linux/net/core
Willem de Bruijn f72c4ac695 skbuff: in skb_copy_ubufs unclone before releasing zerocopy
skb_copy_ubufs must unclone before it is safe to modify its
skb_shared_info with skb_zcopy_clear.

Commit b90ddd5687 ("skbuff: skb_copy_ubufs must release uarg even
without user frags") ensures that all skbs release their zerocopy
state, even those without frags.

But I forgot an edge case where such an skb arrives that is cloned.

The stack does not build such packets. Vhost/tun skbs have their
frags orphaned before cloning. TCP skbs only attach zerocopy state
when a frag is added.

But if TCP packets can be trimmed or linearized, this might occur.
Tracing the code I found no instance so far (e.g., skb_linearize
ends up calling skb_zcopy_clear if !skb->data_len).

Still, it is non-obvious that no path exists. And it is fragile to
rely on this.

Fixes: b90ddd5687 ("skbuff: skb_copy_ubufs must release uarg even without user frags")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-28 14:26:22 -05:00
..
datagram.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-04 09:26:51 +09:00
dev_addr_lists.c
dev_ioctl.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dev.c xdp: linearize skb in netif_receive_generic_xdp() 2017-12-15 14:34:36 +01:00
devlink.c devlink: Add IPv6 header for dpipe 2017-08-31 14:42:19 -07:00
drop_monitor.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
dst_cache.c net: dst_cache_per_cpu_dst_set() can be static 2016-03-18 17:45:08 -04:00
dst.c net: dst: move cpu inside ifdef to avoid compilation warning 2017-10-10 15:55:58 -07:00
ethtool.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-22 13:39:14 +01:00
fib_notifier.c net: Protect iterations over net::fib_notifier_ops in fib_seq_sum() 2017-11-15 14:01:30 +09:00
fib_rules.c fib_rules: exit_net cleanup check added 2017-11-14 15:45:53 +09:00
filter.c bpf: introduce ARG_PTR_TO_MEM_OR_NULL 2017-11-22 21:40:54 +01:00
flow_dissector.c tipc: improve link resiliency when rps is activated 2017-11-11 15:36:05 +09:00
gen_estimator.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
gen_stats.c net_sched: gen_estimator: complete rewrite of rate estimators 2016-12-05 15:21:59 -05:00
gro_cells.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hwbm.c net: hwbm: Fix unbalanced spinlock in error case 2016-05-25 12:35:09 -07:00
link_watch.c
lwt_bpf.c bpf: rename bpf_compute_data_end into bpf_compute_data_pointers 2017-09-26 13:36:44 -07:00
lwtunnel.c ipv6: sr: define core operations for seg6local lightweight tunnel 2017-08-07 14:16:22 -07:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
neighbour.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
net_namespace.c net: Fix double free and memory corruption in get_net_ns_by_id() 2017-12-20 12:42:22 -05:00
net-procfs.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
net-sysfs.c net-sysfs: trigger netlink notification on ifalias change via sysfs 2017-11-14 22:03:21 +09:00
net-sysfs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
net-traces.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-04 09:26:51 +09:00
netclassid_cgroup.c cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS 2017-07-21 11:14:51 -04:00
netevent.c
netpoll.c netpoll: Use lockdep to assert IRQs are disabled/enabled 2017-11-08 11:13:54 +01:00
netprio_cgroup.c net: remove duplicate includes 2017-12-13 13:18:46 -05:00
pktgen.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-11-15 11:56:19 -08:00
ptp_classifier.c ptp: Change ptp_class to a proper bitmask 2015-11-03 11:08:22 -05:00
request_sock.c ipv4: Namespaceify tcp_max_syn_backlog knob 2016-12-29 11:38:31 -05:00
rtnetlink.c rtnetlink: fix missing size for IFLA_IF_NETNSID 2017-11-08 13:46:25 +09:00
scm.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h> 2017-03-02 08:42:29 +01:00
secure_seq.c tcp: Namespaceify sysctl_tcp_timestamps 2017-06-08 10:53:29 -04:00
skbuff.c skbuff: in skb_copy_ubufs unclone before releasing zerocopy 2017-12-28 14:26:22 -05:00
sock_diag.c netlink: extended ACK reporting 2017-04-13 13:58:20 -04:00
sock_reuseport.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sock.c Merge branch 'akpm' (patches from Andrew) 2017-11-15 19:42:40 -08:00
stream.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sysctl_net_core.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
timestamping.c
tso.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
utils.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00