Re: [External] : Re: [PATCH] devargs: Fix crash due to global devargs uninitailization from secondary process

[Thomas Monjalon <thomas@monjalon.net>]

15/02/2022 12:20, Madhuker Mythri:
> From: Ferruh Yigit <ferruh.yigit@intel.com> 
> >On 2/14/2022 5:08 PM, madhuker.mythri@oracle.com wrote:
> >> From: Madhuker Mythri <madhuker.mythri@oracle.com>
> >> 
> >> Failsafe pmd started crashing with global devargs syntax as devargs is 
> >> not memset to zero. Access it to in rte_devargs_parse() resulted in a 
> >> crash when called from secondary process.
> >> 
> >> Bugzilla Id: 933
> >> 
> >> Signed-off-by: Madhuker Mythri <madhuker.mythri@oracle.com>
> >
> >This is duplication of Gaetan's patch:
> >https://urldefense.com/v3/__https://patches.dpdk.org/project/dpdk/patch/20220210170131.2199922-1->grive@u256.net/__;!!ACWV5N9M2RV99hQ!aE5DMiBds1eptcxnoYR6KWszXGgqYHaQduFAfUDwH4ps-h0eJIQ5Wk2JBZGMFh5DBZSZ$ 
> 
> Hi Ferruh,
> 
> Initially, I had filed this bug: https://bugs.dpdk.org/show_bug.cgi?id=933 , as part of the testing on Azure/Hyper-V platforms.
> After analysis, found the root-cause of this crash is due to global devargs un-initialization in failsafe-pmd probe() and published the patch as follows:
> https://patchwork.dpdk.org/project/dpdk/patch/20220210071052.527-1-madhuker.mythri@oracle.com/
> 
> From your review comments got to know, that we can memset inside the rte_devargs_parse(), instead of setting outside before this API call.
> Got delayed in testing the same code changes on Azure/Hyper-V platforms and publishing this patch.
> So, please consider this patch, as I had found the root-cause of this issue and tested on affected platforms.
> 
> Thanks,
> Madhuker.

Applied with these explanations from Gaetan:

devargs: fix crash with uninitialized parsing

The function rte_devargs_parse() previously was safe to call with
non-initialized devargs structure as parameter.

When adding the support for the global device syntax,
this assumption was broken.
Restore it by forcing memset as part of the call itself.

Bugzilla ID: 933
Fixes: b344eb5d941a ("devargs: parse global device syntax")
Cc: stable@dpdk.org

Signed-off-by: Madhuker Mythri <madhuker.mythri@oracle.com>
Signed-off-by: Gaetan Rivet <grive@u256.net>

Thanks all