From a1b7f2f6367944d445c6853035830a35c6343939 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Thu, 26 Feb 2015 09:55:03 +0100 Subject: [PATCH] PCI/AER: Avoid info leak in __print_tlp_header() 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 Signed-off-by: Bjorn Helgaas Acked-by: Borislav Petkov CC: stable@vger.kernel.org # v3.14+ --- 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, -- 2.20.1