trace/kprobes: Sanitize derived event names

When we derive event names, convert some expected symbols (such as ':'
used to specify module:name and '.' present in some symbols) into
underscores so that the event name is not rejected.

Before this patch:
    # echo 'p kobject_example:foo_store' > kprobe_events
    trace_kprobe: Failed to allocate trace_probe.(-22)
    -sh: write error: Invalid argument

After this patch:
    # echo 'p kobject_example:foo_store' > kprobe_events
    # cat kprobe_events
    p:kprobes/p_kobject_example_foo_store_0 kobject_example:foo_store

Link: http://lkml.kernel.org/r/66c189e09e71361aba91dd4a5bd146a1b62a7a51.1499453040.git.naveen.n.rao@linux.vnet.ibm.com

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Naveen N. Rao 2017-07-08 00:27:30 +05:30 committed by Steven Rostedt (VMware)
parent 29b1a8ad7d
commit fca18a47cf

View File

@ -598,6 +598,14 @@ static struct notifier_block trace_kprobe_module_nb = {
.priority = 1 /* Invoked after kprobe module callback */
};
/* Convert certain expected symbols into '_' when generating event names */
static inline void sanitize_event_name(char *name)
{
while (*name++ != '\0')
if (*name == ':' || *name == '.')
*name = '_';
}
static int create_trace_kprobe(int argc, char **argv)
{
/*
@ -740,6 +748,7 @@ static int create_trace_kprobe(int argc, char **argv)
else
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
is_return ? 'r' : 'p', addr);
sanitize_event_name(buf);
event = buf;
}
tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive,