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40b1c813ba
A recent change added a null check on p->dev after p->dev was being
dereferenced by the ns_capable check on p->dev. It turns out that
neither the p->dev and p->br null checks are necessary, and can be
removed, which cleans up a static analyis warning.
As Nikolay Aleksandrov noted, these checks can be removed because:
"My reasoning of why it shouldn't be possible:
- On port add new_nbp() sets both p->dev and p->br before creating
kobj/sysfs
- On port del (trickier) del_nbp() calls kobject_del() before call_rcu()
to destroy the port which in turn calls sysfs_remove_dir() which uses
kernfs_remove() which deactivates (shouldn't be able to open new
files) and calls kernfs_drain() to drain current open/mmaped files in
the respective dir before continuing, thus making it impossible to
open a bridge port sysfs file with p->dev and p->br equal to NULL.
So I think it's safe to remove those checks altogether. It'd be nice to
get a second look over my reasoning as I might be missing something in
sysfs/kernfs call path."
Thanks to Nikolay Aleksandrov's suggestion to remove the check and
David Miller for sanity checking this.
Detected by CoverityScan, CID#751490 ("Dereference before null check")
Fixes:
|
||
|---|---|---|
| .. | ||
| netfilter | ||
| br.c | ||
| br_arp_nd_proxy.c | ||
| br_device.c | ||
| br_fdb.c | ||
| br_forward.c | ||
| br_if.c | ||
| br_input.c | ||
| br_ioctl.c | ||
| br_mdb.c | ||
| br_multicast.c | ||
| br_netfilter_hooks.c | ||
| br_netfilter_ipv6.c | ||
| br_netlink.c | ||
| br_netlink_tunnel.c | ||
| br_nf_core.c | ||
| br_private.h | ||
| br_private_stp.h | ||
| br_private_tunnel.h | ||
| br_stp.c | ||
| br_stp_bpdu.c | ||
| br_stp_if.c | ||
| br_stp_timer.c | ||
| br_switchdev.c | ||
| br_sysfs_br.c | ||
| br_sysfs_if.c | ||
| br_vlan.c | ||
| br_vlan_tunnel.c | ||
| Kconfig | ||
| Makefile | ||