linux/kernel
Alexei Starovoitov 8d3b7dce86 bpf: add support for %s specifier to bpf_trace_printk()
%s specifier makes bpf program and kernel debugging easier.
To make sure that trace_printk won't crash the unsafe string
is copied into stack and unsafe pointer is substituted.

The following C program:
 #include <linux/fs.h>
int foo(struct pt_regs *ctx, struct filename *filename)
{
  void *name = 0;

  bpf_probe_read(&name, sizeof(name), &filename->name);
  bpf_trace_printk("executed %s\n", name);
  return 0;
}

when attached to kprobe do_execve()
will produce output in /sys/kernel/debug/tracing/trace_pipe :
    make-13492 [002] d..1  3250.997277: : executed /bin/sh
      sh-13493 [004] d..1  3250.998716: : executed /usr/bin/gcc
     gcc-13494 [002] d..1  3250.999822: : executed /usr/lib/gcc/x86_64-linux-gnu/4.7/cc1
     gcc-13495 [002] d..1  3251.006731: : executed /usr/bin/as
     gcc-13496 [002] d..1  3251.011831: : executed /usr/lib/gcc/x86_64-linux-gnu/4.7/collect2
collect2-13497 [000] d..1  3251.012941: : executed /usr/bin/ld

Suggested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28 16:27:27 -07:00
..
bpf bpf: fix bpf_perf_event_read() loop upper bound 2015-08-12 16:42:50 -07:00
configs kconfig: add xenconfig defconfig helper 2015-06-16 11:04:29 +01:00
debug
events Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-08-21 11:44:04 -07:00
gcov gcov: add support for GCC 5.1 2015-06-30 19:44:57 -07:00
irq genirq: Introduce irq_chip_set_type_parent() helper 2015-08-20 00:25:25 +02:00
livepatch Merge branches 'for-4.1/upstream-fixes', 'for-4.2/kaslr' and 'for-4.2/upstream' into for-linus 2015-06-22 16:26:56 +02:00
locking locking/pvqspinlock: Fix kernel panic in locking-selftest 2015-07-21 10:18:07 +02:00
power Power management and ACPI fixes for v4.2-rc1 2015-07-01 14:17:44 -07:00
printk printk: improve the description of /dev/kmsg line format 2015-06-30 19:44:59 -07:00
rcu This patch series contains several clean ups and even a new trace clock 2015-06-26 14:02:43 -07:00
sched sched/fair: Test list head instead of list entry in throttle_cfs_rq() 2015-07-06 14:15:08 +02:00
time timer: Write timer->flags atomically 2015-08-18 15:31:16 +02:00
trace bpf: add support for %s specifier to bpf_trace_printk() 2015-08-28 16:27:27 -07:00
.gitignore
Kconfig.freezer
Kconfig.hz
Kconfig.locks locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS 2015-05-12 09:46:00 +02:00
Kconfig.preempt
Makefile make certificate list change message more useful 2015-07-02 16:42:13 -07:00
acct.c
async.c
audit.c Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit 2015-06-27 13:53:16 -07:00
audit.h
audit_tree.c
audit_watch.c
auditfilter.c
auditsc.c Fix broken audit tests for exec arg len 2015-07-08 09:33:38 -07:00
backtracetest.c
bounds.c
capability.c
cgroup.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2015-07-03 15:20:57 -07:00
cgroup_freezer.c
compat.c compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap() 2015-06-04 23:57:18 +02:00
configs.c
context_tracking.c context_tracking: Inherit TIF_NOHZ through forks instead of context switches 2015-05-07 12:02:51 +02:00
cpu.c genirq: Revert sparse irq locking around __cpu_up() and move it to x86 for now 2015-07-15 10:39:17 +02:00
cpu_pm.c
cpuset.c cpuset: use trialcs->mems_allowed as a temp variable 2015-08-10 11:18:41 -04:00
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c exit,stats: /* obey this comment */ 2015-06-25 17:00:43 -07:00
extable.c
fork.c x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86 2015-07-18 03:42:51 +02:00
freezer.c
futex.c Merge branch 'sched-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-06-24 14:46:01 -07:00
futex_compat.c
groups.c
hung_task.c
irq_work.c
jump_label.c module, jump_label: Fix module locking 2015-05-27 11:09:50 +09:30
kallsyms.c
kcmp.c
kexec.c kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path 2015-06-30 19:44:57 -07:00
kmod.c
kprobes.c
ksysfs.c
kthread.c kthread: export kthread functions 2015-08-07 04:39:41 +03:00
latencytop.c
module-internal.h
module.c module: weaken locking assertion for oops path. 2015-07-29 06:13:22 +09:30
module_signing.c
notifier.c
nsproxy.c
padata.c
panic.c kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path 2015-06-30 19:44:57 -07:00
params.c Minor merge needed, due to function move. 2015-07-01 10:49:25 -07:00
pid.c
pid_namespace.c
profile.c
ptrace.c
range.c
reboot.c
relay.c kernel/relay.c: use kvfree() in relay_free_page_array() 2015-06-30 19:44:59 -07:00
resource.c mm: Fix bugs in region_is_ram() 2015-07-22 17:20:34 +02:00
seccomp.c seccomp, filter: add and use bpf_prog_create_from_user from seccomp 2015-05-09 17:35:05 -04:00
signal.c signal: fix information leak in copy_siginfo_to_user 2015-08-07 04:39:40 +03:00
smp.c
smpboot.c watchdog: add watchdog_cpumask sysctl to assist nohz 2015-06-24 17:49:40 -07:00
smpboot.h
softirq.c
stacktrace.c
stop_machine.c sched/stop_machine: Fix deadlock between multiple stop_two_cpus() 2015-06-19 10:03:12 +02:00
sys.c prctl: more prctl(PR_SET_MM_*) checks 2015-06-25 17:00:37 -07:00
sys_ni.c
sysctl.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2015-07-03 15:20:57 -07:00
sysctl_binary.c
system_certificates.S
system_keyring.c
task_work.c
taskstats.c
test_kprobes.c
torture.c rcu: Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE() 2015-05-27 12:56:15 -07:00
tracepoint.c
tsacct.c
uid16.c
up.c
user-return-notifier.c
user.c
user_namespace.c
utsname.c
utsname_sysctl.c
watchdog.c watchdog: add watchdog_cpumask sysctl to assist nohz 2015-06-24 17:49:40 -07:00
workqueue.c Minor merge needed, due to function move. 2015-07-01 10:49:25 -07:00
workqueue_internal.h