Check the return value of enable_metric_set #14

matt-auld · 2016-02-15T11:47:25Z

Looking at the generated configuration code there is potential forenable_metric_set to fail for some code paths

The text was updated successfully, but these errors were encountered:

Fixes segmentation fault using, for instance: (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64 [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. 0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 (gdb) bt #0 0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 #1 0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:433 #2 0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:498 #3 0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:936 #4 0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391 #5 0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361 #6 0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401 #7 0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253 #8 0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364 #9 0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664 #10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539 #11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264 #12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390 #13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451 #14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495 #15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618 (gdb) Intel PT attempts to find the sched:sched_switch tracepoint but that seg faults if tracefs is not readable, because the error reporting structure is null, as errors are not reported when automatically adding tracepoints. Fix by checking before using. Committer note: This doesn't take place in a kernel that supports perf_event_attr.context_switch, that is the default way that will be used for tracking context switches, only in older kernels, like 4.2, in a machine with Intel PT (e.g. Broadwell) for non-priviledged users. Further info from a similar patch by Wang: The error is in tracepoint_error: it assumes the 'e' parameter is valid. However, there are many situation a parse_event() can be called without parse_events_error. See result of $ grep 'parse_events(.*NULL)' ./tools/perf/ -r' Signed-off-by: Adrian Hunter <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Tong Zhang <[email protected]> Cc: Wang Nan <[email protected]> Cc: [email protected] # v4.4+ Fixes: 1965817 ("perf tools: Enhance parsing events tracepoint error output") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

When opening a file, SMB2_open() attempts to parse the lease state from the SMB2 CREATE Response. However, the parsing code was not careful to ensure that the create contexts are not empty or invalid, which can lead to out- of-bounds memory access. This can be seen easily by trying to read a file from a OSX 10.11 SMB3 server. Here is sample crash output: BUG: unable to handle kernel paging request at ffff8800a1a77cc6 IP: [<ffffffff8828a734>] SMB2_open+0x804/0x960 PGD 8f77067 PUD 0 Oops: 0000 [rib#1] SMP Modules linked in: CPU: 3 PID: 2876 Comm: cp Not tainted 4.5.0-rc3.x86_64.1+ rib#14 Hardware name: NETGEAR ReadyNAS 314 /ReadyNAS 314 , BIOS 4.6.5 10/11/2012 task: ffff880073cdc080 ti: ffff88005b31c000 task.ti: ffff88005b31c000 RIP: 0010:[<ffffffff8828a734>] [<ffffffff8828a734>] SMB2_open+0x804/0x960 RSP: 0018:ffff88005b31fa08 EFLAGS: 00010282 RAX: 0000000000000015 RBX: 0000000000000000 RCX: 0000000000000006 RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff88007eb8c8b0 RBP: ffff88005b31fad8 R08: 666666203d206363 R09: 6131613030383866 R10: 3030383866666666 R11: 00000000000002b0 R12: ffff8800660fd800 R13: ffff8800a1a77cc2 R14: 00000000424d53fe R15: ffff88005f5a28c0 FS: 00007f7c8a2897c0(0000) GS:ffff88007eb80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffff8800a1a77cc6 CR3: 000000005b281000 CR4: 00000000000006e0 Stack: ffff88005b31fa70 ffffffff88278789 00000000000001d3 ffff88005f5a2a80 ffffffff00000003 ffff88005d029d00 ffff88006fde05a0 0000000000000000 ffff88005b31fc78 ffff88006fde0780 ffff88005b31fb2f 0000000100000fe0 Call Trace: [<ffffffff88278789>] ? cifsConvertToUTF16+0x159/0x2d0 [<ffffffff8828cf68>] smb2_open_file+0x98/0x210 [<ffffffff8811e80c>] ? __kmalloc+0x1c/0xe0 [<ffffffff882685f4>] cifs_open+0x2a4/0x720 [<ffffffff88122cef>] do_dentry_open+0x1ff/0x310 [<ffffffff88268350>] ? cifsFileInfo_get+0x30/0x30 [<ffffffff88123d92>] vfs_open+0x52/0x60 [<ffffffff88131dd0>] path_openat+0x170/0xf70 [<ffffffff88097d48>] ? remove_wait_queue+0x48/0x50 [<ffffffff88133a29>] do_filp_open+0x79/0xd0 [<ffffffff8813f2ca>] ? __alloc_fd+0x3a/0x170 [<ffffffff881240c4>] do_sys_open+0x114/0x1e0 [<ffffffff881241a9>] SyS_open+0x19/0x20 [<ffffffff8896e257>] entry_SYSCALL_64_fastpath+0x12/0x6a Code: 4d 8d 6c 07 04 31 c0 4c 89 ee e8 47 6f e5 ff 31 c9 41 89 ce 44 89 f1 48 c7 c7 28 b1 bd 88 31 c0 49 01 cd 4c 89 ee e8 2b 6f e5 ff <45> 0f b7 75 04 48 c7 c7 31 b1 bd 88 31 c0 4d 01 ee 4c 89 f6 e8 RIP [<ffffffff8828a734>] SMB2_open+0x804/0x960 RSP <ffff88005b31fa08> CR2: ffff8800a1a77cc6 ---[ end trace d9f69ba64feee469 ]--- Signed-off-by: Justin Maggard <[email protected]> Signed-off-by: Steve French <[email protected]> CC: Stable <[email protected]>

