From: Chris Wilson chris@chris-wilson.co.uk
commit 29aaebbca4abc4cceb38738483051abefafb6950 upstream.
Beware that the address size for x86-32 may exceed unsigned long.
[ 0.368971] UBSAN: shift-out-of-bounds in drivers/iommu/intel/iommu.c:128:14 [ 0.369055] shift exponent 36 is too large for 32-bit type 'long unsigned int'
If we don't handle the wide addresses, the pages are mismapped and the device read/writes go astray, detected as DMAR faults and leading to device failure. The behaviour changed (from working to broken) in commit fa954e683178 ("iommu/vt-d: Delegate the dma domain to upper layer"), but the error looks older.
Fixes: fa954e683178 ("iommu/vt-d: Delegate the dma domain to upper layer") Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Acked-by: Lu Baolu baolu.lu@linux.intel.com Cc: James Sewart jamessewart@arista.com Cc: Lu Baolu baolu.lu@linux.intel.com Cc: Joerg Roedel jroedel@suse.de Cc: stable@vger.kernel.org # v5.3+ Link: https://lore.kernel.org/r/20200822160209.28512-1-chris@chris-wilson.co.uk Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/iommu/intel/iommu.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
--- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -123,29 +123,29 @@ static inline unsigned int level_to_offs return (level - 1) * LEVEL_STRIDE; }
-static inline int pfn_level_offset(unsigned long pfn, int level) +static inline int pfn_level_offset(u64 pfn, int level) { return (pfn >> level_to_offset_bits(level)) & LEVEL_MASK; }
-static inline unsigned long level_mask(int level) +static inline u64 level_mask(int level) { - return -1UL << level_to_offset_bits(level); + return -1ULL << level_to_offset_bits(level); }
-static inline unsigned long level_size(int level) +static inline u64 level_size(int level) { - return 1UL << level_to_offset_bits(level); + return 1ULL << level_to_offset_bits(level); }
-static inline unsigned long align_to_level(unsigned long pfn, int level) +static inline u64 align_to_level(u64 pfn, int level) { return (pfn + level_size(level) - 1) & level_mask(level); }
static inline unsigned long lvl_to_nr_pages(unsigned int lvl) { - return 1 << min_t(int, (lvl - 1) * LEVEL_STRIDE, MAX_AGAW_PFN_WIDTH); + return 1UL << min_t(int, (lvl - 1) * LEVEL_STRIDE, MAX_AGAW_PFN_WIDTH); }
/* VT-d pages must always be _smaller_ than MM pages. Otherwise things