Hello, syzbot found the following issue on: HEAD commit: 3aaa8ce7a335 Merge tag 'mm-hotfixes-stable-2024-03-07-16-1.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=13e5861e180000 kernel config: https://syzkaller.appspot.com/x/.config?x=f8d2f8f66e9a667a dashboard link: https://syzkaller.appspot.com/bug?extid=6856926fbb5e9b794e5c compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10ed8171180000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13b728ae180000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/2a093f1b5a72/disk-3aaa8ce7.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/efa5cb929ca6/vmlinux-3aaa8ce7.xz kernel image: https://storage.googleapis.com/syzbot-assets/2b0c044e721b/bzImage-3aaa8ce7.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6856926fbb5e9b794e5c@xxxxxxxxxxxxxxxxxxxxxxxxx ===================================================== BUG: KMSAN: uninit-value in bpf_prog_test_run_xdp+0x1758/0x1a30 net/bpf/test_run.c:1277 bpf_prog_test_run_xdp+0x1758/0x1a30 net/bpf/test_run.c:1277 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:4107 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5475 __do_sys_bpf kernel/bpf/syscall.c:5561 [inline] __se_sys_bpf kernel/bpf/syscall.c:5559 [inline] __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5559 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was stored to memory at: bpf_test_run+0x515/0xaf0 bpf_prog_test_run_xdp+0xea5/0x1a30 net/bpf/test_run.c:1267 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:4107 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5475 __do_sys_bpf kernel/bpf/syscall.c:5561 [inline] __se_sys_bpf kernel/bpf/syscall.c:5559 [inline] __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5559 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was stored to memory at: ___bpf_prog_run+0x76dd/0xdb80 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2227 bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline] __bpf_prog_run include/linux/filter.h:651 [inline] bpf_prog_run_xdp include/net/xdp.h:514 [inline] bpf_test_run+0x42d/0xaf0 net/bpf/test_run.c:421 bpf_prog_test_run_xdp+0xea5/0x1a30 net/bpf/test_run.c:1267 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:4107 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5475 __do_sys_bpf kernel/bpf/syscall.c:5561 [inline] __se_sys_bpf kernel/bpf/syscall.c:5559 [inline] __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5559 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was stored to memory at: ___bpf_prog_run+0x8567/0xdb80 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2227 bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline] __bpf_prog_run include/linux/filter.h:651 [inline] bpf_prog_run_xdp include/net/xdp.h:514 [inline] bpf_test_run+0x42d/0xaf0 net/bpf/test_run.c:421 bpf_prog_test_run_xdp+0xea5/0x1a30 net/bpf/test_run.c:1267 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:4107 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5475 __do_sys_bpf kernel/bpf/syscall.c:5561 [inline] __se_sys_bpf kernel/bpf/syscall.c:5559 [inline] __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5559 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Local variable stack created at: __bpf_prog_run512+0x45/0xe0 kernel/bpf/core.c:2227 bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline] __bpf_prog_run include/linux/filter.h:651 [inline] bpf_prog_run_xdp include/net/xdp.h:514 [inline] bpf_test_run+0x42d/0xaf0 net/bpf/test_run.c:421 CPU: 0 PID: 5009 Comm: syz-executor369 Not tainted 6.8.0-rc7-syzkaller-00142-g3aaa8ce7a335 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 ===================================================== --- This report is generated by a bot. 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