From: Mariusz Kozlowski <mk@lab.zgora.pl>
Date: Mon, 22 Nov 2010 19:37:21 +0000 (-0800)
Subject: ide: fix use after free in ide-acpi
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=ba5787323d38084b30261e84510d4a173fcb493a;p=mv-sheeva.git

ide: fix use after free in ide-acpi

out_obj points to kfreed memory and we dereference that pointer in
DEBPRINT/printk.

Signed-off-by: Mariusz Kozlowski <mk@lab.zgora.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/ide/ide-acpi.c b/drivers/ide/ide-acpi.c
index c26c11905ff..2af8cb460a3 100644
--- a/drivers/ide/ide-acpi.c
+++ b/drivers/ide/ide-acpi.c
@@ -416,21 +416,21 @@ void ide_acpi_get_timing(ide_hwif_t *hwif)
 
 	out_obj = output.pointer;
 	if (out_obj->type != ACPI_TYPE_BUFFER) {
-		kfree(output.pointer);
 		DEBPRINT("Run _GTM: error: "
 		       "expected object type of ACPI_TYPE_BUFFER, "
 		       "got 0x%x\n", out_obj->type);
+		kfree(output.pointer);
 		return;
 	}
 
 	if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
 	    out_obj->buffer.length != sizeof(struct GTM_buffer)) {
-		kfree(output.pointer);
 		printk(KERN_ERR
 			"%s: unexpected _GTM length (0x%x)[should be 0x%zx] or "
 			"addr (0x%p)\n",
 			__func__, out_obj->buffer.length,
 			sizeof(struct GTM_buffer), out_obj->buffer.pointer);
+		kfree(output.pointer);
 		return;
 	}