From f8bf2aeb651b3460a4b36fd7ba1ba1d31777d35c Mon Sep 17 00:00:00 2001 From: James Sewart Date: Tue, 10 Dec 2019 15:51:33 -0600 Subject: PCI: Fix pci_add_dma_alias() bitmask size The number of possible devfns is 256, but pci_add_dma_alias() allocated a bitmap of size 255. Fix this off-by-one error. This fixes commits 338c3149a221 ("PCI: Add support for multiple DMA aliases") and c6635792737b ("PCI: Allocate dma_alias_mask with bitmap_zalloc()"), but I doubt it was possible to see a problem because it takes 4 64-bit longs (or 8 32-bit longs) to hold 255 bits, and bitmap_zalloc() doesn't save the 255-bit size anywhere. [bhelgaas: commit log, move #define to drivers/pci/pci.h, include loop limit fix from Qian Cai: https://lore.kernel.org/r/20191218170004.5297-1-cai@lca.pw] Signed-off-by: James Sewart Signed-off-by: Bjorn Helgaas Reviewed-by: Logan Gunthorpe --- drivers/pci/pci.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/pci/pci.h') diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index a0a53bd05a0b..6394e7746fb5 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -4,6 +4,9 @@ #include +/* Number of possible devfns: 0.0 to 1f.7 inclusive */ +#define MAX_NR_DEVFNS 256 + #define PCI_FIND_CAP_TTL 48 #define PCI_VSEC_ID_INTEL_TBT 0x1234 /* Thunderbolt */ -- cgit v1.2.3