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Date:   Fri, 24 Jun 2022 06:10:22 -0700
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Subject: [syzbot] KASAN: null-ptr-deref Read in ida_free (2)
From:   syzbot <syzbot+aa620fb1ece874a3f34c@syzkaller.appspotmail.com>
To:     Julia.Lawall@inria.fr, andreyknvl@gmail.com, balbi@kernel.org,
        gregkh@linuxfoundation.org, hdanton@sina.com, jannh@google.com,
        jj251510319013@gmail.com, linux-kernel@vger.kernel.org,
        linux-usb@vger.kernel.org, schspa@gmail.com,
        stern@rowland.harvard.edu, syzkaller-bugs@googlegroups.com
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Hello,

syzbot found the following issue on:

HEAD commit:    08897940f458 Add linux-next specific files for 20220623
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=14fc8c60080000
kernel config:  https://syzkaller.appspot.com/x/.config?x=fb185a52c6ad0a8e
dashboard link: https://syzkaller.appspot.com/bug?extid=aa620fb1ece874a3f34c
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=116b4140080000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17ab12e4080000

The issue was bisected to:

commit f2d8c2606825317b77db1f9ba0fc26ef26160b30
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Mon Jun 13 14:17:03 2022 +0000

    usb: gadget: Fix non-unique driver names in raw-gadget driver

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=15b40318080000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=17b40318080000
console output: https://syzkaller.appspot.com/x/log.txt?x=13b40318080000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+aa620fb1ece874a3f34c@syzkaller.appspotmail.com
Fixes: f2d8c2606825 ("usb: gadget: Fix non-unique driver names in raw-gadget driver")

==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: null-ptr-deref in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
BUG: KASAN: null-ptr-deref in ida_free+0x1b6/0x2e0 lib/idr.c:510
Read of size 8 at addr 0000000000000000 by task syz-executor185/3627

CPU: 1 PID: 3627 Comm: syz-executor185 Not tainted 5.19.0-rc3-next-20220623-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 kasan_report+0xbe/0x1f0 mm/kasan/report.c:495
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 ida_free+0x1b6/0x2e0 lib/idr.c:510
 dev_free+0xec/0x700 drivers/usb/gadget/legacy/raw_gadget.c:212
 kref_put include/linux/kref.h:65 [inline]
 raw_release+0x219/0x290 drivers/usb/gadget/legacy/raw_gadget.c:424
 __fput+0x277/0x9d0 fs/file_table.c:317
 task_work_run+0xdd/0x1a0 kernel/task_work.c:177
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xb05/0x2a00 kernel/exit.c:795
 do_group_exit+0xd2/0x2f0 kernel/exit.c:925
 __do_sys_exit_group kernel/exit.c:936 [inline]
 __se_sys_exit_group kernel/exit.c:934 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:934
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f12d28b6bd9
Code: Unable to access opcode bytes at RIP 0x7f12d28b6baf.
RSP: 002b:00007ffea2859da8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f12d292b3f0 RCX: 00007f12d28b6bd9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 000000000000000b
R10: 00007ffea2857e00 R11: 0000000000000246 R12: 00007f12d292b3f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
 </TASK>
==================================================================


---
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection
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