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| author |   James Sewart <jamessewart@arista.com> | 2019-12-10 15:51:33 -0600 |
|---|---|---|
| committer |   Bjorn Helgaas <bhelgaas@google.com> | 2019-12-18 12:21:16 -0600 |
| commit | f8bf2aeb651b3460a4b36fd7ba1ba1d31777d35c (patch) | |
| tree | 202de2282e09e50ca722a0e65f336fee7c36a901 /drivers/pci | |
| parent | PCI/IOV: Fix memory leak in pci_iov_add_virtfn() (diff) | |
| download | linux-dev-f8bf2aeb651b3460a4b36fd7ba1ba1d31777d35c.tar.xz linux-dev-f8bf2aeb651b3460a4b36fd7ba1ba1d31777d35c.zip | |
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 <jamessewart@arista.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/pci.c | 2 | ||||
| -rw-r--r-- | drivers/pci/pci.h | 3 | ||||
| -rw-r--r-- | drivers/pci/search.c | 4 |
3 files changed, 6 insertions, 3 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e87196cc1a7f..7b5fa2eabe09 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -6017,7 +6017,7 @@ EXPORT_SYMBOL_GPL(pci_pr3_present); void pci_add_dma_alias(struct pci_dev *dev, u8 devfn) { if (!dev->dma_alias_mask) - dev->dma_alias_mask = bitmap_zalloc(U8_MAX, GFP_KERNEL); + dev->dma_alias_mask = bitmap_zalloc(MAX_NR_DEVFNS, GFP_KERNEL); if (!dev->dma_alias_mask) { pci_warn(dev, "Unable to allocate DMA alias mask\n"); return; 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 <linux/pci.h> +/* 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 */ diff --git a/drivers/pci/search.c b/drivers/pci/search.c index bade14002fd8..e4dbdef5aef0 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -41,9 +41,9 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, * DMA, iterate over that too. */ if (unlikely(pdev->dma_alias_mask)) { - u8 devfn; + unsigned int devfn; - for_each_set_bit(devfn, pdev->dma_alias_mask, U8_MAX) { + for_each_set_bit(devfn, pdev->dma_alias_mask, MAX_NR_DEVFNS) { ret = fn(pdev, PCI_DEVID(pdev->bus->number, devfn), data); if (ret) |