Re: [PATCH 04/10] eal: fix plugin dir walk

[David Marchand <david.marchand@redhat.com>]

On Fri, Jun 20, 2025 at 11:19 AM Bruce Richardson
<bruce.richardson@intel.com> wrote:
>
> On Thu, Jun 19, 2025 at 09:10:30AM +0200, David Marchand wrote:
> > For '.' and '..' directories (or any short file name),
> > a out of bound issue occurs.
> >
> > Caught by UBSan:
> >
> > EAL: Detected shared linkage of DPDK
> > ../lib/eal/common/eal_common_options.c:420:15: runtime error: index -2
> >       out of bounds for type 'char[256]'
> >     #0 0x7f867eedf206 in eal_plugindir_init
> >       eal_common_options.c
> >     #1 0x7f867eede58a in eal_plugins_init
> >       (build/lib/librte_eal.so.25+0xde58a)
> >       (BuildId: e7e4a1935e4bacb51c82ab1a84098a27decf3b4c)
> >     #2 0x7f867efb8587 in rte_eal_init
> >       (build/lib/librte_eal.so.25+0x1b8587)
> >       (BuildId: e7e4a1935e4bacb51c82ab1a84098a27decf3b4c)
> >     #3 0x55b62360861e in main
> >       (/home/runner/work/dpdk/dpdk/build/app/dpdk-testpmd+0x9e061e)
> >       (BuildId: d821ec918612c83fad8b5ccb6cc518e66bee48cd)
> >     #4 0x7f8667429d8f in __libc_start_call_main
> >       csu/../sysdeps/nptl/libc_start_call_main.h:58:16
> >     #5 0x7f8667429e3f in __libc_start_main
> >       csu/../csu/libc-start.c:392:3
> >     #6 0x55b622d9d444 in _start
> >       (/home/runner/work/dpdk/dpdk/build/app/dpdk-testpmd+0x175444)
> >       (BuildId: d821ec918612c83fad8b5ccb6cc518e66bee48cd)
> > SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior
> >       ../lib/eal/common/eal_common_options.c:420:15 in
> >       ../lib/eal/common/eal_common_options.c:421:15:
> >       runtime error: index 18446744073709551609 out of bounds
> >       for type 'char[256]'
> >
> > Fixes: c57f6e5c604a ("eal: fix plugin loading")
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: David Marchand <david.marchand@redhat.com>
> > ---
> Acked-by: Bruce Richardson <bruce.richardson@intel.com>
>
> One thought inline below...
>
> >  lib/eal/common/eal_common_options.c | 15 +++++++++++----
> >  1 file changed, 11 insertions(+), 4 deletions(-)
> >
> > diff --git a/lib/eal/common/eal_common_options.c b/lib/eal/common/eal_common_options.c
> > index 83b6fc7e89..153f807e4f 100644
> > --- a/lib/eal/common/eal_common_options.c
> > +++ b/lib/eal/common/eal_common_options.c
> > @@ -399,6 +399,14 @@ eal_plugins_init(void)
> >  }
> >  #else
> >
> > +static bool
> > +ends_with(const char *str, size_t str_len, const char *tail)
> > +{
> > +     size_t tail_len = strlen(tail);
> > +
> > +     return str_len >= tail_len && strncmp(&str[str_len - tail_len], tail, tail_len) == 0;
> > +}
> > +
>
> I wonder if that function is worth renaming to "rte_str_ends_with" and
> putting in rte_string_fns.h?

I'll have a look and see if we have potential users in the tree.



-- 
David Marchand