From: Gustavo A. R. Silva Date: Wed, 4 Jul 2018 22:20:41 +0000 (-0500) Subject: char: amd64-agp: Use 64-bit arithmetic instead of 32-bit X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=572d8fda26fecbb6bbb63e917b5610c7157cde96;p=linux.git char: amd64-agp: Use 64-bit arithmetic instead of 32-bit Cast *tmp* and *nb_base* to u64 in order to give the compiler complete information about the proper arithmetic to use. Notice that such variables are used in contexts that expect expressions of type u64 (64 bits, unsigned) and the following expressions are currently being evaluated using 32-bit arithmetic: tmp << 25 nb_base << 25 Addresses-Coverity-ID: 200586 ("Unintentional integer overflow") Addresses-Coverity-ID: 200587 ("Unintentional integer overflow") Signed-off-by: Gustavo A. R. Silva Signed-off-by: Dave Airlie --- diff --git a/drivers/char/agp/amd64-agp.c b/drivers/char/agp/amd64-agp.c index e50c29c97ca74..c69e39fdd02b8 100644 --- a/drivers/char/agp/amd64-agp.c +++ b/drivers/char/agp/amd64-agp.c @@ -156,7 +156,7 @@ static u64 amd64_configure(struct pci_dev *hammer, u64 gatt_table) /* Address to map to */ pci_read_config_dword(hammer, AMD64_GARTAPERTUREBASE, &tmp); - aperturebase = tmp << 25; + aperturebase = (u64)tmp << 25; aper_base = (aperturebase & PCI_BASE_ADDRESS_MEM_MASK); enable_gart_translation(hammer, gatt_table); @@ -277,7 +277,7 @@ static int fix_northbridge(struct pci_dev *nb, struct pci_dev *agp, u16 cap) pci_read_config_dword(nb, AMD64_GARTAPERTURECTL, &nb_order); nb_order = (nb_order >> 1) & 7; pci_read_config_dword(nb, AMD64_GARTAPERTUREBASE, &nb_base); - nb_aper = nb_base << 25; + nb_aper = (u64)nb_base << 25; /* Northbridge seems to contain crap. Try the AGP bridge. */