On 10/16/15, Vasant Hegde <hegdevas...@linux.vnet.ibm.com> wrote: > On 10/16/2015 04:02 PM, Denis Kirjanov wrote: >> On 10/16/15, Vasant Hegde <hegdevas...@linux.vnet.ibm.com> wrote: >>> Currently we do not validate rtas entry before calling enter_rtas(). >>> This >>> is resulting in a kernel oops (see below) when user space calls rtas >>> system >>> call on PowerNV platform. We hit below oops when we ran trinity (system >>> call >>> fuzzer) on PowerNV. This patch adds code to validate rtas entry before >>> making >>> enter_rtas() call. >> >> Hi, >> have you figured out why we have null entry? > > Denis, > > Yes... On PowerNV platform we don't have RTAS.. Hence it's not initialized. But why do we have CONFIG_PPC_RTAS on OPAL machines then?
> > -Vasant > >> >> Thanks! >>> >>> dmesg: >>> ----- >>> [22061.541428] Oops: Exception in kernel mode, sig: 4 [#1] >>> [22061.541446] SMP NR_CPUS=1024 NUMA PowerNV >>> [22061.541453] Modules linked in: rfcomm bnep nfnetlink >>> scsi_transport_iscsi >>> hidp nfc af_802154 ieee802154 bluetooth rfkill pppoe pppox ppp_generic >>> slhc >>> irda crc_ccitt af_key sctp libcrc32c atm appletalk ipx p8023 psnap p8022 >>> ipt_MASQUERADE nf_nat_masquerade_ipv4 xt_CHECKSUM tun ip6t_rpfilter >>> ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_conntrack >>> ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables >>> ip6table_mangle ip6table_security ip6table_raw ip6table_filter >>> ip6_tables >>> iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat >>> nf_conntrack >>> iptable_mangle iptable_security iptable_raw windfarm_smu_sat ses >>> enclosure >>> windfarm_pid shpchp i2c_opal i2c_core kvm_hv kvm_pr dm_multipath kvm >>> lpfc >>> tg3 ptp pps_core scsi_transport_fc >>> [22061.541561] CPU: 40 PID: 57748 Comm: trinity-c11 Not tainted >>> 3.18.17-340.el7_1.pkvm3_1_0.2400.1.ppc64le #1 >>> [22061.541566] task: c000000004294b80 ti: c0000007e1a78000 task.ti: >>> c0000007e1a78000 >>> [22061.541570] NIP: 0000000000000000 LR: 0000000000009c14 CTR: >>> c000000000423140 >>> [22061.541573] REGS: c0000007e1a7b920 TRAP: 0e40 Not tainted >>> (3.18.17-340.el7_1.pkvm3_1_0.2400.1.ppc64le) >>> [22061.541577] MSR: 1000000000081000 <HV,ME> CR: 00000000 XER: >>> 00000000 >>> [22061.541585] CFAR: c000000000009c0c SOFTE: 0 >>> GPR00: 9000000000001031 c0000007e1a7bba0 c0000000012b1d00 >>> 0000000001338840 >>> GPR04: 0000000000000000 0000000000000000 1000000000001000 >>> 9000000000001033 >>> GPR08: 0000000040000000 8000000000002933 00003fff9e9d0068 >>> 0000000000000000 >>> GPR12: 00000000000000ff c000000007db7c00 0000000000000000 >>> 0000000000000000 >>> GPR16: 0000000000000000 0000000000000000 0000000000000000 >>> 0000000000000000 >>> GPR20: 0000000000000000 0000000000000000 0000000000000000 >>> 0000000000000000 >>> GPR24: 0000000000000000 000000000000dc58 0000000000000001 >>> c000001ee716e000 >>> GPR28: 0000000000000000 c000000001338840 00003fff9db30000 >>> 0000000000000000 >>> [22061.541629] NIP [0000000000000000] (null) >>> [22061.541637] LR [0000000000009c14] 0x9c14 >>> [22061.541640] Call Trace: >>> [22061.541649] [c0000007e1a7bba0] [c00000000041a7f4] >>> avc_has_perm_noaudit+0x54/0x110 (unreliable) >>> [22061.541657] [c0000007e1a7bd80] [c00000000002ddc0] >>> ppc_rtas+0x150/0x2d0 >>> [22061.541662] [c0000007e1a7be30] [c000000000009358] >>> syscall_exit+0x0/0x98 >>> [22061.541666] Instruction dump: >>> [22061.541669] XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX >>> XXXXXXXX XXXXXXXX >>> [22061.541675] XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX 60000000 60000000 >>> 60000000 60000000 >>> [22061.541688] ---[ end trace 6f9bf0b3d32096aa ]--- >>> >>> Reported-by: NAGESWARA R. SASTRY <nasas...@in.ibm.com> >>> Signed-off-by: Vasant Hegde <hegdevas...@linux.vnet.ibm.com> >>> --- >>> arch/powerpc/kernel/rtas.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c >>> index 84bf934..5a753fa 100644 >>> --- a/arch/powerpc/kernel/rtas.c >>> +++ b/arch/powerpc/kernel/rtas.c >>> @@ -1043,6 +1043,9 @@ asmlinkage int ppc_rtas(struct rtas_args __user >>> *uargs) >>> if (!capable(CAP_SYS_ADMIN)) >>> return -EPERM; >>> >>> + if (!rtas.entry) >>> + return -EINVAL; >>> + >>> if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0) >>> return -EFAULT; >>> >>> >>> _______________________________________________ >>> Linuxppc-dev mailing list >>> Linuxppc-dev@lists.ozlabs.org >>> https://lists.ozlabs.org/listinfo/linuxppc-dev >> > > _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
