Tejun Heo
3544d72a0e
ptrace: implement PTRACE_SEIZE ...
PTRACE_ATTACH implicitly issues SIGSTOP on attach which has side
effects on tracee signal and job control states. This patch
implements a new ptrace request PTRACE_SEIZE which attaches a tracee
without trapping it or affecting its signal and job control states.
The usage is the same with PTRACE_ATTACH but it takes PTRACE_SEIZE_*
flags in @data. Currently, the only defined flag is
PTRACE_SEIZE_DEVEL which is a temporary flag to enable PTRACE_SEIZE.
PTRACE_SEIZE will change ptrace behaviors outside of attach itself.
The changes will be implemented gradually and the DEVEL flag is to
prevent programs which expect full SEIZE behavior from using it before
all the behavior modifications are complete while allowing unit
testing. The flag will be removed once SEIZE behaviors are completely
implemented.
* PTRACE_SEIZE, unlike ATTACH, doesn't force tracee to trap. After
attaching tracee continues to run unless a trap condition occurs.
* PTRACE_SEIZE doesn't affect signal or group stop state.
* If PTRACE_SEIZE'd, group stop uses PTRACE_EVENT_STOP trap which uses
exit_code of (signr | PTRACE_EVENT_STOP << 8) where signr is one of
the stopping signals if group stop is in effect or SIGTRAP
otherwise, and returns usual trap siginfo on PTRACE_GETSIGINFO
instead of NULL.
Seizing sets PT_SEIZED in ->ptrace of the tracee. This flag will be
used to determine whether new SEIZE behaviors should be enabled.
Test program follows.
#define PTRACE_SEIZE 0x4206
#define PTRACE_SEIZE_DEVEL 0x80000000
static const struct timespec ts100ms = { .tv_nsec = 100000000 };
static const struct timespec ts1s = { .tv_sec = 1 };
static const struct timespec ts3s = { .tv_sec = 3 };
int main(int argc, char **argv)
{
pid_t tracee;
tracee = fork();
if (tracee == 0) {
nanosleep(&ts100ms, NULL);
while (1) {
printf("tracee: alive\n");
nanosleep(&ts1s, NULL);
}
}
if (argc > 1)
kill(tracee, SIGSTOP);
nanosleep(&ts100ms, NULL);
ptrace(PTRACE_SEIZE, tracee, NULL,
(void *)(unsigned long)PTRACE_SEIZE_DEVEL);
if (argc > 1) {
waitid(P_PID, tracee, NULL, WSTOPPED);
ptrace(PTRACE_CONT, tracee, NULL, NULL);
}
nanosleep(&ts3s, NULL);
printf("tracer: exiting\n");
return 0;
}
When the above program is called w/o argument, tracee is seized while
running and remains running. When tracer exits, tracee continues to
run and print out messages.
# ./test-seize-simple
tracee: alive
tracee: alive
tracee: alive
tracer: exiting
tracee: alive
tracee: alive
When called with an argument, tracee is seized from stopped state and
continued, and returns to stopped state when tracer exits.
# ./test-seize
tracee: alive
tracee: alive
tracee: alive
tracer: exiting
# ps -el|grep test-seize
1 T 0 4720 1 0 80 0 - 941 signal ttyS0 00:00:00 test-seize
-v2: SEIZE doesn't schedule TRAP_STOP and leaves tracee running as Jan
suggested.
