tree 73bc72332cabb63fb0497ae2f9a6e4b4f93e1a5f
parent 62fc00a6611a0014c85763f9def1fc07c15d1302
author Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> 1527296376 +0900
committer Rafael J. Wysocki <rafael.j.wysocki@intel.com> 1527415202 +0200

PM / hibernate: Fix oops at snapshot_write()

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>