19/03/2026 13:43, Morten Brørup:
> The sum of offset + length, both 32 bit unsigned integers, could wrap
> around, causing comparisons to give the wrong result.
> This was fixed by using 64 bit instead of 32 bit for calculating the sum.
>
> Note:
> When the branch is not taken for the initial "if ((uint64_t)off + len >
> rte_pktmbuf_pkt_len(m))" comparison, the sum is known to not exceed the
> maximum possible value of rte_pktmbuf_pkt_len(m), UINT32_MAX, and
> following sum calculations can proceed using 32 bit.
>
> Also, fixed a related bug in an mbuf test case:
> It expected reading a length of UINT_MAX from a non-zero offset to not
> fail.
> And due to the offset+length wraparound bug, the read operation did not
> fail.
> This test case was updated to expect the read operation to fail.
>
> Fixes: b84110e7baa2 ("mbuf: add function to read packet data")
> Fixes: 7b295dceea07 ("test/mbuf: add unit test cases")
> Cc: [email protected]
>
> Signed-off-by: Morten Brørup <[email protected]>
Acked-by: Konstantin Ananyev <[email protected]>
Acked-by: Marat Khalili <[email protected]>
Tested-by: Marat Khalili <[email protected]>
Applied, thanks.