rib · 2016-03-24T21:16:08Z

Good catch, thanks. The latest i915 perf checks the return value of enable_metric_set.

As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 torvalds#26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <[email protected]> Cc: Hannes Sowa <[email protected]> Signed-off-by: Jon Maxwell <[email protected]> Signed-off-by: David S. Miller <[email protected]>

commit 4dfce57 upstream. There have been several reports over the years of NULL pointer dereferences in xfs_trans_log_inode during xfs_fsr processes, when the process is doing an fput and tearing down extents on the temporary inode, something like: BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 PID: 29439 TASK: ffff880550584fa0 CPU: 6 COMMAND: "xfs_fsr" [exception RIP: xfs_trans_log_inode+0x10] rib#9 [ffff8800a57bbbe0] xfs_bunmapi at ffffffffa037398e [xfs] rib#10 [ffff8800a57bbce8] xfs_itruncate_extents at ffffffffa0391b29 [xfs] rib#11 [ffff8800a57bbd88] xfs_inactive_truncate at ffffffffa0391d0c [xfs] rib#12 [ffff8800a57bbdb8] xfs_inactive at ffffffffa0392508 [xfs] rib#13 [ffff8800a57bbdd8] xfs_fs_evict_inode at ffffffffa035907e [xfs] rib#14 [ffff8800a57bbe00] evict at ffffffff811e1b67 rib#15 [ffff8800a57bbe28] iput at ffffffff811e23a5 rib#16 [ffff8800a57bbe58] dentry_kill at ffffffff811dcfc8 rib#17 [ffff8800a57bbe88] dput at ffffffff811dd06c rib#18 [ffff8800a57bbea8] __fput at ffffffff811c823b rib#19 [ffff8800a57bbef0] ____fput at ffffffff811c846e rib#20 [ffff8800a57bbf00] task_work_run at ffffffff81093b27 rib#21 [ffff8800a57bbf30] do_notify_resume at ffffffff81013b0c rib#22 [ffff8800a57bbf50] int_signal at ffffffff8161405d As it turns out, this is because the i_itemp pointer, along with the d_ops pointer, has been overwritten with zeros when we tear down the extents during truncate. When the in-core inode fork on the temporary inode used by xfs_fsr was originally set up during the extent swap, we mistakenly looked at di_nextents to determine whether all extents fit inline, but this misses extents generated by speculative preallocation; we should be using if_bytes instead. This mistake corrupts the in-memory inode, and code in xfs_iext_remove_inline eventually gets bad inputs, causing it to memmove and memset incorrect ranges; this became apparent because the two values in ifp->if_u2.if_inline_ext[1] contained what should have been in d_ops and i_itemp; they were memmoved due to incorrect array indexing and then the original locations were zeroed with memset, again due to an array overrun. Fix this by properly using i_df.if_bytes to determine the number of extents, not di_nextents. Thanks to dchinner for looking at this with me and spotting the root cause. Signed-off-by: Eric Sandeen <[email protected]> Reviewed-by: Brian Foster <[email protected]> Signed-off-by: Dave Chinner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 1c7de2b upstream. There is at least one Chelsio 10Gb card which uses VPD area to store some non-standard blocks (example below). However pci_vpd_size() returns the length of the first block only assuming that there can be only one VPD "End Tag". Since 4e1a635 ("vfio/pci: Use kernel VPD access functions"), VFIO blocks access beyond that offset, which prevents the guest "cxgb3" driver from probing the device. The host system does not have this problem as its driver accesses the config space directly without pci_read_vpd(). Add a quirk to override the VPD size to a bigger value. The maximum size is taken from EEPROMSIZE in drivers/net/ethernet/chelsio/cxgb3/common.h. We do not read the tag as the cxgb3 driver does as the driver supports writing to EEPROM/VPD and when it writes, it only checks for 8192 bytes boundary. The quirk is registered for all devices supported by the cxgb3 driver. This adds a quirk to the PCI layer (not to the cxgb3 driver) as the cxgb3 driver itself accesses VPD directly and the problem only exists with the vfio-pci driver (when cxgb3 is not running on the host and may not be even loaded) which blocks accesses beyond the first block of VPD data. However vfio-pci itself does not have quirks mechanism so we add it to PCI. This is the controller: Ethernet controller [0200]: Chelsio Communications Inc T310 10GbE Single Port Adapter [1425:0030] This is what I parsed from its VPD: === b'\x82*\x0010 Gigabit Ethernet-SR PCI Express Adapter\x90J\x00EC\x07D76809 FN\x0746K' 0000 Large item 42 bytes; name 0x2 Identifier String b'10 Gigabit Ethernet-SR PCI Express Adapter' 002d Large item 74 bytes; name 0x10 #00 [EC] len=7: b'D76809 ' #0a [FN] len=7: b'46K7897' rib#14 [PN] len=7: b'46K7897' #1e [MN] len=4: b'1037' rib#25 [FC] len=4: b'5769' #2c [SN] len=12: b'YL102035603V' #3b [NA] len=12: b'00145E992ED1' 007a Small item 1 bytes; name 0xf End Tag 0c00 Large item 16 bytes; name 0x2 Identifier String b'S310E-SR-X ' 0c13 Large item 234 bytes; name 0x10 #00 [PN] len=16: b'TBD ' rib#13 [EC] len=16: b'110107730D2 ' torvalds#26 [SN] len=16: b'97YL102035603V ' torvalds#39 [NA] len=12: b'00145E992ED1' torvalds#48 [V0] len=6: b'175000' torvalds#51 [V1] len=6: b'266666' #5a [V2] len=6: b'266666' torvalds#63 [V3] len=6: b'2000 ' #6c [V4] len=2: b'1 ' torvalds#71 [V5] len=6: b'c2 ' #7a [V6] len=6: b'0 ' torvalds#83 [V7] len=2: b'1 ' torvalds#88 [V8] len=2: b'0 ' #8d [V9] len=2: b'0 ' torvalds#92 [VA] len=2: b'0 ' torvalds#97 [RV] len=80: b's\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'... 0d00 Large item 252 bytes; name 0x11 #00 [VC] len=16: b'122310_1222 dp ' rib#13 [VD] len=16: b'610-0001-00 H1\x00\x00' torvalds#26 [VE] len=16: b'122310_1353 fp ' torvalds#39 [VF] len=16: b'610-0001-00 H1\x00\x00' #4c [RW] len=173: b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'... 0dff Small item 0 bytes; name 0xf End Tag 10f3 Large item 13315 bytes; name 0x62 !!! unknown item name 98: b'\xd0\x03\x00@`\x0c\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00' === Signed-off-by: Alexey Kardashevskiy <[email protected]> Signed-off-by: Bjorn Helgaas <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: rib#8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . rib#9 [] tcp_rcv_established at ffffffff81580b64 rib#10 [] tcp_v4_do_rcv at ffffffff8158b54a rib#11 [] tcp_v4_rcv at ffffffff8158cd02 rib#12 [] ip_local_deliver_finish at ffffffff815668f4 rib#13 [] ip_local_deliver at ffffffff81566bd9 rib#14 [] ip_rcv_finish at ffffffff8156656d rib#15 [] ip_rcv at ffffffff81566f06 rib#16 [] __netif_receive_skb_core at ffffffff8152b3a2 rib#17 [] __netif_receive_skb at ffffffff8152b608 rib#18 [] netif_receive_skb at ffffffff8152b690 rib#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] rib#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] rib#21 [] net_rx_action at ffffffff8152bac2 rib#22 [] __do_softirq at ffffffff81084b4f rib#23 [] call_softirq at ffffffff8164845c rib#24 [] do_softirq at ffffffff81016fc5 rib#25 [] irq_exit at ffffffff81084ee5 torvalds#26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <[email protected]> Cc: Hannes Sowa <[email protected]> Signed-off-by: Jon Maxwell <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

