lkml.org 
[lkml]   [2020]   [Dec]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.19 180/346] PCI: Bounds-check command-line resource alignment requests
    Date
    From: Bjorn Helgaas <bhelgaas@google.com>

    [ Upstream commit 6534aac198b58309ff2337981d3f893e0be1d19d ]

    32-bit BARs are limited to 2GB size (2^31). By extension, I assume 64-bit
    BARs are limited to 2^63 bytes. Limit the alignment requested by the
    "pci=resource_alignment=" command-line parameter to 2^63.

    Link: https://lore.kernel.org/r/20201007123045.GS4282@kadam
    Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
    Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    drivers/pci/pci.c | 14 ++++++++------
    1 file changed, 8 insertions(+), 6 deletions(-)

    diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
    index 57a87a001b4f4..5103d4b140ee3 100644
    --- a/drivers/pci/pci.c
    +++ b/drivers/pci/pci.c
    @@ -5840,19 +5840,21 @@ static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev,
    while (*p) {
    count = 0;
    if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
    - p[count] == '@') {
    + p[count] == '@') {
    p += count + 1;
    + if (align_order > 63) {
    + pr_err("PCI: Invalid requested alignment (order %d)\n",
    + align_order);
    + align_order = PAGE_SHIFT;
    + }
    } else {
    - align_order = -1;
    + align_order = PAGE_SHIFT;
    }

    ret = pci_dev_str_match(dev, p, &p);
    if (ret == 1) {
    *resize = true;
    - if (align_order == -1)
    - align = PAGE_SIZE;
    - else
    - align = 1 << align_order;
    + align = 1 << align_order;
    break;
    } else if (ret < 0) {
    pr_err("PCI: Can't parse resource_alignment parameter: %s\n",
    --
    2.27.0


    \
     
     \ /
      Last update: 2020-12-28 14:40    [W:4.109 / U:0.072 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site