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author | Jann Horn <jannh@google.com> | 2019-02-20 17:54:43 +0100 |
---|---|---|
committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-02-21 10:35:10 -0500 |
commit | 83540fbc8812a580b6ad8f93f4c29e62e417687e (patch) | |
tree | bbced260938642e388e780d28245bea212f25934 | |
parent | b689269bd1bb7b1bffb01c1d2d212e66b54f2eb2 (diff) | |
download | linux-stable-83540fbc8812a580b6ad8f93f4c29e62e417687e.tar.gz linux-stable-83540fbc8812a580b6ad8f93f4c29e62e417687e.tar.bz2 linux-stable-83540fbc8812a580b6ad8f93f4c29e62e417687e.zip |
tracing/perf: Use strndup_user() instead of buggy open-coded version
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>
-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; |