Mark, Jason,

On Tue, Jul 21, 2015 at 11:57:39PM +0000, Mark Johnston wrote:
M>   Fix counter reads on platforms where sizeof(uint64_t) != sizeof(uint64_t 
*).
M>   
M>   In the kernel, structs such as tcpstat are manipulated as an array of
M>   counter_u64_t (uint64_t *), but made visible to userland as an array of
M>   uint64_t. kread_counters() was previously copying the counter array into
M>   user space and sequentially overwriting each counter with its value. This
M>   mostly affects IPsec counters, as other counters are exported via sysctl.
M>   
M>   PR:                201700
M>   Tested by: Jason Unovitch

Thanks for fixing the bug after me.

One question, though: why do you use sizeof(u_long) instead of size of a
pointer?

M> 
==============================================================================
M> --- head/usr.bin/netstat/main.c      Tue Jul 21 23:44:36 2015        
(r285781)
M> +++ head/usr.bin/netstat/main.c      Tue Jul 21 23:57:38 2015        
(r285782)
M> @@ -776,19 +776,31 @@ kread_counter(u_long addr)
M>  int
M>  kread_counters(u_long addr, void *buf, size_t size)
M>  {
M> -    uint64_t *c = buf;
M> +    uint64_t *c;
M> +    u_long *counters;
M> +    size_t i, n;
M>  
M>      if (kvmd_init() < 0)
M>              return (-1);
M>  
M> -    if (kread(addr, buf, size) < 0)
M> +    if (size % sizeof(uint64_t) != 0) {
M> +            xo_warnx("kread_counters: invalid counter set size");
M>              return (-1);
M> +    }
M>  
M> -    while (size != 0) {
M> -            *c = kvm_counter_u64_fetch(kvmd, *c);
M> -            size -= sizeof(*c);
M> -            c++;
M> +    n = size / sizeof(uint64_t);
M> +    if ((counters = malloc(n * sizeof(u_long))) == NULL)
M> +            xo_err(-1, "malloc");
M> +    if (kread(addr, counters, n * sizeof(u_long)) < 0) {
M> +            free(counters);
M> +            return (-1);
M>      }
M> +
M> +    c = buf;
M> +    for (i = 0; i < n; i++)
M> +            c[i] = kvm_counter_u64_fetch(kvmd, counters[i]);
M> +
M> +    free(counters);
M>      return (0);
M>  }

-- 
Totus tuus, Glebius.
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