On Tue, Jun 25, 2024 at 10:25 AM Geliang Tang <geliang@xxxxxxxxxx> wrote:
>
> From: Geliang Tang <tanggeliang@xxxxxxxxxx>
>
> Run the following BPF selftests on Loongarch:
>
> ./test_progs -t sockmap_listen
>
> A Kernel panic occurs:
>
> '''
> Oops[#1]:
> CPU: 49 PID: 233429 Comm: new_name Tainted: G OE 6.10.0-rc2+ #20
> Hardware name: LOONGSON Dabieshan/Loongson-TC542F0, BIOS Loongson-UDK2018-V4.0.11
> pc 0000000000000000 ra 90000000051ea4a0 tp 900030008549c000 sp 900030008549fe00
> a0 9000300152524a00 a1 0000000000000000 a2 900030008549fe38 a3 900030008549fe30
> a4 900030008549fe30 a5 90003000c58c8d80 a6 0000000000000000 a7 0000000000000039
> t0 0000000000000000 t1 90003000c58c8d80 t2 0000000000000001 t3 0000000000000000
> t4 0000000000000001 t5 900000011a1bf580 t6 900000011a3aff60 t7 000000000000006b
> t8 00000fffffffffff u0 0000000000000000 s9 00007fffbbe9e930 s0 9000300152524a00
> s1 90003000c58c8d00 s2 9000000006c81568 s3 0000000000000000 s4 90003000c58c8d80
> s5 00007ffff236a000 s6 00007ffffbc292b0 s7 00007ffffbc29998 s8 00007fffbbe9f180
> ra: 90000000051ea4a0 inet_release+0x60/0xc0
> ERA: 0000000000000000 0x0
> CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
> PRMD: 0000000c (PPLV0 +PIE +PWE)
> EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
> ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7)
> ESTAT: 00030000 [PIF] (IS= ECode=3 EsubCode=0)
> BADV: 0000000000000000
> PRID: 0014c011 (Loongson-64bit, Loongson-3C5000)
> Modules linked in: xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_nat_tftp
> Process new_name (pid: 233429, threadinfo=00000000b9196405, task=00000000c01df45b)
> Stack : 0000000000000000 90003000c58c8e20 90003000c58c8d00 900000000505960c
> 0000000000000000 9000000101c6ad20 9000300086524540 00000000082e0003
> 900030008bf57400 90000000050596bc 900030008bf57400 900000000434acac
> 0000000000000016 00007ffff224e060 00007fffbbe9f180 900030008bf57400
> 0000000000000000 9000000004341ce0 00007fffbbe9f180 00007ffff2369000
> 900030008549fec0 90000000054476ec 000000000000006b 9000000003f71da4
> 000000000000003a 00007ffff22b8a44 00007fffbbe9f8e0 00007fffbbe9e680
> ffffffffffffffda 0000000000000000 0000000000000000 0000000000000000
> 00007fffbbe9f288 0000000000000000 0000000000000000 0000000000000039
> 84c2431493ceab6e 84c23ceb2827425e 0000000000000007 00007ffff2271600
> ...
> Call Trace:
> [<900000000505960c>] __sock_release+0x4c/0xe0
> [<90000000050596bc>] sock_close+0x1c/0x40
> [<900000000434acac>] __fput+0xec/0x2e0
> [<9000000004341ce0>] sys_close+0x40/0xa0
> [<90000000054476ec>] do_syscall+0x8c/0xc0
> [<9000000003f71da4>] handle_syscall+0xc4/0x160
>
> Code: (Bad address in era)
>
> ---[ end trace 0000000000000000 ]---
> Kernel panic - not syncing: Fatal exception
> Kernel relocated by 0x3d50000
> .text @ 0x9000000003f50000
> .data @ 0x90000000055b0000
> .bss @ 0x9000000006ca9400
> ---[ end Kernel panic - not syncing: Fatal exception ]---
> '''
>
> This is because "sk->sk_prot->close" pointer is NULL in that case. This
> patch adds null check for it in inet_release() to fix this error.
>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Signed-off-by: Geliang Tang <tanggeliang@xxxxxxxxxx>
> ---
> net/ipv4/af_inet.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
> index b24d74616637..34a719e98c69 100644
> --- a/net/ipv4/af_inet.c
> +++ b/net/ipv4/af_inet.c
> @@ -434,7 +434,8 @@ int inet_release(struct socket *sock)
> if (sock_flag(sk, SOCK_LINGER) &&
> !(current->flags & PF_EXITING))
> timeout = sk->sk_lingertime;
> - sk->sk_prot->close(sk, timeout);
> + if (sk->sk_prot->close)
> + sk->sk_prot->close(sk, timeout);
Can you tell us which inet protocol does not have a ->close pointer ?
I find it hard to believe a day-0 bug only hit Loongarch arch in 2024.
