Re: [PATCH] x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task

2020-08-15 Thread Eric Dumazet
On Sat, Aug 15, 2020 at 4:48 AM Ingo Molnar wrote: > > > * Eric Dumazet wrote: > > > syzbot found its way in 86_fsgsbase_read_task() [1] > > > > Fix is to make sure ldt pointer is not NULL. > > Thanks for this fix. Linus has picked it up (inclusive the typos to > the x86_fsgsbase_read_task()

Re: [PATCH] x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task

2020-08-15 Thread Ingo Molnar
* Eric Dumazet wrote: > syzbot found its way in 86_fsgsbase_read_task() [1] > > Fix is to make sure ldt pointer is not NULL. Thanks for this fix. Linus has picked it up (inclusive the typos to the x86_fsgsbase_read_task() function name ;-), it's now upstream under: 8ab49526b53d:

Re: [PATCH] x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task

2020-08-14 Thread Jann Horn
On Fri, Aug 14, 2020 at 9:03 PM Andy Lutomirski wrote: > > On Aug 14, 2020, at 11:16 AM, Eric Dumazet wrote: > > > > syzbot found its way in 86_fsgsbase_read_task() [1] > > > > Fix is to make sure ldt pointer is not NULL > > Acked-by: Andy Lutomirski > > Maybe add something like this to the

Re: [PATCH] x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task

2020-08-14 Thread Eric Dumazet
On Fri, Aug 14, 2020 at 12:03 PM Andy Lutomirski wrote: > > > > > On Aug 14, 2020, at 11:16 AM, Eric Dumazet wrote: > > > > syzbot found its way in 86_fsgsbase_read_task() [1] > > > > Fix is to make sure ldt pointer is not NULL > > Acked-by: Andy Lutomirski > > Maybe add something like this to

Re: [PATCH] x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task

2020-08-14 Thread Andy Lutomirski
> On Aug 14, 2020, at 11:16 AM, Eric Dumazet wrote: > > syzbot found its way in 86_fsgsbase_read_task() [1] > > Fix is to make sure ldt pointer is not NULL Acked-by: Andy Lutomirski Maybe add something like this to the changelog: This can happen if ptrace() or sigreturn() pokes an LDT

[PATCH] x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task

2020-08-14 Thread Eric Dumazet
syzbot found its way in 86_fsgsbase_read_task() [1] Fix is to make sure ldt pointer is not NULL. [1] general protection fault, probably for non-canonical address 0xdc01: [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0008-0x000f] CPU: 0 PID: