Hello DRM maintainers, This is a WARNING bug detected by syzkaller.
1. Description A kernel WARNING was triggered in drm_gem_object_handle_put_unlocked during the close() syscall on a DRM file descriptor. The issue appears to be related to GEM object handle management during the release process (drm_release). According to the log, the warning is located at drivers/gpu/drm/drm_gem.c:300. 2. Environment Kernel Branch: mainline Kernel Revision: v6.18 Kernel Config: https://gist.github.com/manual0/b8f4c12ea784620b3db92dbe56afedbb#file-gistfile1-txt Compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0 3. Syzkaller Report WARNING: CPU: 3 PID: 48617 at drivers/gpu/drm/drm_gem.c:300 drm_gem_object_handle_put_unlocked+0x30e/0x3e0 Modules linked in: CPU: 3 UID: 0 PID: 48617 Comm: syz.3.11626 Not tainted 6.18.0 #1 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 RIP: 0010:drm_gem_object_handle_put_unlocked+0x30e/0x3e0 Call Trace: <TASK> drm_gem_object_release_handle+0xc7/0x200 idr_for_each+0x119/0x230 lib/idr.c:208 drm_gem_release+0x29/0x40 drm_file_free.part.0+0x724/0xcf0 drm_close_helper.isra.0+0x183/0x1f0 drm_release+0x1ab/0x360 __fput+0x402/0xb50 fs/file_table.c:468 task_work_run+0x16b/0x260 kernel/task_work.c:227 exit_to_user_mode_loop+0xf9/0x130 do_syscall_64+0x424/0xfa0 arch/x86/entry/syscall_32.c:308 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Best regards, Zhi Wang
