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| 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 11:39:32 +0200 |
| commit | 140eae92cf7023422aec3a1647f78c1e0bdd6bf8 (patch) | |
| tree | 2281ba31911675d25c080f7954442c173dba4877 | |
| parent | 6f9f5797fc7de2e9f801b2f7af0726e1349d33a4 (diff) | |
| download | linux-stable-140eae92cf7023422aec3a1647f78c1e0bdd6bf8.tar.gz linux-stable-140eae92cf7023422aec3a1647f78c1e0bdd6bf8.tar.bz2 linux-stable-140eae92cf7023422aec3a1647f78c1e0bdd6bf8.zip | |
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 22df9f7ff672..69017a569f30 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) |