[PATCH] ARC: fix CONFIG_HARDENED_USERCOPY

2021-06-09 Thread Vineet Gupta
Currently enabling this triggers a warning | usercopy: Kernel memory overwrite attempt detected to kernel text (offset 155633, size 11)! | usercopy: BUG: failure at mm/usercopy.c:99/usercopy_abort()! | |gcc generated __builtin_trap |Path: /bin/busybox |CPU: 0 PID: 84 Comm: init Not tainted 5.4.22

Re: [PATCH] ARC: fix CONFIG_HARDENED_USERCOPY

2021-06-10 Thread Kees Cook
On Wed, Jun 09, 2021 at 03:12:11PM -0700, Vineet Gupta wrote: > Currently enabling this triggers a warning > > | usercopy: Kernel memory overwrite attempt detected to kernel text (offset > 155633, size 11)! > | usercopy: BUG: failure at mm/usercopy.c:99/usercopy_abort()! > | > |gcc generated __bu

Re: [PATCH] ARC: fix CONFIG_HARDENED_USERCOPY

2021-06-10 Thread Vineet Gupta
On 6/10/21 10:02 AM, Kees Cook wrote: > On Wed, Jun 09, 2021 at 03:12:11PM -0700, Vineet Gupta wrote: >> Currently enabling this triggers a warning >> >> | usercopy: Kernel memory overwrite attempt detected to kernel text (offset >> 155633, size 11)! >> | usercopy: BUG: failure at mm/usercopy.c:99

Re: [PATCH] ARC: fix CONFIG_HARDENED_USERCOPY

2021-06-10 Thread Kees Cook
On Thu, Jun 10, 2021 at 06:56:48PM +, Vineet Gupta wrote: > On 6/10/21 10:02 AM, Kees Cook wrote: > > On Wed, Jun 09, 2021 at 03:12:11PM -0700, Vineet Gupta wrote: > >> Currently enabling this triggers a warning > >> > >> | usercopy: Kernel memory overwrite attempt detected to kernel text > >>

Re: [PATCH] ARC: fix CONFIG_HARDENED_USERCOPY

2021-06-10 Thread Vineet Gupta
On 6/10/21 4:56 PM, Kees Cook wrote: |Stack Trace: | memfd_fcntl+0x0/0x470 | usercopy_abort+0x8a/0x8c | __check_object_size+0x10e/0x138 | copy_strings+0x1f4/0x38c | __do_execve_file+0x352/0x848 | EV_Trap+0xcc/0xd0 >>> What was the root cause here? Was it that the