If we *know* that the engine is idle, i.e. we have not more contexts in flight, we can skip any spurious CSB idle interrupts. These spurious interrupts seem to arrive long after we assert that the engines are completely idle, triggering later assertions: [ 178.896646] intel_engine_is_idle(bcs): interrupt not handled, irq_posted=2 [ 178.896655] ------------[ cut here ]------------ [ 178.896658] kernel BUG at drivers/gpu/drm/i915/intel_engine_cs.c:226! [ 178.896661] invalid opcode: 0000 [rib#1] SMP [ 178.896663] Modules linked in: i915(E) x86_pkg_temp_thermal(E) crct10dif_pclmul(E) crc32_pclmul(E) crc32c_intel(E) ghash_clmulni_intel(E) nls_ascii(E) nls_cp437(E) vfat(E) fat(E) intel_gtt(E) i2c_algo_bit(E) drm_kms_helper(E) syscopyarea(E) sysfillrect(E) sysimgblt(E) fb_sys_fops(E) aesni_intel(E) prime_numbers(E) evdev(E) aes_x86_64(E) drm(E) crypto_simd(E) cryptd(E) glue_helper(E) mei_me(E) mei(E) lpc_ich(E) efivars(E) mfd_core(E) battery(E) video(E) acpi_pad(E) button(E) tpm_tis(E) tpm_tis_core(E) tpm(E) autofs4(E) i2c_i801(E) fan(E) thermal(E) i2c_designware_platform(E) i2c_designware_core(E) [ 178.896694] CPU: 1 PID: 522 Comm: gem_exec_whispe Tainted: G E 4.11.0-rc5+ rib#14 [ 178.896702] task: ffff88040aba8d40 task.stack: ffffc900003f0000 [ 178.896722] RIP: 0010:intel_engine_init_global_seqno+0x1db/0x1f0 [i915] [ 178.896725] RSP: 0018:ffffc900003f3ab0 EFLAGS: 00010246 [ 178.896728] RAX: 0000000000000000 RBX: ffff88040af54000 RCX: 0000000000000000 [ 178.896731] RDX: ffff88041ec933e0 RSI: ffff88041ec8cc48 RDI: ffff88041ec8cc48 [ 178.896734] RBP: ffffc900003f3ac8 R08: 0000000000000000 R09: 000000000000047d [ 178.896736] R10: 0000000000000040 R11: ffff88040b344f80 R12: 0000000000000000 [ 178.896739] R13: ffff88040bce0000 R14: ffff88040bce52d8 R15: ffff88040bce0000 [ 178.896742] FS: 00007f2cccc2d8c0(0000) GS:ffff88041ec80000(0000) knlGS:0000000000000000 [ 178.896746] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 178.896749] CR2: 00007f41ddd8f000 CR3: 000000040bb03000 CR4: 00000000001406e0 [ 178.896752] Call Trace: [ 178.896768] reset_all_global_seqno.part.33+0x4e/0xd0 [i915] [ 178.896782] i915_gem_request_alloc+0x304/0x330 [i915] [ 178.896795] i915_gem_do_execbuffer+0x8a1/0x17d0 [i915] [ 178.896799] ? remove_wait_queue+0x48/0x50 [ 178.896812] ? i915_wait_request+0x300/0x590 [i915] [ 178.896816] ? wake_up_q+0x70/0x70 [ 178.896819] ? refcount_dec_and_test+0x11/0x20 [ 178.896823] ? reservation_object_add_excl_fence+0xa5/0x100 [ 178.896835] i915_gem_execbuffer2+0xab/0x1f0 [i915] [ 178.896844] drm_ioctl+0x1e6/0x460 [drm] [ 178.896858] ? i915_gem_execbuffer+0x260/0x260 [i915] [ 178.896862] ? dput+0xcf/0x250 [ 178.896866] ? full_proxy_release+0x66/0x80 [ 178.896869] ? mntput+0x1f/0x30 [ 178.896872] do_vfs_ioctl+0x8f/0x5b0 [ 178.896875] ? ____fput+0x9/0x10 [ 178.896878] ? task_work_run+0x80/0xa0 [ 178.896881] SyS_ioctl+0x3c/0x70 [ 178.896885] entry_SYSCALL_64_fastpath+0x17/0x98 [ 178.896888] RIP: 0033:0x7f2ccb455ca7 [ 178.896890] RSP: 002b:00007ffcabec72d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 178.896894] RAX: ffffffffffffffda RBX: 000055f897a44b90 RCX: 00007f2ccb455ca7 [ 178.896897] RDX: 00007ffcabec74a0 RSI: 0000000040406469 RDI: 0000000000000003 [ 178.896900] RBP: 00007f2ccb70a440 R08: 00007f2ccb70d0a4 R09: 0000000000000000 [ 178.896903] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 178.896905] R13: 000055f89782d71a R14: 00007ffcabecf838 R15: 0000000000000003 [ 178.896908] Code: 00 31 d2 4c 89 ef 8d 70 48 41 ff 95 f8 06 00 00 e9 68 fe ff ff be 0f 00 00 00 48 c7 c7 48 dc 37 a0 e8 fa 33 d6 e0 e9 0b ff ff ff <0f> 0b 0f 0b 0f 0b 0f 0b 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 On the other hand, by ignoring the interrupt do we risk running out of space in CSB ring? Testing for a few hours suggests not, i.e. that we only seem to get the odd delayed CSB idle notification. Signed-off-by: Chris Wilson <[email protected]> Cc: Tvrtko Ursulin <[email protected]> Reviewed-by: Joonas Lahtinen <[email protected]> Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]

[ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: rib#8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . rib#9 [] tcp_rcv_established at ffffffff81580b64 rib#10 [] tcp_v4_do_rcv at ffffffff8158b54a rib#11 [] tcp_v4_rcv at ffffffff8158cd02 rib#12 [] ip_local_deliver_finish at ffffffff815668f4 rib#13 [] ip_local_deliver at ffffffff81566bd9 rib#14 [] ip_rcv_finish at ffffffff8156656d rib#15 [] ip_rcv at ffffffff81566f06 rib#16 [] __netif_receive_skb_core at ffffffff8152b3a2 rib#17 [] __netif_receive_skb at ffffffff8152b608 rib#18 [] netif_receive_skb at ffffffff8152b690 rib#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] rib#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] rib#21 [] net_rx_action at ffffffff8152bac2 rib#22 [] __do_softirq at ffffffff81084b4f rib#23 [] call_softirq at ffffffff8164845c rib#24 [] do_softirq at ffffffff81016fc5 rib#25 [] irq_exit at ffffffff81084ee5 torvalds#26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <[email protected]> Cc: Hannes Sowa <[email protected]> Signed-off-by: Jon Maxwell <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

for_each_set_bit() only accepts variable of type unsigned long, and we can not cast it from smaller types. [ 16.499365] ================================================================== [ 16.506655] BUG: KASAN: stack-out-of-bounds in find_first_bit+0x1d/0x70 [ 16.513313] Read of size 8 at addr ffff8803616cf510 by task systemd-udevd/180 [ 16.521998] CPU: 0 PID: 180 Comm: systemd-udevd Tainted: G U O 4.15.0-rc3+ rib#14 [ 16.530317] Hardware name: Dell Inc. OptiPlex 7040/0Y7WYT, BIOS 1.2.8 01/26/2016 [ 16.537760] Call Trace: [ 16.540230] dump_stack+0x7c/0xbb [ 16.543569] print_address_description+0x6b/0x290 [ 16.548306] kasan_report+0x28a/0x370 [ 16.551993] ? find_first_bit+0x1d/0x70 [ 16.555858] find_first_bit+0x1d/0x70 [ 16.559625] intel_gvt_init_cmd_parser+0x127/0x3c0 [i915] [ 16.565060] ? __lock_is_held+0x8f/0xf0 [ 16.568990] ? intel_gvt_clean_cmd_parser+0x10/0x10 [i915] [ 16.574514] ? __hrtimer_init+0x5d/0xb0 [ 16.578445] intel_gvt_init_device+0x2c3/0x690 [i915] [ 16.583537] ? unregister_module_notifier+0x20/0x20 [ 16.588515] intel_gvt_init+0x89/0x100 [i915] [ 16.592962] i915_driver_load+0x1992/0x1c70 [i915] [ 16.597846] ? __i915_printk+0x210/0x210 [i915] [ 16.602410] ? wait_for_completion+0x280/0x280 [ 16.606883] ? lock_downgrade+0x2c0/0x2c0 [ 16.610923] ? __pm_runtime_resume+0x46/0x90 [ 16.615238] ? acpi_dev_found+0x76/0x80 [ 16.619162] ? i915_pci_remove+0x30/0x30 [i915] [ 16.623733] local_pci_probe+0x74/0xe0 [ 16.627518] pci_device_probe+0x208/0x310 [ 16.631561] ? pci_device_remove+0x100/0x100 [ 16.635871] ? __list_add_valid+0x29/0xa0 [ 16.639919] driver_probe_device+0x40b/0x6b0 [ 16.644223] ? driver_probe_device+0x6b0/0x6b0 [ 16.648696] __driver_attach+0x11d/0x130 [ 16.652649] bus_for_each_dev+0xe7/0x160 [ 16.656600] ? subsys_dev_iter_exit+0x10/0x10 [ 16.660987] ? __list_add_valid+0x29/0xa0 [ 16.665028] bus_add_driver+0x31d/0x3a0 [ 16.668893] driver_register+0xc6/0x170 [ 16.672758] ? 0xffffffffc0ad8000 [ 16.676108] do_one_initcall+0x9c/0x206 [ 16.679984] ? initcall_blacklisted+0x150/0x150 [ 16.684545] ? do_init_module+0x35/0x33b [ 16.688494] ? kasan_unpoison_shadow+0x31/0x40 [ 16.692968] ? kasan_kmalloc+0xa6/0xd0 [ 16.696743] ? do_init_module+0x35/0x33b [ 16.700694] ? kasan_unpoison_shadow+0x31/0x40 [ 16.705168] ? __asan_register_globals+0x82/0xa0 [ 16.709819] do_init_module+0xe7/0x33b [ 16.713597] load_module+0x4481/0x4ce0 [ 16.717397] ? module_frob_arch_sections+0x20/0x20 [ 16.722228] ? vfs_read+0x13b/0x190 [ 16.725742] ? kernel_read+0x74/0xa0 [ 16.729351] ? get_user_arg_ptr.isra.17+0x70/0x70 [ 16.734099] ? SYSC_finit_module+0x175/0x1b0 [ 16.738399] SYSC_finit_module+0x175/0x1b0 [ 16.742524] ? SYSC_init_module+0x1e0/0x1e0 [ 16.746741] ? __fget+0x157/0x240 [ 16.750090] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.754747] entry_SYSCALL_64_fastpath+0x23/0x9a [ 16.759397] RIP: 0033:0x7f8fbc837499 [ 16.762996] RSP: 002b:00007ffead76c138 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 16.770618] RAX: ffffffffffffffda RBX: 0000000000000012 RCX: 00007f8fbc837499 [ 16.777800] RDX: 0000000000000000 RSI: 000056484e67b080 RDI: 0000000000000012 [ 16.784979] RBP: 00007ffead76b140 R08: 0000000000000000 R09: 0000000000000021 [ 16.792164] R10: 0000000000000012 R11: 0000000000000246 R12: 000056484e67b460 [ 16.799345] R13: 00007ffead76b120 R14: 0000000000000005 R15: 0000000000000000 [ 16.808052] The buggy address belongs to the page: [ 16.812876] page:00000000dc4b8c1e count:0 mapcount:0 mapping: (null) index:0x0 [ 16.820934] flags: 0x17ffffc0000000() [ 16.824621] raw: 0017ffffc0000000 0000000000000000 0000000000000000 00000000ffffffff [ 16.832416] raw: ffffea000d85b3e0 ffffea000d85b3e0 0000000000000000 0000000000000000 [ 16.840208] page dumped because: kasan: bad access detected [ 16.847318] Memory state around the buggy address: [ 16.852143] ffff8803616cf400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 16.859427] ffff8803616cf480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 [ 16.866708] >ffff8803616cf500: f1 f1 04 f4 f4 f4 f3 f3 f3 f3 00 00 00 00 00 00 [ 16.873988] ^ [ 16.877770] ffff8803616cf580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 16.885042] ffff8803616cf600: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 [ 16.892312] ================================================================== Signed-off-by: Changbin Du <[email protected]> Signed-off-by: Zhenyu Wang <[email protected]>

