[syzbot] [dri?] WARNING in drm_prime_fd_to_handle_ioctl

Sun Oct 15 03:37:47 UTC 2023

Hello,

syzbot found the following issue on:

HEAD commit:    1c8b86a3799f Merge tag 'xsa441-6.6-tag' of git://git.kerne..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=13005e31680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=32d0b9b42ceb8b10
dashboard link: https://syzkaller.appspot.com/bug?extid=0da81ccba2345eeb7f48
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=13c48345680000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=101b3679680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/45e9377886e9/disk-1c8b86a3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9511a41a6d1e/vmlinux-1c8b86a3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fac07e1c3c1a/bzImage-1c8b86a3.xz

The issue was bisected to:

commit 85e26dd5100a182bf8448050427539c0a66ab793
Author: Christian König <christian.koenig at amd.com>
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=14cf17f1680000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=16cf17f1680000
console output: https://syzkaller.appspot.com/x/log.txt?x=12cf17f1680000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0da81ccba2345eeb7f48 at syzkaller.appspotmail.com
Fixes: 85e26dd5100a ("drm/client: fix circular reference counting issue")

------------[ cut here ]------------
WARNING: CPU: 0 PID: 5040 at drivers/gpu/drm/drm_prime.c:326 drm_gem_prime_fd_to_handle drivers/gpu/drm/drm_prime.c:326 [inline]
WARNING: CPU: 0 PID: 5040 at drivers/gpu/drm/drm_prime.c:326 drm_prime_fd_to_handle_ioctl+0x555/0x600 drivers/gpu/drm/drm_prime.c:374
Modules linked in:
CPU: 0 PID: 5040 Comm: syz-executor405 Not tainted 6.6.0-rc5-syzkaller-00055-g1c8b86a3799f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:drm_gem_prime_fd_to_handle drivers/gpu/drm/drm_prime.c:326 [inline]
RIP: 0010:drm_prime_fd_to_handle_ioctl+0x555/0x600 drivers/gpu/drm/drm_prime.c:374
Code: 89 df e8 0e 9b 26 fd f0 48 ff 03 e9 7e fd ff ff e8 b0 dc d0 fc 4c 89 f7 44 89 eb e8 75 73 8b 05 e9 da fe ff ff e8 9b dc d0 fc <0f> 0b e9 5d fd ff ff e8 3f 94 26 fd e9 3a fc ff ff 48 8b 7c 24 08
RSP: 0018:ffffc90003a5fc70 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888018f14c00 RCX: 0000000000000000
RDX: ffff88801d691dc0 RSI: ffffffff84b6ea15 RDI: ffff8881476f3928
RBP: ffff88801fac5400 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff8881476f3800 R11: 0000000000000000 R12: ffffc90003a5fe10
R13: ffff8881476f3800 R14: ffff88801c590c10 R15: 0000000000000000
FS:  00005555555d6380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555db75f4058 CR3: 0000000072209000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 drm_ioctl_kernel+0x280/0x4c0 drivers/gpu/drm/drm_ioctl.c:789
 drm_ioctl+0x5cb/0xbf0 drivers/gpu/drm/drm_ioctl.c:892
 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:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f0c8214be69
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff6f4156f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0c8214be69
RDX: 0000000020000000 RSI: 00000000c00c642e RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000000000a0 R09: 00000000000000a0
R10: 00000000000000a0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0c821c3820 R14: 00007fff6f415720 R15: 00007fff6f415710
 </TASK>

---
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