| Message ID | 20181025135231.27817-1-colin.king@canonical.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | x86/PCI: Fix Broadcom CNB20LE unintended sign extension (redux) | expand |
On Thu, Oct 25, 2018 at 02:52:31PM +0100, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > > In the expression "word1 << 16", word1 starts as u16, but is promoted to > a signed int, then sign-extended to resource_size_t, which is probably > not what was intended. Cast to resource_size_t to avoid the sign > extension. > > This fixes an identical issue as fixed by commit 0b2d70764bb3 > ("x86/PCI: Fix Broadcom CNB20LE unintended sign extension") back in 2014. > > Detected by CoverityScan, CID#138749, 138750 ("Unintended sign extension") > > Fixes: 3f6ea84a3035 ("PCI: read memory ranges out of Broadcom CNB20LE host bridge") > Signed-off-by: Colin Ian King <colin.king@canonical.com> How lame that I fixed one but not both with 0b2d70764bb3, sorry about that! Applied to pci/enumeration for v4.21, thanks! > --- > arch/x86/pci/broadcom_bus.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/pci/broadcom_bus.c b/arch/x86/pci/broadcom_bus.c > index 526536c81ddc..d09c401a300d 100644 > --- a/arch/x86/pci/broadcom_bus.c > +++ b/arch/x86/pci/broadcom_bus.c > @@ -50,8 +50,8 @@ static void __init cnb20le_res(u8 bus, u8 slot, u8 func) > word1 = read_pci_config_16(bus, slot, func, 0xc0); > word2 = read_pci_config_16(bus, slot, func, 0xc2); > if (word1 != word2) { > - res.start = (word1 << 16) | 0x0000; > - res.end = (word2 << 16) | 0xffff; > + res.start = ((resource_size_t) word1 << 16) | 0x0000; > + res.end = ((resource_size_t) word2 << 16) | 0xffff; > res.flags = IORESOURCE_MEM; > update_res(info, res.start, res.end, res.flags, 0); > } > -- > 2.19.1 >
diff --git a/arch/x86/pci/broadcom_bus.c b/arch/x86/pci/broadcom_bus.c index 526536c81ddc..d09c401a300d 100644 --- a/arch/x86/pci/broadcom_bus.c +++ b/arch/x86/pci/broadcom_bus.c @@ -50,8 +50,8 @@ static void __init cnb20le_res(u8 bus, u8 slot, u8 func) word1 = read_pci_config_16(bus, slot, func, 0xc0); word2 = read_pci_config_16(bus, slot, func, 0xc2); if (word1 != word2) { - res.start = (word1 << 16) | 0x0000; - res.end = (word2 << 16) | 0xffff; + res.start = ((resource_size_t) word1 << 16) | 0x0000; + res.end = ((resource_size_t) word2 << 16) | 0xffff; res.flags = IORESOURCE_MEM; update_res(info, res.start, res.end, res.flags, 0); }