When booting kernel with LOCKDEP option, below warning info was found: WARNING: possible recursive locking detected 4.19.0-rc7+ rib#14 Not tainted -------------------------------------------- swapper/0/1 is trying to acquire lock: 00000000dcfc0fc8 (&(&list->lock)->rlock#4){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline] 00000000dcfc0fc8 (&(&list->lock)->rlock#4){+...}, at: tipc_link_reset+0x125/0xdf0 net/tipc/link.c:850 but task is already holding lock: 00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline] 00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at: tipc_link_reset+0xfa/0xdf0 net/tipc/link.c:849 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&list->lock)->rlock#4); lock(&(&list->lock)->rlock#4); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by swapper/0/1: #0: 00000000f7539d34 (pernet_ops_rwsem){+.+.}, at: register_pernet_subsys+0x19/0x40 net/core/net_namespace.c:1051 rib#1: 00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline] rib#1: 00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at: tipc_link_reset+0xfa/0xdf0 net/tipc/link.c:849 stack backtrace: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc7+ rib#14 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1af/0x295 lib/dump_stack.c:113 print_deadlock_bug kernel/locking/lockdep.c:1759 [inline] check_deadlock kernel/locking/lockdep.c:1803 [inline] validate_chain kernel/locking/lockdep.c:2399 [inline] __lock_acquire+0xf1e/0x3c60 kernel/locking/lockdep.c:3411 lock_acquire+0x1db/0x520 kernel/locking/lockdep.c:3900 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168 spin_lock_bh include/linux/spinlock.h:334 [inline] tipc_link_reset+0x125/0xdf0 net/tipc/link.c:850 tipc_link_bc_create+0xb5/0x1f0 net/tipc/link.c:526 tipc_bcast_init+0x59b/0xab0 net/tipc/bcast.c:521 tipc_init_net+0x472/0x610 net/tipc/core.c:82 ops_init+0xf7/0x520 net/core/net_namespace.c:129 __register_pernet_operations net/core/net_namespace.c:940 [inline] register_pernet_operations+0x453/0xac0 net/core/net_namespace.c:1011 register_pernet_subsys+0x28/0x40 net/core/net_namespace.c:1052 tipc_init+0x83/0x104 net/tipc/core.c:140 do_one_initcall+0x109/0x70a init/main.c:885 do_initcall_level init/main.c:953 [inline] do_initcalls init/main.c:961 [inline] do_basic_setup init/main.c:979 [inline] kernel_init_freeable+0x4bd/0x57f init/main.c:1144 kernel_init+0x13/0x180 init/main.c:1063 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 The reason why the noise above was complained by LOCKDEP is because we nested to hold l->wakeupq.lock and l->inputq->lock in tipc_link_reset function. In fact it's unnecessary to move skb buffer from l->wakeupq queue to l->inputq queue while holding the two locks at the same time. Instead, we can move skb buffers in l->wakeupq queue to a temporary list first and then move the buffers of the temporary list to l->inputq queue, which is also safe for us. Fixes: 3f32d0b ("tipc: lock wakeup & inputq at tipc_link_reset()") Reported-by: Dmitry Vyukov <[email protected]> Signed-off-by: Ying Xue <[email protected]> Acked-by: Jon Maloy <[email protected]> Signed-off-by: David S. Miller <[email protected]>

