bpf: sockmap, updating the sg structure should also update curr

Curr pointer should be updated when the sg structure is shifted.

Fixes: 7246d8ed4d ("bpf: helper to pop data from messages")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20231206232706.374377-3-john.fastabend@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
John Fastabend 2023-12-06 15:27:06 -08:00 committed by Jakub Kicinski
parent c5a595000e
commit bb9aefde5b
1 changed files with 19 additions and 0 deletions

View File

@ -2602,6 +2602,22 @@ BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes)
return 0;
}
static void sk_msg_reset_curr(struct sk_msg *msg)
{
u32 i = msg->sg.start;
u32 len = 0;
do {
len += sk_msg_elem(msg, i)->length;
sk_msg_iter_var_next(i);
if (len >= msg->sg.size)
break;
} while (i != msg->sg.end);
msg->sg.curr = i;
msg->sg.copybreak = 0;
}
static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
.func = bpf_msg_cork_bytes,
.gpl_only = false,
@ -2721,6 +2737,7 @@ BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start,
msg->sg.end - shift + NR_MSG_FRAG_IDS :
msg->sg.end - shift;
out:
sk_msg_reset_curr(msg);
msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset;
msg->data_end = msg->data + bytes;
return 0;
@ -2857,6 +2874,7 @@ BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
msg->sg.data[new] = rsge;
}
sk_msg_reset_curr(msg);
sk_msg_compute_data_pointers(msg);
return 0;
}
@ -3025,6 +3043,7 @@ BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start,
sk_mem_uncharge(msg->sk, len - pop);
msg->sg.size -= (len - pop);
sk_msg_reset_curr(msg);
sk_msg_compute_data_pointers(msg);
return 0;
}