Hello,
syzbot found the following issue on:
HEAD commit: f99c5f563c17 Merge tag 'nf-24-03-21' of git://git.kernel.o..
git tree: net
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1502f36d180000
kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440
dashboard link: https://syzkaller.appspot.com/bug?extid=f534bd500d914e34b59e
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=17ac600b180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1144b797180000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/65d3f3eb786e/disk-f99c5f56.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/799cf7f28ff8/vmlinux-f99c5f56.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ab26c60c3845/bzImage-f99c5f56.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]
RDX: 0000000000000050 RSI: 0000000020000000 RDI: 000000000000000a
RBP: 00007ffebb32f750 R08: 00007ffebb32f4e7 R09: 00007f2c42da0038
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffebb32f9b8 R14: 0000000000000001 R15: 0000000000000001
</TASK>
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5065 at net/core/xdp.c:299 __xdp_reg_mem_model+0x2d9/0x650 net/core/xdp.c:299
Modules linked in:
CPU: 0 PID: 5065 Comm: syz-executor883 Not tainted 6.8.0-syzkaller-05271-gf99c5f563c17 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:__xdp_reg_mem_model+0x2d9/0x650 net/core/xdp.c:299
Code: 89 c5 85 c0 79 62 e8 c6 b4 3e f8 eb a5 e8 bf b4 3e f8 4c 89 ff e8 97 a9 96 f8 4d 63 fd 48 c7 c7 80 27 39 8f e8 a8 36 23 02 90 <0f> 0b 90 e9 f8 01 00 00 e8 9a b4 3e f8 48 8d 7c 24 60 48 89 f8 48
RSP: 0018:ffffc90003d0f640 EFLAGS: 00010246
RAX: 1158ab1705932a00 RBX: dffffc0000000000 RCX: ffffffff8b7974ad
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc90003d0f5c0
RBP: ffffc90003d0f710 R08: ffffc90003d0f5c7 R09: 1ffff920007a1eb8
R10: dffffc0000000000 R11: fffff520007a1eb9 R12: 0000000000000002
R13: ffff88802ead6000 R14: 1ffff920007a1ed0 R15: fffffffffffffff4
FS: 0000555581756480(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000066c7e0 CR3: 0000000020174000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
xdp_reg_mem_model+0x22/0x40 net/core/xdp.c:344
xdp_test_run_setup net/bpf/test_run.c:188 [inline]
bpf_test_run_xdp_live+0x365/0x1e90 net/bpf/test_run.c:377
bpf_prog_test_run_xdp+0x813/0x11b0 net/bpf/test_run.c:1267
bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4240
__sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5649
__do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f2c42ddb279
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffebb32f748 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f2c42ddb279
RDX: 0000000000000050 RSI: 0000000020000000 RDI: 000000000000000a
RBP: 00007ffebb32f750 R08: 00007ffebb32f4e7 R09: 00007f2c42da0038
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffebb32f9b8 R14: 0000000000000001 R15: 0000000000000001
</TASK>
---
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syzbot has bisected this issue to:
commit 2b0cfa6e49566c8fa6759734cf821aa6e8271a9e
Author: Lorenzo Bianconi <[email protected]>
Date: Mon Feb 12 09:50:54 2024 +0000
net: add generic percpu page_pool allocator
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=151860d4980000
start commit: f99c5f563c17 Merge tag 'nf-24-03-21' of git://git.kernel.o..
git tree: net
final oops: https://syzkaller.appspot.com/x/report.txt?x=171860d4980000
console output: https://syzkaller.appspot.com/x/log.txt?x=131860d4980000
kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440
dashboard link: https://syzkaller.appspot.com/bug?extid=f534bd500d914e34b59e
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17ac600b180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1144b797180000
Reported-by: [email protected]
Fixes: 2b0cfa6e4956 ("net: add generic percpu page_pool allocator")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
> syzbot has bisected this issue to:
>
> commit 2b0cfa6e49566c8fa6759734cf821aa6e8271a9e
> Author: Lorenzo Bianconi <[email protected]>
> Date: Mon Feb 12 09:50:54 2024 +0000
>
> net: add generic percpu page_pool allocator
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=151860d4980000
> start commit: f99c5f563c17 Merge tag 'nf-24-03-21' of git://git.kernel.o..
> git tree: net
> final oops: https://syzkaller.appspot.com/x/report.txt?x=171860d4980000
> console output: https://syzkaller.appspot.com/x/log.txt?x=131860d4980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440
> dashboard link: https://syzkaller.appspot.com/bug?extid=f534bd500d914e34b59e
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17ac600b180000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1144b797180000
>
> Reported-by: [email protected]
> Fixes: 2b0cfa6e4956 ("net: add generic percpu page_pool allocator")
>
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
>
Looking at the code, the root cause of the issue is the WARN(1) in
__xdp_reg_mem_model routine. __mem_id_init_hash_table() can fail just if rht
allocation fails. Do we really need this WARN(1)? It has been introduced in the
commit below:
commit 8d5d88527587516bd58ff0f3810f07c38e65e2be
Author: Jesper Dangaard Brouer <[email protected]>
Date: Tue Apr 17 16:46:12 2018 +0200
xdp: rhashtable with allocator ID to pointer mapping
Regards,
Lorenzo