-v3: PTRACE_EVENT_STOP traps now report group stop state by signr. If
group stop is in effect the stop signal number is returned as
part of exit_code; otherwise, SIGTRAP. This was suggested by
Denys and Oleg.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
2011-06-16 21:41:53 +02:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
perf: Fix SIGIO handling
2011-05-28 17:04:59 +02:00
Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
2011-03-20 18:14:55 -07:00
irq: Remove smp_affinity_list when unregister irq proc
2011-05-26 13:15:28 +02:00
PM / Hibernate: Update kerneldoc comments in hibernate.c
2011-05-24 23:36:06 +02:00
hrtimers: Avoid touching inactive timer bases
2011-05-23 13:59:54 +02:00
ftrace: Add internal recursive checks
2011-05-25 22:13:49 -04:00
netlink: kill loginuid/sessionid/sid members from struct netlink_skb_parms
2011-03-03 10:55:40 -08:00
audit: make functions static
2010-10-30 01:42:19 -04:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
kill path_lookup()
2011-03-14 09:15:23 -04:00
netlink: kill loginuid/sessionid/sid members from struct netlink_skb_parms
2011-03-03 10:55:40 -08:00
audit: acquire creds selectively to reduce atomic op overhead
2011-04-27 15:11:03 +02:00
memcg: remove direct page_cgroup-to-page pointer
2011-03-23 19:46:28 -07:00
Merge branch 'master' into next
2011-05-19 18:51:57 +10:00
cgroup: remove the ns_cgroup
2011-05-26 17:12:34 -07:00
cgroups: add per-thread subsystem callbacks
2011-05-26 17:12:34 -07:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
2011-05-25 15:35:32 -07:00
llseek: automatically add .llseek fop
2010-10-15 15:53:27 +02:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
cpuset: Fix cpuset_cpus_allowed_fallback(), don't update tsk->rt.nr_cpus_allowed
2011-05-28 17:02:57 +02:00
crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn
2011-03-23 19:47:19 -07:00
Merge branch 'docs-move' of git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs
2011-05-27 10:25:02 -07:00
Merge branch 'ptrace' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc
2011-05-20 13:33:21 -07:00
extable, core_kernel_data(): Make sure all archs define _sdata
2011-05-20 08:56:56 +02:00
mm: Fix boot crash in mm_alloc()
2011-05-29 11:32:28 -07:00
Freezer: Use SMP barriers
2011-05-17 23:19:17 +02:00
futex: Set FLAGS_HAS_TIMEOUT during futex_wait restart setup
2011-04-15 16:34:32 +02:00
userns: user namespaces: convert several capable() calls
2011-03-23 19:47:08 -07:00
userns: user namespaces: convert several capable() calls
2011-03-23 19:47:08 -07:00
hrtimers: Fix typo causing erratic timers
2011-05-25 15:31:58 -07:00
watchdog, hung_task_timeout: Add Kconfig configurable default
2011-04-28 09:13:17 +02:00
irq_work: Use per cpu atomics instead of regular atomics
2010-12-18 15:54:48 +01:00
jump_label: Check entries limit in __jump_label_update
2011-05-25 19:56:36 -04:00
Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2011-03-25 17:52:22 -07:00
arch:Kconfig.locks Remove unused config option.
2011-04-10 17:01:05 +02:00
PM: Remove sysdev suspend, resume and shutdown operations
2011-05-11 21:37:15 +02:00
kfifo: fix scatterlist usage
2010-10-01 10:50:58 -07:00
Merge branch 'next' into for-linus
2011-05-24 22:55:24 +10:00
Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
2011-01-07 17:02:58 -08:00
kernel/ksysfs.c: expose file_caps_enabled in sysfs
2011-04-19 16:45:51 -07:00
cpuset: Fix cpuset_cpus_allowed_fallback(), don't update tsk->rt.nr_cpus_allowed
2011-05-28 17:02:57 +02:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
lockdep: Remove cmpxchg to update nr_chain_hlocks
2011-04-22 11:06:59 +02:00
lockdep: Remove unused 'factor' variable from lockdep_stats_show()
2011-03-23 13:54:47 +01:00
cgroup: remove the ns_cgroup
2011-05-26 17:12:34 -07:00
Merge branch 'staging-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6
2011-05-23 12:49:28 -07:00
mutex: Use p->on_cpu for the adaptive spin
2011-04-14 08:52:33 +02:00
mutex: Use p->on_cpu for the adaptive spin
2011-04-14 08:52:33 +02:00
lockdep, mutex: provide mutex_lock_nest_lock
2011-05-25 08:39:17 -07:00
mutex: Use p->on_cpu for the adaptive spin
2011-04-14 08:52:33 +02:00
cgroup: remove the ns_cgroup
2011-05-26 17:12:34 -07:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
move x86 specific oops=panic to generic code
2011-03-22 17:44:11 -07:00
params.c: Use new strtobool function to process boolean inputs
2011-05-19 16:55:28 +09:30
next_pidmap: fix overflow condition
2011-04-18 10:35:30 -07:00
