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    SubjectRe: [PATCH v2] PCI/AER: Avoid info leak in __print_tlp_header
    On Thu, Feb 26, 2015 at 09:55:03AM +0100, Rasmus Villemoes wrote:
    > Commit fab4c256a58b ("PCI/AER: Add a TLP header print helper")
    > introduced the helper function __print_tlp_header, but contrary to the
    > intention, the behaviour did change: Since we're taking the address of
    > the parameter t, the first 4 or 8 bytes printed will be the value of
    > the pointer t itself, and the remaining 12 or 8 bytes will be
    > who-knows-what (something from the stack).
    >
    > We want to show the values of the four members of the struct
    > aer_header_log_regs; that can be done without ugly and error-prone
    > casts. On little-endian this should produce the same output as
    > originally intended, and since no-one has complained about getting
    > garbage output so far, I think big-endian should be ok too.
    >
    > Fixes: fab4c256a58b ("PCI/AER: Add a TLP header print helper")
    > Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>

    Applied with Borislav's ack to for-linus for v4.0, thanks! Also added
    stable tag.

    > ---
    > v2: Just print ->dwX as-is.
    >
    > drivers/pci/pcie/aer/aerdrv_errprint.c | 12 ++----------
    > 1 file changed, 2 insertions(+), 10 deletions(-)
    >
    > diff --git a/drivers/pci/pcie/aer/aerdrv_errprint.c b/drivers/pci/pcie/aer/aerdrv_errprint.c
    > index c6849d9e86ce..167fe411ce2e 100644
    > --- a/drivers/pci/pcie/aer/aerdrv_errprint.c
    > +++ b/drivers/pci/pcie/aer/aerdrv_errprint.c
    > @@ -132,16 +132,8 @@ static const char *aer_agent_string[] = {
    > static void __print_tlp_header(struct pci_dev *dev,
    > struct aer_header_log_regs *t)
    > {
    > - unsigned char *tlp = (unsigned char *)&t;
    > -
    > - dev_err(&dev->dev, " TLP Header:"
    > - " %02x%02x%02x%02x %02x%02x%02x%02x"
    > - " %02x%02x%02x%02x %02x%02x%02x%02x\n",
    > - *(tlp + 3), *(tlp + 2), *(tlp + 1), *tlp,
    > - *(tlp + 7), *(tlp + 6), *(tlp + 5), *(tlp + 4),
    > - *(tlp + 11), *(tlp + 10), *(tlp + 9),
    > - *(tlp + 8), *(tlp + 15), *(tlp + 14),
    > - *(tlp + 13), *(tlp + 12));
    > + dev_err(&dev->dev, " TLP Header: %08x %08x %08x %08x\n",
    > + t->dw0, t->dw1, t->dw2, t->dw3);
    > }
    >
    > static void __aer_print_error(struct pci_dev *dev,
    > --
    > 2.1.3
    >


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