linux/include
Ido Schimmel ad4a3ca6a8 ipv4: ip_tunnel: Fix suspicious RCU usage warning in ip_tunnel_init_flow()
There are code paths from which the function is called without holding
the RCU read lock, resulting in a suspicious RCU usage warning [1].

Fix by using l3mdev_master_upper_ifindex_by_index() which will acquire
the RCU read lock before calling
l3mdev_master_upper_ifindex_by_index_rcu().

[1]
WARNING: suspicious RCU usage
6.12.0-rc3-custom-gac8f72681cf2 #141 Not tainted
-----------------------------
net/core/dev.c:876 RCU-list traversed in non-reader section!!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by ip/361:
 #0: ffffffff86fc7cb0 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x377/0xf60

stack backtrace:
CPU: 3 UID: 0 PID: 361 Comm: ip Not tainted 6.12.0-rc3-custom-gac8f72681cf2 #141
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
 <TASK>
 dump_stack_lvl+0xba/0x110
 lockdep_rcu_suspicious.cold+0x4f/0xd6
 dev_get_by_index_rcu+0x1d3/0x210
 l3mdev_master_upper_ifindex_by_index_rcu+0x2b/0xf0
 ip_tunnel_bind_dev+0x72f/0xa00
 ip_tunnel_newlink+0x368/0x7a0
 ipgre_newlink+0x14c/0x170
 __rtnl_newlink+0x1173/0x19c0
 rtnl_newlink+0x6c/0xa0
 rtnetlink_rcv_msg+0x3cc/0xf60
 netlink_rcv_skb+0x171/0x450
 netlink_unicast+0x539/0x7f0
 netlink_sendmsg+0x8c1/0xd80
 ____sys_sendmsg+0x8f9/0xc20
 ___sys_sendmsg+0x197/0x1e0
 __sys_sendmsg+0x122/0x1f0
 do_syscall_64+0xbb/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: db53cd3d88 ("net: Handle l3mdev in ip_tunnel_init_flow")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20241022063822.462057-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-29 11:12:25 -07:00
..
acpi Power management updates for 6.12-rc1 2024-09-16 07:47:50 +02:00
asm-generic move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
clocksource
crypto move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
cxl
drm Short summary of fixes pull: 2024-10-01 08:15:55 +10:00
dt-bindings soc: convert ep93xx to devicetree 2024-09-26 12:00:25 -07:00
keys KEYS: Remove unused declarations 2024-09-20 18:28:26 +03:00
kunit The core clk framework is left largely untouched this time around except for 2024-09-23 15:01:48 -07:00
kvm
linux Including fixes from netfiler, xfrm and bluetooth. 2024-10-24 16:43:50 -07:00
math-emu
media
memory
misc
net ipv4: ip_tunnel: Fix suspicious RCU usage warning in ip_tunnel_init_flow() 2024-10-29 11:12:25 -07:00
pcmcia
ras
rdma move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
rv
scsi move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
soc soc: driver updates for 6.12 2024-09-17 10:48:09 +02:00
sound ALSA: hda: fix trigger_tstamp_latched 2024-10-02 12:50:24 +02:00
target move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
trace vfs-6.12-rc5.fixes 2024-10-21 10:48:24 -07:00
uapi BPF fixes: 2024-10-18 16:27:14 -07:00
ufs Many singleton patches - please see the various changelogs for details. 2024-09-21 08:20:50 -07:00
vdso
video
xen xen: Remove dependency between pciback and privcmd 2024-10-18 11:59:04 +02:00