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| author | Tomas Bortoli <tomasbortoli@gmail.com> | 2019-05-28 17:43:38 +0200 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-05-28 16:27:58 -0400 |
| commit | dfb4a6f2191a80c8b790117d0ff592fd712d3296 (patch) | |
| tree | ee5899455d1b43d2736e59c88e355ec4f1c08172 /kernel/trace | |
| parent | 0c97bf863efce63d6ab7971dad811601e6171d2f (diff) | |
| download | lwn-dfb4a6f2191a80c8b790117d0ff592fd712d3296.tar.gz lwn-dfb4a6f2191a80c8b790117d0ff592fd712d3296.zip | |
tracing: Avoid memory leak in predicate_parse()
In case of errors, predicate_parse() goes to the out_free label
to free memory and to return an error code.
However, predicate_parse() does not free the predicates of the
temporary prog_stack array, thence leaking them.
Link: http://lkml.kernel.org/r/20190528154338.29976-1-tomasbortoli@gmail.com
Cc: stable@vger.kernel.org
Fixes: 80765597bc587 ("tracing: Rewrite filter logic to be simpler and faster")
Reported-by: syzbot+6b8e0fb820e570c59e19@syzkaller.appspotmail.com
Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com>
[ Added protection around freeing prog_stack[i].pred ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace_events_filter.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index d3e59312ef40..5079d1db3754 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -428,7 +428,7 @@ predicate_parse(const char *str, int nr_parens, int nr_preds, op_stack = kmalloc_array(nr_parens, sizeof(*op_stack), GFP_KERNEL); if (!op_stack) return ERR_PTR(-ENOMEM); - prog_stack = kmalloc_array(nr_preds, sizeof(*prog_stack), GFP_KERNEL); + prog_stack = kcalloc(nr_preds, sizeof(*prog_stack), GFP_KERNEL); if (!prog_stack) { parse_error(pe, -ENOMEM, 0); goto out_free; @@ -579,7 +579,11 @@ predicate_parse(const char *str, int nr_parens, int nr_preds, out_free: kfree(op_stack); kfree(inverts); - kfree(prog_stack); + if (prog_stack) { + for (i = 0; prog_stack[i].pred; i++) + kfree(prog_stack[i].pred); + kfree(prog_stack); + } return ERR_PTR(ret); } |