Hi,

On Tue, 27 Aug 2024 13:25:52 +0800
Pengfei Xu [off-list ref] wrote:

Hi Maxime Chevallier,

I used syzkaller and found that: there was general protection fault in
phy_start_cable_test_tdr in Linux next:next-20240826.

Bisected and found first bad commit:
"
3688ff3077d3 net: ethtool: cable-test: Target the command to the requested PHY
"
After reverted below commit on top of next-20240826, this issue was gone.

All detailed info: https://github.com/xupengfe/syzkaller_logs/tree/main/240826_202302_phy_start_cable_test_tdr
Syzkaller repro code: https://github.com/xupengfe/syzkaller_logs/blob/main/240826_202302_phy_start_cable_test_tdr/repro.c
Syzkaller repro syscall steps: https://github.com/xupengfe/syzkaller_logs/blob/main/240826_202302_phy_start_cable_test_tdr/repro.prog
Syzkaller report: https://github.com/xupengfe/syzkaller_logs/blob/main/240826_202302_phy_start_cable_test_tdr/repro.report
Kconfig(make olddefconfig): https://github.com/xupengfe/syzkaller_logs/blob/main/240826_202302_phy_start_cable_test_tdr/kconfig_origin
Bisect info: https://github.com/xupengfe/syzkaller_logs/blob/main/240826_202302_phy_start_cable_test_tdr/bisect_info.log
bzImage: https://github.com/xupengfe/syzkaller_logs/raw/main/240826_202302_phy_start_cable_test_tdr/bzImage_1ca4237ad9ce29b0c66fe87862f1da54ac56a1e8.tar.gz
Issue dmesg: https://github.com/xupengfe/syzkaller_logs/blob/main/240826_202302_phy_start_cable_test_tdr/1ca4237ad9ce29b0c66fe87862f1da54ac56a1e8_dmesg.log

Thanks for the report !

This issue has indeed been detected, and is being addressed, see :

https://lore.kernel.org/netdev/20240826134656.94892-1-djahchankoike@gmail.com/ (local)

Thanks,

Maxime