Messages in this thread | | | From | (Eric W. Biederman) | Date | Mon, 10 Jul 2017 06:19:32 -0500 | Subject | Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to refcount_t |
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Alexey Dobriyan <adobriyan@gmail.com> writes:
> On Mon, Jul 10, 2017 at 11:37 AM, Eric W. Biederman > <ebiederm@xmission.com> wrote: >> "Reshetova, Elena" <elena.reshetova@intel.com> writes: >> >> 2>> Elena Reshetova <elena.reshetova@intel.com> writes: >>>> >>>> > refcount_t type and corresponding API should be >>>> > used instead of atomic_t when the variable is used as >>>> > a reference counter. This allows to avoid accidental >>>> > refcounter overflows that might lead to use-after-free >>>> > situations. >>>> >>>> In this patch you can see all of the uses of the count. >>>> What accidental refcount overflows are possible? >>> >>> Even if one can guarantee and prove that in the current implementation >>> there are no overflows possible, we can't say that for >>> sure for any future implementation. Bugs might always happen >>> unfortunately, but if we convert the refcounter to a safer >>> type we can be sure that overflows are not possible. >>> >>> Does it make sense to you? >> >> Not for code that is likely to remain unchanged for a decade no. >> >> This looks like a large set of unautomated changes without any real >> thought put into it. That almost always results in a typo somewhere >> that breaks things. > > This is nonsense. The wrong code would simply emit a warning > which are caught very quickly.
That depends on the typo.
Eric
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