syzbot ci has tested the following series [v1] bpf, test_run: Fix user-memory-access vulnerability for LIVE_FRAMES https://lore.kernel.org/all/[email protected] * [PATCH bpf-next 1/2] bpf, test_run: Fix user-memory-access vulnerability for LIVE_FRAMES * [PATCH bpf-next 2/2] selftests/bpf: Add test for xdp_md context with LIVE_FRAMES in BPF_PROG_TEST_RUN
and found the following issue: BUG: missing reserved tailroom Full report is available here: https://ci.syzbot.org/series/688d9198-9fed-495e-9113-3d4187428ee3 *** BUG: missing reserved tailroom tree: bpf-next URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/bpf/bpf-next.git base: a069190b590e108223cd841a1c2d0bfb92230ecc arch: amd64 compiler: Debian clang version 21.1.8 (++20251202083448+f68f64eb8130-1~exp1~20251202083504.46), Debian LLD 21.1.8 config: https://ci.syzbot.org/builds/3375fbfc-d3f8-45a8-8db2-62ac76ebb7b4/config C repro: https://ci.syzbot.org/findings/37614d32-0f44-4a1c-9822-586c95cfeb11/c_repro syz repro: https://ci.syzbot.org/findings/37614d32-0f44-4a1c-9822-586c95cfeb11/syz_repro ------------[ cut here ]------------ XDP_WARN: xdp_update_frame_from_buff(line:414): Driver BUG: missing reserved tailroom WARNING: net/core/xdp.c:618 at xdp_warn+0x1d/0x40 net/core/xdp.c:618, CPU#1: syz.0.17/5990 Modules linked in: CPU: 1 UID: 0 PID: 5990 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:xdp_warn+0x25/0x40 net/core/xdp.c:618 Code: 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 89 d3 49 89 f6 49 89 ff e8 da 83 63 f8 48 8d 3d e3 de 70 06 4c 89 f6 89 da 4c 89 f9 <67> 48 0f b9 3a 5b 41 5e 41 5f c3 cc cc cc cc cc 66 66 2e 0f 1f 84 RSP: 0018:ffffc90004427580 EFLAGS: 00010293 RAX: ffffffff895fc996 RBX: 000000000000019e RCX: ffffffff8c94c7e0 RDX: 000000000000019e RSI: ffffffff8da38c06 RDI: ffffffff8fd0a880 RBP: 0000000000000f68 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881b4ae3ec0 R13: ffff8881b4ae3198 R14: ffffffff8da38c06 R15: ffffffff8c94c7e0 FS: 000055555699b500(0000) GS:ffff8882a9a1f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30463fff CR3: 0000000175022000 CR4: 00000000000006f0 Call Trace: <TASK> xdp_update_frame_from_buff include/net/xdp.h:414 [inline] xdp_test_run_init_page+0x482/0x590 net/bpf/test_run.c:143 page_pool_set_pp_info net/core/page_pool.c:716 [inline] __page_pool_alloc_netmems_slow+0x33c/0x710 net/core/page_pool.c:631 page_pool_alloc_netmems net/core/page_pool.c:667 [inline] page_pool_alloc_pages+0xe6/0x1f0 net/core/page_pool.c:675 page_pool_dev_alloc_pages include/net/page_pool/helpers.h:96 [inline] xdp_test_run_batch net/bpf/test_run.c:294 [inline] bpf_test_run_xdp_live+0x714/0x1cf0 net/bpf/test_run.c:378 bpf_prog_test_run_xdp+0x7d2/0x1120 net/bpf/test_run.c:1387 bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4698 __sys_bpf+0x643/0x950 kernel/bpf/syscall.c:6220 __do_sys_bpf kernel/bpf/syscall.c:6315 [inline] __se_sys_bpf kernel/bpf/syscall.c:6313 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6313 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf0/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f389319acb9 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:00007ffc43c08dd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f3893405fa0 RCX: 00007f389319acb9 RDX: 0000000000000048 RSI: 0000200000000600 RDI: 000000000000000a RBP: 00007f3893208bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3893405fac R14: 00007f3893405fa0 R15: 00007f3893405fa0 </TASK> ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: f3 0f 1e fa endbr64 9: 41 57 push %r15 b: 41 56 push %r14 d: 53 push %rbx e: 89 d3 mov %edx,%ebx 10: 49 89 f6 mov %rsi,%r14 13: 49 89 ff mov %rdi,%r15 16: e8 da 83 63 f8 call 0xf86383f5 1b: 48 8d 3d e3 de 70 06 lea 0x670dee3(%rip),%rdi # 0x670df05 22: 4c 89 f6 mov %r14,%rsi 25: 89 da mov %ebx,%edx 27: 4c 89 f9 mov %r15,%rcx * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 5b pop %rbx 30: 41 5e pop %r14 32: 41 5f pop %r15 34: c3 ret 35: cc int3 36: cc int3 37: cc int3 38: cc int3 39: cc int3 3a: 66 data16 3b: 66 data16 3c: 2e cs 3d: 0f .byte 0xf 3e: 1f (bad) 3f: 84 .byte 0x84 *** If these findings have caused you to resend the series or submit a separate fix, please add the following tag to your commit message: Tested-by: [email protected] --- This report is generated by a bot. It may contain errors. syzbot ci engineers can be reached at [email protected].
