Some drivers clear the 'ethtool_link_ksettings' struct in their
get_link_ksettings() callback, before populating it with actual values.
Such drivers will set the new 'link_mode' field to zero, resulting in
user space receiving wrong link mode information given that zero is a
valid value for the field.
Another problem is that some drivers (notably tun) can report random
values in the 'link_mode' field. This can result in a general protection
fault when the field is used as an index to the 'link_mode_params' array
[1].
This happens because such drivers implement their set_link_ksettings()
callback by simply overwriting their private copy of
'ethtool_link_ksettings' struct with the one they get from the stack,
which is not always properly initialized.
Fix these problems by removing 'link_mode' from 'ethtool_link_ksettings'
and instead have drivers call ethtool_params_from_link_mode() with the
current link mode. The function will derive the link parameters (e.g.,
speed) from the link mode and fill them in the 'ethtool_link_ksettings'
struct.
v3:
* Remove link_mode parameter and derive the link parameters in
the driver instead of passing link_mode parameter to ethtool
and derive it there.
v2:
* Introduce 'cap_link_mode_supported' instead of adding a
validity field to 'ethtool_link_ksettings' struct.
[1]
general protection fault, probably for non-canonical address 0xdffffc00f14cc32c: 0000 [#1] PREEMPT SMP KASAN
KASAN: probably user-memory-access in range [0x000000078a661960-0x000000078a661967]
CPU: 0 PID: 8452 Comm: syz-executor360 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__ethtool_get_link_ksettings+0x1a3/0x3a0 net/ethtool/ioctl.c:446
Code: b7 3e fa 83 fd ff 0f 84 30 01 00 00 e8 16 b0 3e fa 48 8d 3c ed 60 d5 69 8a 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03
+38 d0 7c 08 84 d2 0f 85 b9
RSP: 0018:
ffffc900019df7a0 EFLAGS:
00010202
RAX:
dffffc0000000000 RBX:
ffff888026136008 RCX:
0000000000000000
RDX:
00000000f14cc32c RSI:
ffffffff873439ca RDI:
000000078a661960
RBP:
00000000ffff8880 R08:
00000000ffffffff R09:
ffff88802613606f
R10:
ffffffff873439bc R11:
0000000000000000 R12:
0000000000000000
R13:
ffff88802613606c R14:
ffff888011d0c210 R15:
ffff888011d0c210
FS:
0000000000749300(0000) GS:
ffff8880b9c00000(0000) knlGS:
0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
CR2:
00000000004b60f0 CR3:
00000000185c2000 CR4:
00000000001506f0
DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
DR3:
0000000000000000 DR6:
00000000fffe0ff0 DR7:
0000000000000400
Call Trace:
linkinfo_prepare_data+0xfd/0x280 net/ethtool/linkinfo.c:37
ethnl_default_notify+0x1dc/0x630 net/ethtool/netlink.c:586
ethtool_notify+0xbd/0x1f0 net/ethtool/netlink.c:656
ethtool_set_link_ksettings+0x277/0x330 net/ethtool/ioctl.c:620
dev_ethtool+0x2b35/0x45d0 net/ethtool/ioctl.c:2842
dev_ioctl+0x463/0xb70 net/core/dev_ioctl.c:440
sock_do_ioctl+0x148/0x2d0 net/socket.c:1060
sock_ioctl+0x477/0x6a0 net/socket.c:1177
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: c8907043c6ac9 ("ethtool: Get link mode in use instead of speed and duplex parameters")
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
u32 ptys_eth_proto,
struct ethtool_link_ksettings *cmd)
{
+ struct mlxsw_sp1_port_link_mode link;
int i;
- cmd->link_mode = -1;
+ cmd->base.speed = SPEED_UNKNOWN;
+ cmd->base.duplex = DUPLEX_UNKNOWN;
+ cmd->lanes = 0;
if (!carrier_ok)
return;
for (i = 0; i < MLXSW_SP1_PORT_LINK_MODE_LEN; i++) {
- if (ptys_eth_proto & mlxsw_sp1_port_link_mode[i].mask)
- cmd->link_mode = mlxsw_sp1_port_link_mode[i].mask_ethtool;
+ if (ptys_eth_proto & mlxsw_sp1_port_link_mode[i].mask) {
+ link = mlxsw_sp1_port_link_mode[i];
+ ethtool_params_from_link_mode(cmd,
+ link.mask_ethtool);
+ }
}
}
struct mlxsw_sp2_port_link_mode link;
int i;
- cmd->link_mode = -1;
+ cmd->base.speed = SPEED_UNKNOWN;
+ cmd->base.duplex = DUPLEX_UNKNOWN;
+ cmd->lanes = 0;
if (!carrier_ok)
return;
for (i = 0; i < MLXSW_SP2_PORT_LINK_MODE_LEN; i++) {
if (ptys_eth_proto & mlxsw_sp2_port_link_mode[i].mask) {
link = mlxsw_sp2_port_link_mode[i];
- cmd->link_mode = link.mask_ethtool[1];
+ ethtool_params_from_link_mode(cmd,
+ link.mask_ethtool[1]);
}
}
}
__ETHTOOL_DECLARE_LINK_MODE_MASK(lp_advertising);
} link_modes;
u32 lanes;
- enum ethtool_link_mode_bit_indices link_mode;
};
/**
*/
void ethtool_set_ethtool_phy_ops(const struct ethtool_phy_ops *ops);
+/*
+ * ethtool_params_from_link_mode - Derive link parameters from a given link mode
+ * @link_ksettings: Link parameters to be derived from the link mode
+ * @link_mode: Link mode
+ */
+void
+ethtool_params_from_link_mode(struct ethtool_link_ksettings *link_ksettings,
+ enum ethtool_link_mode_bit_indices link_mode);
#endif /* _LINUX_ETHTOOL_H */
rtnl_unlock();
}
EXPORT_SYMBOL_GPL(ethtool_set_ethtool_phy_ops);
+
+void
+ethtool_params_from_link_mode(struct ethtool_link_ksettings *link_ksettings,
+ enum ethtool_link_mode_bit_indices link_mode)
+{
+ const struct link_mode_info *link_info;
+
+ if (WARN_ON_ONCE(link_mode >= __ETHTOOL_LINK_MODE_MASK_NBITS))
+ return;
+
+ link_info = &link_mode_params[link_mode];
+ link_ksettings->base.speed = link_info->speed;
+ link_ksettings->lanes = link_info->lanes;
+ link_ksettings->base.duplex = link_info->duplex;
+}
+EXPORT_SYMBOL_GPL(ethtool_params_from_link_mode);
int __ethtool_get_link_ksettings(struct net_device *dev,
struct ethtool_link_ksettings *link_ksettings)
{
- const struct link_mode_info *link_info;
- int err;
-
ASSERT_RTNL();
if (!dev->ethtool_ops->get_link_ksettings)
return -EOPNOTSUPP;
memset(link_ksettings, 0, sizeof(*link_ksettings));
-
- link_ksettings->link_mode = -1;
- err = dev->ethtool_ops->get_link_ksettings(dev, link_ksettings);
- if (err)
- return err;
-
- if (link_ksettings->link_mode != -1) {
- link_info = &link_mode_params[link_ksettings->link_mode];
- link_ksettings->base.speed = link_info->speed;
- link_ksettings->lanes = link_info->lanes;
- link_ksettings->base.duplex = link_info->duplex;
- }
-
- return 0;
+ return dev->ethtool_ops->get_link_ksettings(dev, link_ksettings);
}
EXPORT_SYMBOL(__ethtool_get_link_ksettings);
projects / kernel.git / commitdiff