There are actually two kinds of discard merge: - one is the normal discard merge, just like normal read/write request, and call it single-range discard - another is the multi-range discard, queue_max_discard_segments(rq->q) > 1 For the former case, queue_max_discard_segments(rq->q) is 1, and we should handle this kind of discard merge like the normal read/write request. This patch fixes the following kernel panic issue[1], which is caused by not removing the single-range discard request from elevator queue. Guangwu has one raid discard test case, in which this issue is a bit easier to trigger, and I verified that this patch can fix the kernel panic issue in Guangwu's test case. [1] kernel panic log from Jens's report BUG: unable to handle kernel NULL pointer dereference at 0000000000000148 PGD 0 P4D 0. Oops: 0000 [rib#1] SMP PTI CPU: 37 PID: 763 Comm: kworker/37:1H Not tainted \ 4.20.0-rc3-00649-ge64d9a554a91-dirty rib#14 Hardware name: Wiwynn \ Leopard-Orv2/Leopard-DDR BW, BIOS LBM08 03/03/2017 Workqueue: kblockd \ blk_mq_run_work_fn RIP: \ 0010:blk_mq_get_driver_tag+0x81/0x120 Code: 24 \ 10 48 89 7c 24 20 74 21 83 fa ff 0f 95 c0 48 8b 4c 24 28 65 48 33 0c 25 28 00 00 00 \ 0f 85 96 00 00 00 48 83 c4 30 5b 5d c3 <48> 8b 87 48 01 00 00 8b 40 04 39 43 20 72 37 \ f6 87 b0 00 00 00 02 RSP: 0018:ffffc90004aabd30 EFLAGS: 00010246 \ RAX: 0000000000000003 RBX: ffff888465ea1300 RCX: ffffc90004aabde8 RDX: 00000000ffffffff RSI: ffffc90004aabde8 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff888465ea1348 R09: 0000000000000000 R10: 0000000000001000 R11: 00000000ffffffff R12: ffff888465ea1300 R13: 0000000000000000 R14: ffff888465ea1348 R15: ffff888465d10000 FS: 0000000000000000(0000) GS:ffff88846f9c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000148 CR3: 000000000220a003 CR4: 00000000003606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: blk_mq_dispatch_rq_list+0xec/0x480 ? elv_rb_del+0x11/0x30 blk_mq_do_dispatch_sched+0x6e/0xf0 blk_mq_sched_dispatch_requests+0xfa/0x170 __blk_mq_run_hw_queue+0x5f/0xe0 process_one_work+0x154/0x350 worker_thread+0x46/0x3c0 kthread+0xf5/0x130 ? process_one_work+0x350/0x350 ? kthread_destroy_worker+0x50/0x50 ret_from_fork+0x1f/0x30 Modules linked in: sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel \ kvm switchtec irqbypass iTCO_wdt iTCO_vendor_support efivars cdc_ether usbnet mii \ cdc_acm i2c_i801 lpc_ich mfd_core ipmi_si ipmi_devintf ipmi_msghandler acpi_cpufreq \ button sch_fq_codel nfsd nfs_acl lockd grace auth_rpcgss oid_registry sunrpc nvme \ nvme_core fuse sg loop efivarfs autofs4 CR2: 0000000000000148 \ ---[ end trace 340a1fb996df1b9b ]--- RIP: 0010:blk_mq_get_driver_tag+0x81/0x120 Code: 24 10 48 89 7c 24 20 74 21 83 fa ff 0f 95 c0 48 8b 4c 24 28 65 48 33 0c 25 28 \ 00 00 00 0f 85 96 00 00 00 48 83 c4 30 5b 5d c3 <48> 8b 87 48 01 00 00 8b 40 04 39 43 \ 20 72 37 f6 87 b0 00 00 00 02 Fixes: 445251d ("blk-mq: fix discard merge with scheduler attached") Reported-by: Jens Axboe <[email protected]> Cc: Guangwu Zhang <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Jianchao Wang <[email protected]> Signed-off-by: Ming Lei <[email protected]> Signed-off-by: Jens Axboe <[email protected]>

