From: Taehee Yoo ap420073@gmail.com
commit 04b69426d846cd04ca9acefff1ea39e1c64d2714 upstream.
hsr slave interfaces don't have debugfs directory. So, hsr_debugfs_rename() shouldn't be called when hsr slave interface name is changed.
Test commands: ip link add dummy0 type dummy ip link add dummy1 type dummy ip link add hsr0 type hsr slave1 dummy0 slave2 dummy1 ip link set dummy0 name ap
Splat looks like: [21071.899367][T22666] ap: renamed from dummy0 [21071.914005][T22666] ================================================================== [21071.919008][T22666] BUG: KASAN: slab-out-of-bounds in hsr_debugfs_rename+0xaa/0xb0 [hsr] [21071.923640][T22666] Read of size 8 at addr ffff88805febcd98 by task ip/22666 [21071.926941][T22666] [21071.927750][T22666] CPU: 0 PID: 22666 Comm: ip Not tainted 5.5.0-rc2+ #240 [21071.929919][T22666] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [21071.935094][T22666] Call Trace: [21071.935867][T22666] dump_stack+0x96/0xdb [21071.936687][T22666] ? hsr_debugfs_rename+0xaa/0xb0 [hsr] [21071.937774][T22666] print_address_description.constprop.5+0x1be/0x360 [21071.939019][T22666] ? hsr_debugfs_rename+0xaa/0xb0 [hsr] [21071.940081][T22666] ? hsr_debugfs_rename+0xaa/0xb0 [hsr] [21071.940949][T22666] __kasan_report+0x12a/0x16f [21071.941758][T22666] ? hsr_debugfs_rename+0xaa/0xb0 [hsr] [21071.942674][T22666] kasan_report+0xe/0x20 [21071.943325][T22666] hsr_debugfs_rename+0xaa/0xb0 [hsr] [21071.944187][T22666] hsr_netdev_notify+0x1fe/0x9b0 [hsr] [21071.945052][T22666] ? __module_text_address+0x13/0x140 [21071.945897][T22666] notifier_call_chain+0x90/0x160 [21071.946743][T22666] dev_change_name+0x419/0x840 [21071.947496][T22666] ? __read_once_size_nocheck.constprop.6+0x10/0x10 [21071.948600][T22666] ? netdev_adjacent_rename_links+0x280/0x280 [21071.949577][T22666] ? __read_once_size_nocheck.constprop.6+0x10/0x10 [21071.950672][T22666] ? lock_downgrade+0x6e0/0x6e0 [21071.951345][T22666] ? do_setlink+0x811/0x2ef0 [21071.951991][T22666] do_setlink+0x811/0x2ef0 [21071.952613][T22666] ? is_bpf_text_address+0x81/0xe0 [ ... ]
Reported-by: syzbot+9328206518f08318a5fd@syzkaller.appspotmail.com Fixes: 4c2d5e33dcd3 ("hsr: rename debugfs file when interface name is changed") Signed-off-by: Taehee Yoo ap420073@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/hsr/hsr_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/hsr/hsr_main.c +++ b/net/hsr/hsr_main.c @@ -46,7 +46,8 @@ static int hsr_netdev_notify(struct noti hsr_check_carrier_and_operstate(hsr); break; case NETDEV_CHANGENAME: - hsr_debugfs_rename(dev); + if (is_hsr_master(dev)) + hsr_debugfs_rename(dev); break; case NETDEV_CHANGEADDR: if (port->type == HSR_PT_MASTER) {