftrace_bug() will produces a nasty warning and
all of the function tracing features will be disabled until reboot.

The simple solution is to treate module load the same way the core
kernel is treated at boot. To hardcode the ftrace function modification
of converting calls to mcount into nops. This is done in init/main.c
there's no reason it could not be done in load_module(). This gives
a better control of the changes and doesn't tie the state of the
module to its notifiers as much. Ftrace is special, it needs to be
treated as such.

The reason this would work, is that the ftrace_module_init() would be
called while the module is in MODULE_STATE_UNFORMED, which is ignored
by the set_all_module_text_ro() call.

Link: http://lkml.kernel.org/r/1395637826-3312-1-git-send-email-indou.takao@jp.fujitsu.comReported-by: NTakao Indoh <indou.takao@jp.fujitsu.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: stable@vger.kernel.org # 2.6.38+
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      a949ae56
    • R
      param: hand arguments after -- straight to init · 51e158c1
      由 Rusty Russell 提交于 
      The kernel passes any args it doesn't need through to init, except it
assumes anything containing '.' belongs to the kernel (for a module).
This change means all users can clearly distinguish which arguments
are for init.

For example, the kernel uses debug ("dee-bug") to mean log everything to
the console, where systemd uses the debug from the Scandinavian "day-boog"
meaning "fail to boot".  If a future versions uses argv[] instead of
reading /proc/cmdline, this confusion will be avoided.

eg: test 'FOO="this is --foo"' -- 'systemd.debug="true true true"'

Gives:
argv[0] = '/debug-init'
argv[1] = 'test'
argv[2] = 'systemd.debug=true true true'
envp[0] = 'HOME=/'
envp[1] = 'TERM=linux'
envp[2] = 'FOO=this is --foo'
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      51e158c1
    • R
      module: remove warning about waiting module removal. · 79465d2f
      由 Rusty Russell 提交于 
      We remove the waiting module removal in commit 3f2b9c9c (September
2013), but it turns out that modprobe in kmod (< version 16) was
asking for waiting module removal.  No one noticed since modprobe would
check for 0 usage immediately before trying to remove the module, and
the race is unlikely.

However, it means that anyone running old (but not ancient) kmod
versions is hitting the printk designed to see if anyone was running
"rmmod -w".  All reports so far have been false positives, so remove
the warning.

Fixes: 3f2b9c9cReported-by: NValerio Vanni <valerio.vanni@inwind.it>
Cc: Elliott, Robert (Server Storage) <Elliott@hp.com>
Cc: stable@kernel.org
Acked-by: NLucas De Marchi <lucas.de.marchi@gmail.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      79465d2f
  41. 08 4月, 2014 1 次提交
  43. 31 3月, 2014 1 次提交
    • R
      Use 'E' instead of 'X' for unsigned module taint flag. · 57673c2b
      由 Rusty Russell 提交于 
      Takashi Iwai <tiwai@suse.de> says:
> The letter 'X' has been already used for SUSE kernels for very long
> time, to indicate the external supported modules.  Can the new flag be
> changed to another letter for avoiding conflict...?
> (BTW, we also use 'N' for "no support", too.)

Note: this code should be cleaned up, so we don't have such maps in
three places!
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      57673c2b
  45. 21 3月, 2014 1 次提交
  47. 13 3月, 2014 2 次提交
    • M
      Fix: module signature vs tracepoints: add new TAINT_UNSIGNED_MODULE · 66cc69e3
      由 Mathieu Desnoyers 提交于 
      Users have reported being unable to trace non-signed modules loaded
within a kernel supporting module signature.

This is caused by tracepoint.c:tracepoint_module_coming() refusing to
take into account tracepoints sitting within force-loaded modules
(TAINT_FORCED_MODULE). The reason for this check, in the first place, is
that a force-loaded module may have a struct module incompatible with
the layout expected by the kernel, and can thus cause a kernel crash
upon forced load of that module on a kernel with CONFIG_TRACEPOINTS=y.

Tracepoints, however, specifically accept TAINT_OOT_MODULE and
TAINT_CRAP, since those modules do not lead to the "very likely system
crash" issue cited above for force-loaded modules.

With kernels having CONFIG_MODULE_SIG=y (signed modules), a non-signed
module is tainted re-using the TAINT_FORCED_MODULE taint flag.
Unfortunately, this means that Tracepoints treat that module as a
force-loaded module, and thus silently refuse to consider any tracepoint
within this module.

Since an unsigned module does not fit within the "very likely system
crash" category of tainting, add a new TAINT_UNSIGNED_MODULE taint flag
to specifically address this taint behavior, and accept those modules
within Tracepoints. We use the letter 'X' as a taint flag character for
a module being loaded that doesn't know how to sign its name (proposed
by Steven Rostedt).

Also add the missing 'O' entry to trace event show_module_flags() list
for the sake of completeness.
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
NAKed-by: NIngo Molnar <mingo@redhat.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: David Howells <dhowells@redhat.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      66cc69e3
    • J
      module: use pr_cont · 27bba4d6
      由 Jiri Slaby 提交于 
      When dumping loaded modules, we print them one by one in separate
printks. Let's use pr_cont as they are continuation prints.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      27bba4d6
  49. 14 2月, 2014 1 次提交
  51. 21 1月, 2014 1 次提交
  53. 13 11月, 2013 1 次提交