Mike Christie
2023-Mar-21 17:46 UTC
[syzbot] [kernel?] general protection fault in vhost_task_start
On 3/21/23 12:03 PM, syzbot wrote:> RIP: 0010:vhost_task_start+0x22/0x40 kernel/vhost_task.c:115 > Code: 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 53 48 89 fb e8 c3 67 2c 00 48 8d 7b 70 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 0a 48 8b 7b 70 5b e9 fe bd 02 00 e8 79 ec 7e 00 eb > RSP: 0018:ffffc90003a9fc38 EFLAGS: 00010207 > RAX: dffffc0000000000 RBX: fffffffffffffff4 RCX: 0000000000000000 > RDX: 000000000000000c RSI: ffffffff81564c8d RDI: 0000000000000064 > RBP: ffff88802b21dd40 R08: 0000000000000100 R09: ffffffff8c917cf3 > R10: 00000000fffffff4 R11: 0000000000000000 R12: fffffffffffffff4 > R13: ffff888075d000b0 R14: ffff888075d00000 R15: ffff888075d00008 > FS: 0000555556247300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007ffe3d8e5ff8 CR3: 00000000215d4000 CR4: 00000000003506f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > vhost_worker_create drivers/vhost/vhost.c:580 [inline]The return value from vhost_task_create is incorrect if the kzalloc fails. Christian, here is a fix for what's in your tree. Do you want me to submit a follow up patch like this or a replacement patch for: commit 77feab3c4156 ("vhost_task: Allow vhost layer to use copy_process") with the fix rolled into it?>From 0677ad6d77722f301ca35e8e0f8fd0cbd5ed8484 Mon Sep 17 00:00:00 2001From: Mike Christie <michael.christie at oracle.com> Date: Tue, 21 Mar 2023 12:39:39 -0500 Subject: [PATCH] vhost_task: Fix vhost_task_create return value vhost_task_create is supposed to return the vhost_task or NULL on failure. This fixes it to return the correct value when the allocation of the struct fails. --- kernel/vhost_task.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/vhost_task.c b/kernel/vhost_task.c index 4b8aff160640..b7cbd66f889e 100644 --- a/kernel/vhost_task.c +++ b/kernel/vhost_task.c @@ -88,7 +88,7 @@ struct vhost_task *vhost_task_create(int (*fn)(void *), void *arg, vtsk = kzalloc(sizeof(*vtsk), GFP_KERNEL); if (!vtsk) - return ERR_PTR(-ENOMEM); + return NULL; init_completion(&vtsk->exited); vtsk->data = arg; vtsk->fn = fn;
Michael S. Tsirkin
2023-Mar-21 17:54 UTC
[syzbot] [kernel?] general protection fault in vhost_task_start
On Tue, Mar 21, 2023 at 12:46:04PM -0500, Mike Christie wrote:> On 3/21/23 12:03 PM, syzbot wrote: > > RIP: 0010:vhost_task_start+0x22/0x40 kernel/vhost_task.c:115 > > Code: 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 53 48 89 fb e8 c3 67 2c 00 48 8d 7b 70 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 0a 48 8b 7b 70 5b e9 fe bd 02 00 e8 79 ec 7e 00 eb > > RSP: 0018:ffffc90003a9fc38 EFLAGS: 00010207 > > RAX: dffffc0000000000 RBX: fffffffffffffff4 RCX: 0000000000000000 > > RDX: 000000000000000c RSI: ffffffff81564c8d RDI: 0000000000000064 > > RBP: ffff88802b21dd40 R08: 0000000000000100 R09: ffffffff8c917cf3 > > R10: 00000000fffffff4 R11: 0000000000000000 R12: fffffffffffffff4 > > R13: ffff888075d000b0 R14: ffff888075d00000 R15: ffff888075d00008 > > FS: 0000555556247300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > CR2: 00007ffe3d8e5ff8 CR3: 00000000215d4000 CR4: 00000000003506f0 > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > Call Trace: > > <TASK> > > vhost_worker_create drivers/vhost/vhost.c:580 [inline] > > The return value from vhost_task_create is incorrect if the kzalloc fails. > > Christian, here is a fix for what's in your tree. Do you want me to submit > a follow up patch like this or a replacement patch for: > > commit 77feab3c4156 ("vhost_task: Allow vhost layer to use copy_process") > > with the fix rolled into it? >> > >From 0677ad6d77722f301ca35e8e0f8fd0cbd5ed8484 Mon Sep 17 00:00:00 2001 > From: Mike Christie <michael.christie at oracle.com> > Date: Tue, 21 Mar 2023 12:39:39 -0500 > Subject: [PATCH] vhost_task: Fix vhost_task_create return value > > vhost_task_create is supposed to return the vhost_task or NULL on > failure. This fixes it to return the correct value when the allocation > of the struct fails. > --- > kernel/vhost_task.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/vhost_task.c b/kernel/vhost_task.c > index 4b8aff160640..b7cbd66f889e 100644 > --- a/kernel/vhost_task.c > +++ b/kernel/vhost_task.c > @@ -88,7 +88,7 @@ struct vhost_task *vhost_task_create(int (*fn)(void *), void *arg, > > vtsk = kzalloc(sizeof(*vtsk), GFP_KERNEL); > if (!vtsk) > - return ERR_PTR(-ENOMEM); > + return NULL; > init_completion(&vtsk->exited); > vtsk->data = arg; > vtsk->fn = fn; >