lkml.org 
[lkml]   [2017]   [Apr]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH v3 3/7] kprobes: validate the symbol name length
Date
"Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> writes:

> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index 6a128f3a7ed1..bb86681c8a10 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -1382,6 +1382,28 @@ bool within_kprobe_blacklist(unsigned long addr)
> return false;
> }
>
> +bool is_valid_kprobe_symbol_name(const char *name)
> +{
> + size_t sym_len;
> + char *s;
> +
> + s = strchr(name, ':');
> + if (s) {
> + sym_len = strnlen(s+1, KSYM_NAME_LEN);
> + if (sym_len <= 0 || sym_len >= KSYM_NAME_LEN)
> + return false;
> + sym_len = (size_t)(s - name);
> + if (sym_len <= 0 || sym_len >= MODULE_NAME_LEN)
> + return false;
> + } else {
> + sym_len = strnlen(name, MODULE_NAME_LEN);
> + if (sym_len <= 0 || sym_len >= MODULE_NAME_LEN)
> + return false;
> + }

I think this is probably more elaborate than it needs to be.

Why not just check the string is <= (MODULE_NAME_LEN + KSYM_NAME_LEN) ?

cheers

\
 
 \ /
  Last update: 2017-04-20 08:09    [W:0.245 / U:0.084 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site