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author | Li Zefan <lizf@cn.fujitsu.com> | 2009-06-16 16:39:41 +0800 |
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committer | Steven Rostedt <rostedt@goodmis.org> | 2009-06-16 16:25:37 -0400 |
commit | 00e95830a4d6e49f764fdb19896a89199bc0aa3b (patch) | |
tree | 972a3872cb48474777da0f9e3121fcc6924e197d /samples/trace_events | |
parent | 57be88878e7aa38750384704d811485a607bbda4 (diff) | |
download | linux-00e95830a4d6e49f764fdb19896a89199bc0aa3b.tar.bz2 |
tracing/filters: fix race between filter setting and module unload
Module unload is protected by event_mutex, while setting filter is
protected by filter_mutex. This leads to the race:
echo 'bar == 0 || bar == 10' \ |
> sample/filter |
| insmod sample.ko
add_pred("bar == 0") |
-> n_preds == 1 |
add_pred("bar == 100") |
-> n_preds == 2 |
| rmmod sample.ko
| insmod sample.ko
add_pred("&&") |
-> n_preds == 1 (should be 3) |
Now event->filter->preds is corrupted. An then when filter_match_preds()
is called, the WARN_ON() in it will be triggered.
To avoid the race, we remove filter_mutex, and replace it with event_mutex.
[ Impact: prevent corruption of filters by module removing and loading ]
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A375A4D.6000205@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'samples/trace_events')
0 files changed, 0 insertions, 0 deletions