[PATCH 3/6] uprobes/tracing: Ensure inode != NULL in create_trace_uprobe()

Oleg Nesterov
2013-01-31T19:19:27Z

probe_event_enable/disable() check tu->inode != NULL at the start.
This is ugly, if igrab() can fail create_trace_uprobe() should not
succeed and "postpone" the failure.

Note: alloc_uprobe() should probably check igrab() != NULL as well.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
kernel/trace/trace_uprobe.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 7b75949..f02bbec 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -255,6 +255,8 @@ static int create_trace_uprobe(int argc, char **argv)

inode = igrab(path.dentry->d_inode);
path_put(&path);
+ if (!inode)
+ goto fail_address_parse;

ret = kstrtoul(arg, 0, &offset);
if (ret)
@@ -539,7 +541,7 @@ static int probe_event_enable(struct trace_uprobe *tu, int flag)
struct uprobe_trace_consumer *utc;
int ret = 0;

- if (!tu->inode || tu->consumer)
+ if (tu->consumer)
return -EINTR;

utc = kzalloc(sizeof(struct uprobe_trace_consumer), GFP_KERNEL);
@@ -563,7 +565,7 @@ static int probe_event_enable(struct trace_uprobe *tu, int flag)

static void probe_event_disable(struct trace_uprobe *tu, int flag)
{
- if (!tu->inode || !tu->consumer)
+ if (!tu->consumer)
return;

uprobe_unregister(tu->inode, tu->offset, &tu->consumer->cons);
--
1.5.5.1