bisecting fixing commit since b98aebd298246df37b472c52a2ee1023256d02e3 building syzkaller on b602d64b5991c147af88f1e0f8d961c8b4b4a748 testing commit b98aebd298246df37b472c52a2ee1023256d02e3 with gcc (GCC) 8.1.0 kernel signature: d8e89e39511324a7e217e669a7a2057e5beaed7f8459ce32515cfa20c256fecb all runs: crashed: general protection fault in rdma_resolve_route testing current HEAD bae31eef2a167ef160ab2703b6a2f5bbecd98d92 testing commit bae31eef2a167ef160ab2703b6a2f5bbecd98d92 with gcc (GCC) 8.1.0 kernel signature: c060dd876ef1b6bc8fc40c476e774001f57facfa48ce4a8018f0b6445c9b149c all runs: crashed: general protection fault in rdma_resolve_route revisions tested: 2, total time: 24m52.372734441s (build: 16m48.687672267s, test: 6m55.625207251s) the crash still happens on HEAD commit msg: Linux 4.14.200 crash: general protection fault in rdma_resolve_route kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 1 PID: 21336 Comm: syz-executor.1 Not tainted 4.14.200-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88808d0b4340 task.stack: ffff888092a00000 RIP: 0010:rdma_cap_ib_sa include/rdma/ib_verbs.h:2682 [inline] RIP: 0010:rdma_resolve_route+0x10b/0x3040 drivers/infiniband/core/cma.c:2686 RSP: 0018:ffff888092a07960 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff8880a12bfb40 RCX: 0000000000000029 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000148 RBP: ffff888092a07b20 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a12bfcf8 R13: 0000000000000004 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007fc7ad77c700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9310618008 CR3: 0000000093b2c000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ucma_resolve_route+0xc0/0xf0 drivers/infiniband/core/ucma.c:740 ucma_write+0x1f1/0x2c0 drivers/infiniband/core/ucma.c:1672 __vfs_write+0xdb/0x840 fs/read_write.c:480 vfs_write+0x150/0x4f0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0x100/0x250 fs/read_write.c:582 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x459f79 RSP: 002b:00007fc7ad77bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f79 RDX: 0000000000000010 RSI: 0000000020000200 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc7ad77c6d4 R13: 00000000004d1978 R14: 00000000004e21d0 R15: 00000000ffffffff Code: ff df 48 c1 ea 03 80 3c 02 00 0f 85 52 23 00 00 48 ba 00 00 00 00 00 fc ff df 48 8b 03 48 8d b8 48 01 00 00 48 89 f9 48 c1 e9 03 <80> 3c 11 00 0f 85 3a 23 00 00 45 0f b6 f7 49 c1 e6 04 4c 03 b0 RIP: rdma_cap_ib_sa include/rdma/ib_verbs.h:2682 [inline] RSP: ffff888092a07960 RIP: rdma_resolve_route+0x10b/0x3040 drivers/infiniband/core/cma.c:2686 RSP: ffff888092a07960 ---[ end trace 0f45716bf00cbb72 ]---