diff options
| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2018-05-26 09:59:36 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-07-17 11:37:54 +0200 |
| commit | 34f841a3c3db03dd7de1157c3b1bda07b50d3259 (patch) | |
| tree | f980eef5600d89d7080ae3dfc2486f356085be20 | |
| parent | e3cf1cc9ed9230560e61306e13c88eccb5189c1b (diff) | |
PM / hibernate: Fix oops at snapshot_write()
commit fc14eebfc20854a38fd9f1d93a42b1783dad4d17 upstream.
syzbot is reporting NULL pointer dereference at snapshot_write() [1].
This is because data->handle is zero-cleared by ioctl(SNAPSHOT_FREE).
Fix this by checking data_of(data->handle) != NULL before using it.
[1] https://syzkaller.appspot.com/bug?id=828a3c71bd344a6de8b6a31233d51a72099f27fd
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+ae590932da6e45d6564d@syzkaller.appspotmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/power/user.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/power/user.c b/kernel/power/user.c index 35310b627388..bc6dde1f1567 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -186,6 +186,11 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, res = PAGE_SIZE - pg_offp; } + if (!data_of(data->handle)) { + res = -EINVAL; + goto unlock; + } + res = simple_write_to_buffer(data_of(data->handle), res, &pg_offp, buf, count); if (res > 0) |