pidns: call pid_ns_prepare_proc() from create_pid_namespace()
2011-03-23 19:46:58 -07:00
Merge branch 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6
2011-05-29 11:18:09 -07:00
hrtimers: Avoid touching inactive timer bases
2011-05-23 13:59:54 +02:00
posix-timers: RCU conversion
2011-05-24 12:10:51 +02:00
printk: allocate kernel log buffer earlier
2011-05-25 08:39:48 -07:00
kernel/profile.c: remove some duplicate code from profile_hits()
2011-05-26 17:12:37 -07:00
ptrace: implement PTRACE_SEIZE
2011-06-16 21:41:53 +02:00
kernel/range.c: fix clean_sort_range() for the case of full array
2010-11-12 07:55:31 -08:00
rcu: Use WARN_ON_ONCE for DEBUG_OBJECTS_RCU_HEAD warnings
2011-05-05 23:16:57 -07:00
sanitize <linux/prefetch.h> usage
2011-05-20 12:50:29 -07:00
rcu: Converge TINY_RCU expedited and normal boosting
2011-05-05 23:16:58 -07:00
rcu: mark rcutorture boosting callback as being on-stack
2011-05-05 23:16:57 -07:00
rcu: Cure load woes
2011-05-31 10:01:48 +02:00
rcu: Remove waitqueue usage for cpu, node, and boost kthreads
2011-05-28 17:41:52 +02:00
rcu: Cure load woes
2011-05-31 10:01:48 +02:00
rcu: Decrease memory-barrier usage based on semi-formal proof
2011-05-26 09:42:23 -07:00
Clean up relay_alloc_page_array() slightly by using vzalloc rather than vmalloc and memset
2010-11-05 08:21:34 -07:00
memcg: res_counter_read_u64(): fix potential races on 32-bit machines
2011-03-23 19:46:22 -07:00
resources: add arch hook for preventing allocation in reserved areas
2010-12-17 10:01:09 -08:00
rtmutex: Simplify PI algorithm and make highest prio task get lock
2011-01-27 21:13:51 -05:00
rtmutex: tester: Remove the remaining BKL leftovers
2011-02-22 22:07:22 +01:00
rtmutex: Simplify PI algorithm and make highest prio task get lock
2011-01-27 21:13:51 -05:00
rtmutex: Simplify PI algorithm and make highest prio task get lock
2011-01-27 21:13:51 -05:00
cpuset: Fix cpuset_cpus_allowed_fallback(), don't update tsk->rt.nr_cpus_allowed
2011-05-28 17:02:57 +02:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
sched, autogroup: Stop going ahead if autogroup is disabled
2011-02-23 11:33:59 +01:00
sched: Add some clock info to sched_debug
2010-11-23 10:29:08 +01:00
sched: Get rid of lock_depth
2011-04-24 13:18:38 +02:00
sched: Fix ->min_vruntime calculation in dequeue_entity()
2011-05-28 17:02:56 +02:00
sched: Move the second half of ttwu() to the remote cpu
2011-04-14 08:52:41 +02:00
sched: Drop the rq argument to sched_class::select_task_rq()
2011-04-14 08:52:36 +02:00
sched: More sched_domain iterations fixes
2011-05-28 17:02:54 +02:00
sched: More sched_domain iterations fixes
2011-05-28 17:02:54 +02:00
sched: Drop the rq argument to sched_class::select_task_rq()
2011-04-14 08:52:36 +02:00
ptrace: implement PTRACE_SEIZE
2011-06-16 21:41:53 +02:00
smp: move smp setup functions to kernel/smp.c
2011-03-22 17:44:11 -07:00
rcu: move TREE_RCU from softirq to kthread
2011-05-05 23:16:54 -07:00
rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
2011-01-14 04:56:49 -08:00
kthread: use kthread_create_on_node()
2011-03-22 17:44:01 -07:00
Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
2011-05-19 18:24:11 -07:00
ipc: Add missing sys_ni entries for ipc/compat.c functions
2011-05-20 13:53:02 -07:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
2011-05-25 15:35:32 -07:00
open-style analog of vfs_path_lookup()
2011-03-14 09:15:28 -04:00
sysctl_check: drop dead code
2011-03-23 19:46:51 -07:00
taskstats: use appropriate printk priority level
2011-03-23 19:47:14 -07:00
kprobes: Fix selftest to clear flags field for reusing probes
2010-10-14 08:55:27 +02:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2011-03-15 18:53:35 -07:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2011-03-15 18:53:35 -07:00
jump label: Introduce static_branch() interface
2011-04-04 12:48:08 -04:00
taskstats: use real microsecond granularity for CPU times
2010-10-27 18:03:17 -07:00
userns: user namespaces: convert several capable() calls
2011-03-23 19:47:08 -07:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
userns: add a user_namespace as creator/owner of uts_namespace
2011-03-23 19:46:59 -07:00
user_ns: improve the user_ns on-the-slab packaging
2011-01-13 08:03:18 -08:00
ns proc: Add support for the uts namespace
2011-05-10 14:35:35 -07:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
kernel/watchdog.c: Use proper ANSI C prototypes
2011-05-23 21:07:40 -07:00
Merge branch 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
2011-05-24 11:53:42 -07:00
3544d72a0e