uprobes/tracing: Fix dentry/mount leak in create_trace_uprobe()

create_trace_uprobe() does kern_path() to find ->d_inode, but forgets
to do path_put(). We can do this right after igrab().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 17d9b2b..06c22ba 100644 (file)
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -253,16 +253,18 @@ static int create_trace_uprobe(int argc, char **argv)
        if (ret)
                goto fail_address_parse;
 
-       ret = kstrtoul(arg, 0, &offset);
-       if (ret)
-               goto fail_address_parse;
-
        inode = igrab(path.dentry->d_inode);
+       path_put(&path);
+
        if (!S_ISREG(inode->i_mode)) {
                ret = -EINVAL;
                goto fail_address_parse;
        }
 
+       ret = kstrtoul(arg, 0, &offset);
+       if (ret)
+               goto fail_address_parse;
+
        argc -= 2;
        argv += 2;