ipc: set msg back to -EAGAIN if copy wasn't performed

Make sure that msg pointer is set back to error value in case of
MSG_COPY flag is set and desired message to copy wasn't found.  This
garantees that msg is either a error pointer or a copy address.

Otherwise the last message in queue will be freed without unlinking from
the queue (which leads to memory corruption) and the dummy allocated
copy won't be released.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Stanislav Kinsbursky 2013-04-01 11:40:51 +04:00 committed by Linus Torvalds
parent 118c9a45fd
commit 2dc958fa2f

View File

@ -872,6 +872,7 @@ long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp,
goto out_unlock;
break;
}
msg = ERR_PTR(-EAGAIN);
} else
break;
msg_counter++;