diff options
| author | Petr Tesarik | 2023-11-08 12:12:49 +0100 |
|---|---|---|
| committer | Christoph Hellwig | 2023-11-08 16:27:05 +0100 |
| commit | 53c87e846e335e3c18044c397cc35178163d7827 (patch) | |
| tree | 7b2f6c380c31187cc3067bc2607d0ef948d6c63e /kernel | |
| parent | a409d9600959f3c4b2a48946304c8e01b8d04072 (diff) | |
swiotlb: fix out-of-bounds TLB allocations with CONFIG_SWIOTLB_DYNAMIC
Limit the free list length to the size of the IO TLB. Transient pool can be
smaller than IO_TLB_SEGSIZE, but the free list is initialized with the
assumption that the total number of slots is a multiple of IO_TLB_SEGSIZE.
As a result, swiotlb_area_find_slots() may allocate slots past the end of
a transient IO TLB buffer.
Reported-by: Niklas Schnelle <schnelle@linux.ibm.com>
Closes: https://lore.kernel.org/linux-iommu/104a8c8fedffd1ff8a2890983e2ec1c26bff6810.camel@linux.ibm.com/
Fixes: 79636caad361 ("swiotlb: if swiotlb is full, fall back to a transient memory pool")
Cc: stable@vger.kernel.org
Signed-off-by: Petr Tesarik <petr.tesarik1@huawei-partners.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/dma/swiotlb.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 71392c9fac10..33d942615be5 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -283,7 +283,8 @@ static void swiotlb_init_io_tlb_pool(struct io_tlb_pool *mem, phys_addr_t start, } for (i = 0; i < mem->nslabs; i++) { - mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); + mem->slots[i].list = min(IO_TLB_SEGSIZE - io_tlb_offset(i), + mem->nslabs - i); mem->slots[i].orig_addr = INVALID_PHYS_ADDR; mem->slots[i].alloc_size = 0; } |