diff options
| author | Jann Horn <jannh@google.com> | 2019-02-20 17:54:43 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-03-23 20:11:17 +0100 |
| commit | 020c90c694dc36b345eeecc59ac48eae88faa983 (patch) | |
| tree | c4c0b1cbf96df32488350d332ba661ed9beb5499 /kernel | |
| parent | aca126f4a451b36fc6841d7bf76b3a5f4e5d3b01 (diff) | |
| download | blackbird-obmc-linux-020c90c694dc36b345eeecc59ac48eae88faa983.tar.gz blackbird-obmc-linux-020c90c694dc36b345eeecc59ac48eae88faa983.zip | |
tracing/perf: Use strndup_user() instead of buggy open-coded version
commit 83540fbc8812a580b6ad8f93f4c29e62e417687e upstream.
The first version of this method was missing the check for
`ret == PATH_MAX`; then such a check was added, but it didn't call kfree()
on error, so there was still a small memory leak in the error case.
Fix it by using strndup_user() instead of open-coding it.
Link: http://lkml.kernel.org/r/20190220165443.152385-1-jannh@google.com
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 0eadcc7a7bc0 ("perf/core: Fix perf_uprobe_init()")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace_event_perf.c | 16 |
1 files changed, 7 insertions, 9 deletions
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 76217bbef815..4629a6104474 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -299,15 +299,13 @@ int perf_uprobe_init(struct perf_event *p_event, if (!p_event->attr.uprobe_path) return -EINVAL; - path = kzalloc(PATH_MAX, GFP_KERNEL); - if (!path) - return -ENOMEM; - ret = strncpy_from_user( - path, u64_to_user_ptr(p_event->attr.uprobe_path), PATH_MAX); - if (ret == PATH_MAX) - return -E2BIG; - if (ret < 0) - goto out; + + path = strndup_user(u64_to_user_ptr(p_event->attr.uprobe_path), + PATH_MAX); + if (IS_ERR(path)) { + ret = PTR_ERR(path); + return (ret == -EINVAL) ? -E2BIG : ret; + } if (path[0] == '\0') { ret = -EINVAL; goto out; |
