On Thu, Jun 6, 2019 at 2:19 AM Sasha Levin <sashal@xxxxxxxxxx> wrote: > > On Wed, Jun 05, 2019 at 03:04:26PM +0100, Daniel Dao wrote: > >Hi there, > > > >We are testing kernel 4.19.47 with some tools utilizing kprobe, > >resulting in panics that look like: > > > >[ 1085.318031] kernel tried to execute NX-protected page - exploit > >attempt? (uid: 65534) > >[ 1085.334028] BUG: unable to handle kernel paging request at ffffffffc0428000 > >[ 1085.349128] PGD 13a3e10067 P4D 13a3e10067 PUD 13a3e12067 PMD > >c1e860067 PTE 8000000bbd075061 > >[ 1085.365779] Oops: 0011 [#1] SMP KASAN PTI > >[ 1085.377879] CPU: 30 PID: 29734 Comm: nginx-fl Tainted: G B > >O 4.19.47-cloudflare-kasan-2019.6.0 #2019.6.0 > >[ 1085.396652] Hardware name: Quanta Computer Inc QuantaPlex > >T41S-2U/S2S-MB, BIOS S2S_3B10.03 06/21/2018 > >[ 1085.414041] RIP: 0010:0xffffffffc0428000 > >[ 1085.425965] Code: Bad RIP value. > >[ 1085.436832] RSP: 0018:ffff88a015e2fb18 EFLAGS: 00010246 > >[ 1085.449853] RAX: 0000000000000003 RBX: ffff889f73448900 RCX: 0000000000000218 > >[ 1085.464719] RDX: ffff889fe4893c00 RSI: 0000000000000002 RDI: ffff889f73448900 > >[ 1085.479626] RBP: ffff88a015e2fe18 R08: 0000000000000006 R09: 0000000000000000 > >[ 1085.494677] R10: 000000008a08850a R11: 0000000000000000 R12: ffff889f7344890c > >[ 1085.509890] R13: ffff889f73448c54 R14: ffff889f73448c7a R15: 0000000000002c19 > >[ 1085.525252] FS: 00007f51582f5680(0000) GS:ffff88a03fb80000(0000) > >knlGS:0000000000000000 > >[ 1085.541810] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > >[ 1085.555812] CR2: ffffffffc0427fd6 CR3: 0000002039fee004 CR4: 00000000001606e0 > >[ 1085.571154] Call Trace: > >[ 1085.581676] ? tcp_set_state+0x5/0x5b0 > >[ 1085.593532] ? tcp_v4_connect+0xbd7/0x2000 > >[ 1085.605809] ? tcp_sk_init+0x1220/0x1220 > >[ 1085.617810] ? selinux_socket_connect_helper.isra.55+0x277/0x400 > >[ 1085.631808] ? sock_poll+0x218/0x300 > >[ 1085.643407] ? selinux_netcache_avc_callback+0x30/0x30 > >[ 1085.656701] ? __inet_stream_connect+0x630/0xbd0 > >[ 1085.669508] ? expand_files.part.9+0x640/0x640 > >[ 1085.682145] ? ipip_gro_complete+0x110/0x110 > >[ 1085.694627] ? __inet_stream_connect+0xbd0/0xbd0 > >[ 1085.707397] ? inet_stream_connect+0x53/0xa0 > >[ 1085.719830] ? __sys_connect+0x1f6/0x270 > >[ 1085.731964] ? __ia32_sys_accept+0xb0/0xb0 > >[ 1085.744201] ? mutex_lock+0x85/0xe0 > >[ 1085.755815] ? ep_show_fdinfo+0x3c0/0x3c0 > >[ 1085.767916] ? syscall_trace_enter+0x566/0xc30 > >[ 1085.780429] ? __x64_sys_epoll_ctl+0x237/0x1080 > >[ 1085.792883] ? exit_to_usermode_loop+0x140/0x140 > >[ 1085.805425] ? __audit_syscall_exit+0x73e/0xa30 > >[ 1085.817925] ? __x64_sys_connect+0x6f/0xb0 > >[ 1085.829915] ? do_syscall_64+0x8e/0x280 > >[ 1085.841539] ? prepare_exit_to_usermode+0xe1/0x140 > >[ 1085.854067] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 > >[ 1085.867000] Modules linked in: xt_length xt_connlimit nf_conncount > >xt_hashlimit iptable_security sch_fq md_mod dm_crypt algif_skcipher > >af_alg dm_mod dax ip6table_nat nf_nat_ipv6 ip6table_mangle > >ip6table_security ip6table_raw xt_nat iptable_nat nf_nat_ipv4 nf_nat > >xt_TPROXY nf_tproxy_ipv6 nf_tproxy_ipv4 xt_connmark iptable_mangle > >xt_owner ip6table_filter ip6_tables xt_CT xt_socket nf_socket_ipv4 > >nf_socket_ipv6 iptable_raw nfnetlink_log xt_NFLOG xt_bpf xt_comment > >xt_conntrack xt_mark xt_multiport xt_set xt_tcpudp ipt_GLBREDIRECT(O) > >nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 fou ip6_udp_tunnel > >udp_tunnel iptable_filter bpfilter ip_set_hash_netport ip_set_hash_net > >ip_set_hash_ip ip_set nfnetlink sit ipip tunnel4 ip_tunnel tun 8021q > >garp stp mrp llc sb_edac x86_pkg_temp_thermal kvm_intel kvm irqbypass > >[ 1085.996378] crc32_pclmul crc32c_intel pcbc aesni_intel aes_x86_64 > >ipmi_ssif crypto_simd cryptd glue_helper intel_cstate intel_uncore > >sfc(O) intel_rapl_perf tpm_tis tpm_tis_core mdio tpm ipmi_si > >ipmi_devintf ipmi_msghandler efivarfs ip_tables x_tables > > > >Reproducible steps on my local machine are as follow: > >1. Run kernel 4.19.47 > >2. We are going to test kprobe on tcp_set_state using > >https://github.com/iovisor/bcc/blob/master/tools/tcplife.py. But > >probably any workload utilizing kprobe would work > > - Run some workload that creating tcp connections. I'm runing > >`python -m SimpleHTTPServer` and `wrk -d60s -c10 > >http://localhost:8000` > > - Run the script > >https://github.com/iovisor/bcc/blob/master/tools/tcplife.py. Expect it > >to not crash the kernel and producing some output > > > >Reverting commit 8715ce033eb37f539e73b1570bf56404b21d46cd makes it > >work for me locally. I also tested kernel > >5.2.0-rc3-00024-g788a024921c4 locally (latest Linus tree) and not > >seeing the issue, so maybe somewhere along the backporting process, we > >failed to backport all the required patches ? > > Uh, that might indeed be the case. Could you try cherry picking the > following 3 patches on top of your 4.19 tree and trying again? > > git cherry-pick d2a68c4effd821f0871d20368f76b609349c8a3b 3c0dab44e22782359a0a706cbce72de99a22aa75 7298e24f904224fa79eb8fd7e0fbd78950ccf2db I cant reproduce after cherry picking the 3 patches on top of 4.19.47. Thanks, Daniel.
