[34-longterm 057/179] x86/amd-iommu: Fix 3 possible endless loops

[Paul Gortmaker]

From: Joerg Roedel <joerg.roedel@xxxxxxx>

                   -------------------
    This is a commit scheduled for the next v2.6.34 longterm release.
    http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
    If you see a problem with using this for longterm, please comment.
                   -------------------

commit 0de66d5b35ee148455e268b2782873204ffdef4b upstream.

The driver contains several loops counting on an u16 value
where the exit-condition is checked against variables that
can have values up to 0xffff. In this case the loops will
never exit. This patch fixed 3 such loops.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
 arch/x86/kernel/amd_iommu_init.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index fa749f7..82571af 100644
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -649,8 +649,8 @@ static void __init init_iommu_from_acpi(struct amd_iommu *iommu,
 {
 	u8 *p = (u8 *)h;
 	u8 *end = p, flags = 0;
-	u16 dev_i, devid = 0, devid_start = 0, devid_to = 0;
-	u32 ext_flags = 0;
+	u16 devid = 0, devid_start = 0, devid_to = 0;
+	u32 dev_i, ext_flags = 0;
 	bool alias = false;
 	struct ivhd_entry *e;
 
@@ -805,7 +805,7 @@ static void __init init_iommu_from_acpi(struct amd_iommu *iommu,
 /* Initializes the device->iommu mapping for the driver */
 static int __init init_iommu_devices(struct amd_iommu *iommu)
 {
-	u16 i;
+	u32 i;
 
 	for (i = iommu->first_device; i <= iommu->last_device; ++i)
 		set_iommu_for_device(iommu, i);
@@ -1094,7 +1094,7 @@ static int __init init_memory_definitions(struct acpi_table_header *table)
  */
 static void init_device_table(void)
 {
-	u16 devid;
+	u32 devid;
 
 	for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) {
 		set_dev_entry_bit(devid, DEV_ENTRY_VALID);
-- 
1.7.9.6

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