[syzbot] [dri?] WARNING in drm_gem_prime_fd_to_handle

From: syzbot
Date: Fri Dec 08 2023 - 00:52:26 EST


Hello,

syzbot found the following issue on:

HEAD commit: 33cc938e65a9 Linux 6.7-rc4
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1348e51ce80000
kernel config: https://syzkaller.appspot.com/x/.config?x=b50bd31249191be8
dashboard link: https://syzkaller.appspot.com/bug?extid=268d319a7bfd92f4ae01
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1552cce4e80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1065c954e80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ecc4a2a6bd50/disk-33cc938e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1be71f7cd7b2/vmlinux-33cc938e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/54de78eb11a7/bzImage-33cc938e.xz

The issue was bisected to:

commit 85e26dd5100a182bf8448050427539c0a66ab793
Author: Christian König <christian.koenig@xxxxxxx>
Date: Thu Jan 26 09:24:26 2023 +0000

drm/client: fix circular reference counting issue

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12624b4ae80000
final oops: https://syzkaller.appspot.com/x/report.txt?x=11624b4ae80000
console output: https://syzkaller.appspot.com/x/log.txt?x=16624b4ae80000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+268d319a7bfd92f4ae01@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 85e26dd5100a ("drm/client: fix circular reference counting issue")

------------[ cut here ]------------
WARNING: CPU: 1 PID: 5069 at drivers/gpu/drm/drm_prime.c:326 drm_gem_prime_fd_to_handle+0x4be/0x550 drivers/gpu/drm/drm_prime.c:326
Modules linked in:
CPU: 1 PID: 5069 Comm: syz-executor183 Not tainted 6.7.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:drm_gem_prime_fd_to_handle+0x4be/0x550 drivers/gpu/drm/drm_prime.c:326
Code: 00 00 48 89 df e8 72 71 6e ff e9 e9 fd ff ff e8 38 01 94 fc 4c 89 ff 41 89 dc e8 5d cd 8e 05 e9 b8 fe ff ff e8 23 01 94 fc 90 <0f> 0b 90 e9 47 fd ff ff e8 85 a7 ea fc e9 16 fc ff ff e8 7b a7 ea
RSP: 0018:ffffc90003d07c48 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888146686800 RCX: ffffffff84f3861b
RDX: ffff88807a279dc0 RSI: ffffffff84f3891d RDI: ffff888146686928
RBP: ffff88801f379c00 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff888146686800 R11: 0000000000000001 R12: ffff88801f378800
R13: ffff888143b66000 R14: ffffc90003d07e10 R15: ffff88801cbd8c10
FS: 00007f772497c6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000005fdeb8 CR3: 000000007d240000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
drm_prime_fd_to_handle_ioctl+0xcf/0x100 drivers/gpu/drm/drm_prime.c:375
drm_ioctl_kernel+0x28c/0x4d0 drivers/gpu/drm/drm_ioctl.c:792
drm_ioctl+0x5cb/0xbf0 drivers/gpu/drm/drm_ioctl.c:895
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f77249bd1b9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f772497c218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7724a45408 RCX: 00007f77249bd1b9
RDX: 0000000020000180 RSI: 00000000c00c642e RDI: 0000000000000004
RBP: 00007f7724a45400 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7724a4540c
R13: 00007f7724a12018 R14: 0023647261632f69 R15: 6972642f7665642f
</TASK>


---
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