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author | Danielle Ratson <danieller@nvidia.com> | 2021-04-07 13:06:51 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2021-04-07 14:53:04 -0700 |
commit | a975d7d8a356ce92872af0b007b101183f0224e2 (patch) | |
tree | 170a5179057659b748c85dc2e39c080f5e70df61 /net/ethtool/common.c | |
parent | bb58023bee8b08c329c161c2f20b157db8a5ba96 (diff) | |
download | linux-stable-a975d7d8a356ce92872af0b007b101183f0224e2.tar.gz linux-stable-a975d7d8a356ce92872af0b007b101183f0224e2.tar.bz2 linux-stable-a975d7d8a356ce92872af0b007b101183f0224e2.zip |
ethtool: Remove link_mode param and derive link params from driver
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>
Diffstat (limited to 'net/ethtool/common.c')
-rw-r--r-- | net/ethtool/common.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/net/ethtool/common.c b/net/ethtool/common.c index c6a383dfd6c2..030aa7984a91 100644 --- a/net/ethtool/common.c +++ b/net/ethtool/common.c @@ -562,3 +562,19 @@ void ethtool_set_ethtool_phy_ops(const struct ethtool_phy_ops *ops) 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); |