Re: WARNING in do_notify_parent (kernel/signal.c:2174)

[Oleg Nesterov]

On 05/07, y2k wrote:
>
> 7.1.0-rc2-00099-gadc1e5c6203c
> arch: x86_64
> preemption: PREEMPT(lazy)
>
>
> REPRODUCER (syzkaller program)
> ------------------------------
> # {Threaded:false Repeat:false Procs:1 Sandbox: SandboxArg:0 Sysctl:true HandleSegv:true}
> syz_clone(0x200080, &(0x7f00000003c0)="9562597ade4c359303b4585229dfcf8a12e5a172b6bfeb0d6d973e21df1c19605d9eb45142bd770cb6310057f646adcbde17681e392e8c11af0836a4ffff47c8c083fd4da4af3fdaa71e8a42df556d90bfb7e2511aac2628e271cddf224733c2881a422684cd3c7033fd24e00b205efdd94ece24e22040e80a310fb8cfaafecb00e067c5c2dfc13181c8773d3a37aa7635b8da5dbf2c9b25a7192f3861c442929542a4a564920eb870a06b383e781fe0d54d05275c7e2cd2f901c72c8270308a5db0adbed89176bac1122b21cb2e2d202569ae8d5a97cbce75aff3444207cb68bfcf", 0xe2, 0x0, 0x0, 0x0)
...

> WARNING: kernel/signal.c:2174 at do_notify_parent+0xfef/0x11c0 kernel/signal.c:2174

...

> Follow-up: I found that commit 0f8e38eeb995 by Oleg Nesterov
> ("do_notify_parent: sanitize the valid_signal() checks") appears to be
> related to this WARNING.

>From the changelog:

	Now that kernel_clone() checks valid_signal(args->exit_signal), the "sig"
	argument of do_notify_parent() must always be valid or we have a bug.

This patch depends on

	[PATCH v3] kernel/fork: validate exit_signal in kernel_clone()
	https://lore.kernel.org/all/20260316151956.563558-1-kartikey406@xxxxxxxxx/

Was kernel-fork-validate-exit_signal-in-kernel_clone.patch in mm-tree

So it seems that my patch is already merged, but the patch from Deepanshu is not...

Oleg.