Commit 2dc958fa authored Apr 01, 2013 by Stanislav Kinsbursky Committed by Linus Torvalds Apr 02, 2013

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>

parent 118c9a45

ipc/msg.c

+1 −0

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