diff options
| -rw-r--r-- | net/ethtool/bitset.c | 48 |
1 files changed, 44 insertions, 4 deletions
diff --git a/net/ethtool/bitset.c b/net/ethtool/bitset.c index 0515d6604b3b..f0883357d12e 100644 --- a/net/ethtool/bitset.c +++ b/net/ethtool/bitset.c @@ -425,12 +425,32 @@ static int ethnl_parse_bit(unsigned int *index, bool *val, unsigned int nbits, return 0; } +/** + * ethnl_bitmap32_equal() - Compare two bitmaps + * @map1: first bitmap + * @map2: second bitmap + * @nbits: bit size to compare + * + * Return: true if first @nbits are equal, false if not + */ +static bool ethnl_bitmap32_equal(const u32 *map1, const u32 *map2, + unsigned int nbits) +{ + if (memcmp(map1, map2, nbits / 32 * sizeof(u32))) + return false; + if (nbits % 32 == 0) + return true; + return !((map1[nbits / 32] ^ map2[nbits / 32]) & + ethnl_lower_bits(nbits % 32)); +} + static int ethnl_update_bitset32_verbose(u32 *bitmap, unsigned int nbits, const struct nlattr *attr, struct nlattr **tb, ethnl_string_array_t names, struct netlink_ext_ack *extack, bool *mod) { + u32 *saved_bitmap = NULL; struct nlattr *bit_attr; bool no_mask; int rem; @@ -448,8 +468,20 @@ ethnl_update_bitset32_verbose(u32 *bitmap, unsigned int nbits, } no_mask = tb[ETHTOOL_A_BITSET_NOMASK]; - if (no_mask) - ethnl_bitmap32_clear(bitmap, 0, nbits, mod); + if (no_mask) { + unsigned int nwords = DIV_ROUND_UP(nbits, 32); + unsigned int nbytes = nwords * sizeof(u32); + bool dummy; + + /* The bitmap size is only the size of the map part without + * its mask part. + */ + saved_bitmap = kcalloc(nwords, sizeof(u32), GFP_KERNEL); + if (!saved_bitmap) + return -ENOMEM; + memcpy(saved_bitmap, bitmap, nbytes); + ethnl_bitmap32_clear(bitmap, 0, nbits, &dummy); + } nla_for_each_nested(bit_attr, tb[ETHTOOL_A_BITSET_BITS], rem) { bool old_val, new_val; @@ -458,22 +490,30 @@ ethnl_update_bitset32_verbose(u32 *bitmap, unsigned int nbits, if (nla_type(bit_attr) != ETHTOOL_A_BITSET_BITS_BIT) { NL_SET_ERR_MSG_ATTR(extack, bit_attr, "only ETHTOOL_A_BITSET_BITS_BIT allowed in ETHTOOL_A_BITSET_BITS"); + kfree(saved_bitmap); return -EINVAL; } ret = ethnl_parse_bit(&idx, &new_val, nbits, bit_attr, no_mask, names, extack); - if (ret < 0) + if (ret < 0) { + kfree(saved_bitmap); return ret; + } old_val = bitmap[idx / 32] & ((u32)1 << (idx % 32)); if (new_val != old_val) { if (new_val) bitmap[idx / 32] |= ((u32)1 << (idx % 32)); else bitmap[idx / 32] &= ~((u32)1 << (idx % 32)); - *mod = true; + if (!no_mask) + *mod = true; } } + if (no_mask && !ethnl_bitmap32_equal(saved_bitmap, bitmap, nbits)) + *mod = true; + + kfree(saved_bitmap); return 0; } |