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AHgh+RrP+V40iBNskOWWaP86VNAzH0zkMkHJSL1FIaIRWAzC5e1S9SP3VKmk946sWW3Zj8CpYAH3pP6S7IXX7aY=@vger.kernel.org X-Gm-Message-State: AFuF++mxZXJZlfIQBmwoQSKkm4pY0D8kP4DFiCtk39m0C/XMMD1uHfgo Eghq2Nwt8vfT1kobl4lhJ5HkgND6PZaOlQQHV8DG/3u987ECkEh0YGbkkgrT0y5DOzIUsGHJXWN 1BcRswwre5MsG5qrGGf8dwNiTeJIagmaDXr2Z6/eGiugDk/bVolM2/lDKk4U= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:4704:b0:4ab:224d:6dd6 with SMTP id 5614622812f47-4b2cddd4647mr25073978b6e.15.1787511220196; Sun, 23 Aug 2026 11:53:40 -0700 (PDT) Date: Sun, 23 Aug 2026 11:53:40 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a8b41b4.dbb3a75c.13dd47.0052.GAE@google.com> Subject: [syzbot] [net?] [usb?] UBSAN: shift-out-of-bounds in vcc_connect From: syzbot To: 3chas3@gmail.com, davem@davemloft.net, edumazet@google.com, horms@kernel.org, kuba@kernel.org, linux-atm-general@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: bd5f485f3f02 Merge tag 'soc-arm-7.3' of git://git.kernel.o.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=16736e79580000 kernel config: https://syzkaller.appspot.com/x/.config?x=6d6c2a05eaadaf10 dashboard link: https://syzkaller.appspot.com/bug?extid=6665d3db5fef15914802 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=133f2549580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/2da33ef8d789/disk-bd5f485f.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/7e8921e0c1e1/vmlinux-bd5f485f.xz kernel image: https://storage.googleapis.com/syzbot-assets/c7e5335b79c8/bzImage-bd5f485f.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6665d3db5fef15914802@syzkaller.appspotmail.com ------------[ cut here ]------------ UBSAN: shift-out-of-bounds in net/atm/common.c:381:10 shift exponent -1 is negative CPU: 0 UID: 0 PID: 6073 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 ubsan_epilogue+0xa/0x30 lib/ubsan.c:233 __ubsan_handle_shift_out_of_bounds+0x279/0x2a0 lib/ubsan.c:494 __vcc_connect net/atm/common.c:381 [inline] vcc_connect.cold+0xe0/0x123 net/atm/common.c:498 pvc_bind+0x33f/0x460 net/atm/pvc.c:52 __sys_bind_socket net/socket.c:1945 [inline] __sys_bind_socket net/socket.c:1937 [inline] __sys_bind+0x1a9/0x260 net/socket.c:1976 __do_sys_bind net/socket.c:1981 [inline] __se_sys_bind net/socket.c:1979 [inline] __x64_sys_bind+0x72/0xb0 net/socket.c:1979 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6a3099e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff44bcea08 EFLAGS: 00000246 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 00007f6a30c25fa0 RCX: 00007f6a3099e0d9 RDX: 000000000000000c RSI: 0000200000000100 RDI: 0000000000000004 RBP: 00007f6a30a35024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6a30c25fac R14: 00007f6a30c25fa0 R15: 00007f6a30c25fa0 ---[ end trace ]--- --- This report is generated by a bot. 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