bisecting fixing commit since c3d8f220d01220a5b253e422be407d068dc65511
building syzkaller on 1da71ab086c5d9e6a32beae37b109efaa856b257
testing commit c3d8f220d01220a5b253e422be407d068dc65511 with gcc (GCC) 8.1.0
kernel signature: 05c8d7830c28fca934ca90691a45490109eba3fdc7cbbaab6bbdc032ae63ada5
run #0: crashed: BUG: unable to handle kernel NULL pointer dereference in bpf_prog_ADDR
run #1: crashed: BUG: unable to handle kernel NULL pointer dereference in bpf_prog_ADDR
run #2: crashed: BUG: unable to handle kernel NULL pointer dereference in bpf_prog_ADDR
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
testing current HEAD 3d5e28bff7ad55aea081c1af516cc1c94a5eca7d
testing commit 3d5e28bff7ad55aea081c1af516cc1c94a5eca7d with gcc (GCC) 8.1.0
kernel signature: a896762c7ac6ba82114ba3397f096f6de9295771e5fcafb640db435cf64e3eea
all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in bpf_prog_ADDR
revisions tested: 2, total time: 26m34.281836147s (build: 9m54.650235845s, test: 16m2.786588266s)
the crash still happens on HEAD
commit msg: Merge branch 'stable/for-linus-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
crash: BUG: unable to handle kernel NULL pointer dereference in bpf_prog_ADDR
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 11e1dd067 P4D 11e1dd067 PUD 11e2fe067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP
CPU: 0 PID: 6594 Comm: syz-executor.3 Not tainted 5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bpf_prog_cd248b930ddf8412+0x11/0xae4
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 66 90 55 48 89 e5 31 c0 48 8b 47 28 <48> 8b 40 00 8b 80 00 01 00 00 c9 c3 cc cc cc cc cc cc cc cc cc cc
RSP: 0018:ffffc90000f67d10 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000018
RDX: ffffffffa009e51c RSI: ffffc90000ea1038 RDI: ffffc90000f67de0
RBP: ffffc90000f67d10 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000001 R11: ffff88811e11b100 R12: 0000000000029910
R13: 0000000000000001 R14: ffffc90000f67dd8 R15: 0000000000000001
FS:  00007fbb1da44700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000011e1b0000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 bpf_prog_run_xdp include/linux/filter.h:743 [inline]
 bpf_test_run+0x12c/0x4d0 net/bpf/test_run.c:48
 bpf_prog_test_run_xdp+0x126/0x1a0 net/bpf/test_run.c:648
 bpf_prog_test_run kernel/bpf/syscall.c:3125 [inline]
 __do_sys_bpf+0x443/0x1f50 kernel/bpf/syscall.c:4417
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d4d9
Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fbb1da43c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000001440 RCX: 000000000045d4d9
RDX: 0000000000000010 RSI: 0000000020001300 RDI: 000000000000000a
RBP: 000000000118d020 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cfec
R13: 00007ffcbf0953df R14: 00007fbb1da449c0 R15: 000000000118cfec
Modules linked in:
CR2: 0000000000000000
---[ end trace 144b2cce77df6e72 ]---
RIP: 0010:bpf_prog_cd248b930ddf8412+0x11/0xae4
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 66 90 55 48 89 e5 31 c0 48 8b 47 28 <48> 8b 40 00 8b 80 00 01 00 00 c9 c3 cc cc cc cc cc cc cc cc cc cc
RSP: 0018:ffffc90000f67d10 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000018
RDX: ffffffffa009e51c RSI: ffffc90000ea1038 RDI: ffffc90000f67de0
RBP: ffffc90000f67d10 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000001 R11: ffff88811e11b100 R12: 0000000000029910
R13: 0000000000000001 R14: ffffc90000f67dd8 R15: 0000000000000001
FS:  00007fbb1da44700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000011e1b0000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400