If we do not have a master network device attached dst->cpu_dp will be
NULL and accessing cpu_dp->netdev will create a trace similar to the one
below. The correct check is on dst->cpu_dp period.
[ 1.004650] DSA: switch 0 0 parsed
[ 1.008078] Unable to handle kernel NULL pointer dereference at
virtual address 00000010
[ 1.016195] pgd = c0003000
[ 1.018918] [00000010] *pgd=80000000004003, *pmd=00000000
[ 1.024349] Internal error: Oops: 206 [#1] SMP ARM
[ 1.029157] Modules linked in:
[ 1.032228] CPU: 0 PID: 1 Comm: swapper/0 Not tainted
4.13.0-rc6-00071-g45b45afab9bd-dirty #7
[ 1.040772] Hardware name: Broadcom STB (Flattened Device Tree)
[ 1.046704] task: ee08f840 task.stack: ee090000
[ 1.051258] PC is at dsa_register_switch+0x5e0/0x9dc
[ 1.056234] LR is at dsa_register_switch+0x5d0/0x9dc
[ 1.061211] pc : [<c08fb28c>] lr : [<c08fb27c>] psr: 60000213
[ 1.067491] sp : ee091d88 ip : 00000000 fp : 0000000c
[ 1.072728] r10: 00000000 r9 : 00000001 r8 : ee208010
[ 1.077965] r7 : ee2b57b0 r6 : ee2b5780 r5 : 00000000 r4 :
ee208e0c
[ 1.084506] r3 : 00000000 r2 : 00040d00 r1 : 2d1b2000 r0 :
00000016
[ 1.091050] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM
Segment user
[ 1.098199] Control: 32c5387d Table: 00003000 DAC: fffffffd
[ 1.103957] Process swapper/0 (pid: 1, stack limit = 0xee090210)
Reported-by: Dan Carpenter <dan.carpen...@oracle.com>
Fixes: 6d3c8c0dd88a ("net: dsa: Remove master_netdev and use
dst->cpu_dp->netdev")
Signed-off-by: Florian Fainelli <f.faine...@gmail.com>
---
net/dsa/dsa2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index c442051d5a55..20bc9c56fca0 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -577,7 +577,7 @@ static int dsa_dst_parse(struct dsa_switch_tree *dst)
return err;
}
- if (!dst->cpu_dp->netdev) {
+ if (!dst->cpu_dp) {
pr_warn("Tree has no master device\n");
return -EINVAL;
}
--
1.9.1
