Messages in this thread | | | Subject | Re: [PATCH v2] bnxt: avoid overflow in bnxt_get_nvram_directory() | From | Paolo Abeni <> | Date | Thu, 23 Feb 2023 09:01:20 +0100 |
| |
On Tue, 2023-02-21 at 10:34 +0100, Paolo Abeni wrote: > On Sun, 2023-02-19 at 15:14 +0100, Simon Horman wrote: > > On Sun, Feb 19, 2023 at 11:46:56AM +0300, Maxim Korotkov wrote: > > > The value of an arithmetic expression is subject > > > of possible overflow due to a failure to cast operands to a larger data > > > type before performing arithmetic. Used macro for multiplication instead > > > operator for avoiding overflow. > > > > > > Found by Security Code and Linux Verification > > > Center (linuxtesting.org) with SVACE. > > > > > > Fixes: c0c050c58d84 ("bnxt_en: New Broadcom ethernet driver.") > > > Signed-off-by: Maxim Korotkov <korotkov.maxim.s@gmail.com> > > > Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com> > > > > I agree that it is correct to use mul_u32_u32() for multiplication > > of two u32 entities where the result is 64bit, avoiding overflow. > > > > And I agree that the fixes tag indicates the commit where the code > > in question was introduced. > > > > However, it is not clear to me if this is a theoretical bug > > or one that can manifest in practice - I think it implies that > > buflen really can be > 4Gbytes. > > > > And thus it is not clear to me if this patch should be for 'net' or > > 'net-next'. > > ... especially considered that both 'dir_entries' and 'entry_length' > are copied back to the user-space using a single byte each.
To be clear: if this is really a bug you should update the commit message stating how the bug could happen. Otherwise you could repost for net-next stripping the fixes tag.
Thanks,
Paolo
| |