diff options
| author | Ben Hutchings <bhutchings@solarflare.com> | 2010-10-08 10:36:10 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-10-08 10:36:10 -0700 |
| commit | 993284dfff3ba4643f08b592427d0ac758d30156 (patch) | |
| tree | e929f5e896bb71d33eca2a6b21774ae93d051344 | |
| parent | 4e7f79511e7332ae4056eda9156a0299511ea41e (diff) | |
sfc: Don't try to set filters with search depths we know won't work
The filter engine will time-out and ignore filters beyond
200-something hops. We also need to avoid infinite loops in
efx_filter_search() when the table is full.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/sfc/filter.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/net/sfc/filter.c b/drivers/net/sfc/filter.c index abc884d09d57..52cb6082b910 100644 --- a/drivers/net/sfc/filter.c +++ b/drivers/net/sfc/filter.c @@ -20,6 +20,12 @@ #define FILTER_CTL_SRCH_FUDGE_WILD 3 #define FILTER_CTL_SRCH_FUDGE_FULL 1 +/* Hard maximum hop limit. Hardware will time-out beyond 200-something. + * We also need to avoid infinite loops in efx_filter_search() when the + * table is full. + */ +#define FILTER_CTL_SRCH_MAX 200 + struct efx_filter_table { u32 offset; /* address of table relative to BAR */ unsigned size; /* number of entries */ @@ -183,7 +189,8 @@ static int efx_filter_search(struct efx_filter_table *table, incr = efx_filter_increment(key); for (depth = 1, filter_idx = hash & (table->size - 1); - test_bit(filter_idx, table->used_bitmap); + depth <= FILTER_CTL_SRCH_MAX && + test_bit(filter_idx, table->used_bitmap); ++depth) { cmp = &table->spec[filter_idx]; if (efx_filter_equal(spec, cmp)) @@ -192,6 +199,8 @@ static int efx_filter_search(struct efx_filter_table *table, } if (!for_insert) return -ENOENT; + if (depth > FILTER_CTL_SRCH_MAX) + return -EBUSY; found: *depth_required = depth; return filter_idx; |