github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-03 03:53:37 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

tun: Keep hdr_len in tun_get_user()

Browse Source 
hdr_len is repeatedly used so keep it in a local variable.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250207-tun-v6-2-fb49cf8b103e@daynix.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Akihiko Odaki 2025-02-07 15:10:52 +09:00 committed by Jakub Kicinski
parent 5a9c5e5d8a
commit 07e8b3bae2
1 changed files with 11 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
drivers/net/tun.c
View File

@ -1747,6 +1747,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
struct virtio_net_hdr gso = { 0 };
int good_linear;
int copylen;
int hdr_len = 0;
bool zerocopy = false;
int err;
u32 rxhash = 0;
@ -1773,19 +1774,21 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
if (!copy_from_iter_full(&gso, sizeof(gso), from))
return -EFAULT;
if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
tun16_to_cpu(tun, gso.csum_start) + tun16_to_cpu(tun, gso.csum_offset) + 2 > tun16_to_cpu(tun, gso.hdr_len))
gso.hdr_len = cpu_to_tun16(tun, tun16_to_cpu(tun, gso.csum_start) + tun16_to_cpu(tun, gso.csum_offset) + 2);
hdr_len = tun16_to_cpu(tun, gso.hdr_len);
if (tun16_to_cpu(tun, gso.hdr_len) > len)
if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
hdr_len = max(tun16_to_cpu(tun, gso.csum_start) + tun16_to_cpu(tun, gso.csum_offset) + 2, hdr_len);
gso.hdr_len = cpu_to_tun16(tun, hdr_len);
}
if (hdr_len > len)
return -EINVAL;
iov_iter_advance(from, vnet_hdr_sz - sizeof(gso));
}
if ((tun->flags & TUN_TYPE_MASK) == IFF_TAP) {
align += NET_IP_ALIGN;
if (unlikely(len < ETH_HLEN ||
(gso.hdr_len && tun16_to_cpu(tun, gso.hdr_len) < ETH_HLEN)))
if (unlikely(len < ETH_HLEN || (hdr_len && hdr_len < ETH_HLEN)))
return -EINVAL;
}
@ -1798,9 +1801,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
* enough room for skb expand head in case it is used.
* The rest of the buffer is mapped from userspace.
*/
copylen = gso.hdr_len ? tun16_to_cpu(tun, gso.hdr_len) : GOODCOPY_LEN;
if (copylen > good_linear)
copylen = good_linear;
copylen = min(hdr_len ? hdr_len : GOODCOPY_LEN, good_linear);
linear = copylen;
iov_iter_advance(&i, copylen);
if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS)
@ -1821,10 +1822,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
} else {
if (!zerocopy) {
copylen = len;
if (tun16_to_cpu(tun, gso.hdr_len) > good_linear)
linear = good_linear;
else
linear = tun16_to_cpu(tun, gso.hdr_len);
linear = min(hdr_len, good_linear);
}
if (frags) {