bisecting fixing commit since 69b94dd6dcd14d9bfcba35a492f5e27c15cf4d0a
building syzkaller on 512651955aad51ef5f916aa2d84732e84d1c5e48
testing commit 69b94dd6dcd14d9bfcba35a492f5e27c15cf4d0a with gcc (GCC) 8.4.1 20210217
kernel signature: c1dd612cc27c5e625c196601d799e735e972210bc50ae0661c0cd68b870837c9
all runs: crashed: general protection fault in tcp_splice_read
testing current HEAD 7d7d1c0ab3eb7c8d8f63a126535018007823b207
testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 with gcc (GCC) 8.4.1 20210217
kernel signature: dd8b8ef1a0e6ee2faae1a7f225791e18f4138a1c36c265e07c0c8a7e94ddc867
all runs: crashed: general protection fault in tcp_splice_read
revisions tested: 2, total time: 22m52.673915479s (build: 16m0.070727244s, test: 6m22.306888247s)
the crash still happens on HEAD
commit msg: Linux 4.14.232
crash: general protection fault in tcp_splice_read
IPv6: ADDRCONF(NETDEV_CHANGE): vlan1: link becomes ready
device veth0_vlan entered promiscuous mode
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
IPv6: ADDRCONF(NETDEV_UP): veth1_to_batadv: link is not ready
general protection fault: 0000 [#1] PREEMPT SMP KASAN
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0
Modules linked in:
CPU: 1 PID: 7049 Comm: syz-executor.0 Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8881da02c4c0 task.stack: ffff8881dacc8000
RIP: 0010:tcp_splice_read+0x120/0x900 net/ipv4/tcp.c:779
RSP: 0018:ffff8881daccfbc8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 1ffff1103b599f7d RCX: 1ffff1103b4059b7
RDX: 000000000000000f RSI: ffff8881da02cd98 RDI: 0000000000000078
RBP: ffff8881daccfcf0 R08: ffff8881da02cdb8 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff8881daccfcc8 R15: ffff8881ec826000
FS:  00007f027aa44700(0000) GS:ffff8881f6700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005610ce48c140 CR3: 00000001da137005 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 smc_splice_read+0x189/0x220 net/smc/af_smc.c:1304
 sock_splice_read+0x92/0x120 net/socket.c:883
 do_splice_to+0xe3/0x120 fs/splice.c:880
 do_splice fs/splice.c:1173 [inline]
 SYSC_splice fs/splice.c:1402 [inline]
 SyS_splice+0xfcb/0x1590 fs/splice.c:1382
 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x463ca9
RSP: 002b:00007f027aa44188 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 000000000055bf00 RCX: 0000000000463ca9
RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00000000004ae538 R08: 0000000000000006 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055bf00
R13: 00007ffe961ffd1f R14: 00007f027aa44300 R15: 0000000000022000
Code: 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 be 07 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 64 24 18 49 8d 
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
7c 24 78 48 89 fa 48 c1 ea 03 <0f> 
IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready
b6 
batman_adv: batadv0: Interface activated: batadv_slave_0
04 02 84 c0 74 08 3c 03 0f 8e 06 06 00 00 31 c0 41 f6 44 
RIP: tcp_splice_read+0x120/0x900 net/ipv4/tcp.c:779 RSP: ffff8881daccfbc8
---[ end trace 42859183045292da ]---
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0