Commit f0744af7 authored Nov 21, 2012 by Oleg Nesterov

uprobes: Kill the pointless inode/uc checks in register/unregister



register/unregister verifies that inode/uc != NULL. For what?
This really looks like "hide the potential problem", the caller
should pass the valid data.

register() also checks uc->next == NULL, probably to prevent the
double-register but the caller can do other stupid/wrong things.
If we do this check, then we should document that uc->next should
be cleared before register() and add BUG_ON().

Also add the small comment about the i_size_read() check.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>

parent bbc33d05

kernel/events/uprobes.c

+1 −6

Original line number	Diff line number	Diff line
		@@ -844,9 +844,7 @@ int uprobe_register(struct inode inode, loff_t offset, struct uprobe_consumer
		struct uprobe *uprobe;
		int ret;

		if (!inode \|\| !uc \|\| uc->next)
		return -EINVAL;

		/* Racy, just to catch the obvious mistakes */
		if (offset > i_size_read(inode))
		return -EINVAL;

		@@ -883,9 +881,6 @@ void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consume
		{
		struct uprobe *uprobe;

		if (!inode \|\| !uc)
		return;

		uprobe = find_uprobe(inode, offset);
		if (!uprobe)
		return;

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