From b502b3185cd68f24510f8a253bf31a1b34605bb6 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 4 Nov 2022 12:13:40 -0700 Subject: [PATCH] genetlink: use iterator in the op to policy map dumping We can't put the full iterator in the struct ctrl_dump_policy_ctx because dump context is statically sized by netlink core. Allocate it dynamically. Rename policy to dump_map to make the logic a little easier to follow. Signed-off-by: Jakub Kicinski Reviewed-by: Jacob Keller Signed-off-by: David S. Miller --- net/netlink/genetlink.c | 49 ++++++++++++++++++++++++++----------------------- 1 file changed, 26 insertions(+), 23 deletions(-) diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 06bf091..4b8c65d 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -1252,10 +1252,10 @@ static int genl_ctrl_event(int event, const struct genl_family *family, struct ctrl_dump_policy_ctx { struct netlink_policy_dump_state *state; const struct genl_family *rt; - unsigned int opidx; + struct genl_op_iter *op_iter; u32 op; u16 fam_id; - u8 policies:1, + u8 dump_map:1, single_op:1; }; @@ -1325,9 +1325,16 @@ static int ctrl_dumppolicy_start(struct netlink_callback *cb) if (!ctx->state) return -ENODATA; + + ctx->dump_map = 1; return 0; } + ctx->op_iter = kmalloc(sizeof(*ctx->op_iter), GFP_KERNEL); + if (!ctx->op_iter) + return -ENOMEM; + ctx->dump_map = genl_op_iter_init(rt, ctx->op_iter); + for (genl_op_iter_init(rt, &i); genl_op_iter_next(&i); ) { if (i.doit.policy) { err = netlink_policy_dump_add_policy(&ctx->state, @@ -1345,12 +1352,16 @@ static int ctrl_dumppolicy_start(struct netlink_callback *cb) } } - if (!ctx->state) - return -ENODATA; + if (!ctx->state) { + err = -ENODATA; + goto err_free_op_iter; + } return 0; err_free_state: netlink_policy_dump_free(ctx->state); +err_free_op_iter: + kfree(ctx->op_iter); return err; } @@ -1430,11 +1441,10 @@ static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx; void *hdr; - if (!ctx->policies) { - struct genl_split_ops doit, dumpit; - struct genl_ops op; - + if (ctx->dump_map) { if (ctx->single_op) { + struct genl_split_ops doit, dumpit; + if (genl_get_cmd(ctx->op, GENL_CMD_CAP_DO, ctx->rt, &doit) && genl_get_cmd(ctx->op, GENL_CMD_CAP_DUMP, @@ -1446,26 +1456,18 @@ static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) if (ctrl_dumppolicy_put_op(skb, cb, &doit, &dumpit)) return skb->len; - /* don't enter the loop below */ - ctx->opidx = genl_get_cmd_cnt(ctx->rt); + /* done with the per-op policy index list */ + ctx->dump_map = 0; } - while (ctx->opidx < genl_get_cmd_cnt(ctx->rt)) { - genl_get_cmd_by_index(ctx->opidx, ctx->rt, &op); - - genl_cmd_full_to_split(&doit, ctx->rt, - &op, GENL_CMD_CAP_DO); - genl_cmd_full_to_split(&dumpit, ctx->rt, - &op, GENL_CMD_CAP_DUMP); - - if (ctrl_dumppolicy_put_op(skb, cb, &doit, &dumpit)) + while (ctx->dump_map) { + if (ctrl_dumppolicy_put_op(skb, cb, + &ctx->op_iter->doit, + &ctx->op_iter->dumpit)) return skb->len; - ctx->opidx++; + ctx->dump_map = genl_op_iter_next(ctx->op_iter); } - - /* completed with the per-op policy index list */ - ctx->policies = true; } while (netlink_policy_dump_loop(ctx->state)) { @@ -1498,6 +1500,7 @@ static int ctrl_dumppolicy_done(struct netlink_callback *cb) { struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx; + kfree(ctx->op_iter); netlink_policy_dump_free(ctx->state); return 0; } -- 2.7.4