Despite having stopped the parser, we still need to deinitialize it by calling strp_done so that it cancels its work. Otherwise the worker thread can run after we have freed the parser, and attempt to access its workqueue resulting in a use-after-free: ================================================================== BUG: KASAN: use-after-free in pwq_activate_delayed_work+0x1b/0x1d0 Read of size 8 at addr ffff888069975240 by task kworker/u2:2/93 CPU: 0 PID: 93 Comm: kworker/u2:2 Not tainted 5.0.0-rc2-00335-g28f9d1a3d4fe-dirty rib#14 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014 Workqueue: (null) (kstrp) Call Trace: print_address_description+0x6e/0x2b0 ? pwq_activate_delayed_work+0x1b/0x1d0 kasan_report+0xfd/0x177 ? pwq_activate_delayed_work+0x1b/0x1d0 ? pwq_activate_delayed_work+0x1b/0x1d0 pwq_activate_delayed_work+0x1b/0x1d0 ? process_one_work+0x4aa/0x660 pwq_dec_nr_in_flight+0x9b/0x100 worker_thread+0x82/0x680 ? process_one_work+0x660/0x660 kthread+0x1b9/0x1e0 ? __kthread_create_on_node+0x250/0x250 ret_from_fork+0x1f/0x30 Allocated by task 111: sk_psock_init+0x3c/0x1b0 sock_map_link.isra.2+0x103/0x4b0 sock_map_update_common+0x94/0x270 sock_map_update_elem+0x145/0x160 __se_sys_bpf+0x152e/0x1e10 do_syscall_64+0xb2/0x3e0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 112: kfree+0x7f/0x140 process_one_work+0x40b/0x660 worker_thread+0x82/0x680 kthread+0x1b9/0x1e0 ret_from_fork+0x1f/0x30 The buggy address belongs to the object at ffff888069975180 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 192 bytes inside of 512-byte region [ffff888069975180, ffff888069975380) The buggy address belongs to the page: page:ffffea0001a65d00 count:1 mapcount:0 mapping:ffff88806d401280 index:0x0 compound_mapcount: 0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 dead000000000100 dead000000000200 ffff88806d401280 raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888069975100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888069975180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888069975200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888069975280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888069975300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Reported-by: Marek Majkowski <[email protected]> Signed-off-by: Jakub Sitnicki <[email protected]> Link: https://lore.kernel.org/netdev/CAJPywTLwgXNEZ2dZVoa=udiZmtrWJ0q5SuBW64aYs0Y1khXX3A@mail.gmail.com Acked-by: Song Liu <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>

…r-free issue The evlist should be destroyed before the perf session. Detected with gcc's ASan: ================================================================= ==27350==ERROR: AddressSanitizer: heap-use-after-free on address 0x62b000002e38 at pc 0x5611da276999 bp 0x7ffce8f1d1a0 sp 0x7ffce8f1d190 WRITE of size 8 at 0x62b000002e38 thread T0 #0 0x5611da276998 in __list_del /home/work/linux/tools/include/linux/list.h:89 rib#1 0x5611da276d4a in __list_del_entry /home/work/linux/tools/include/linux/list.h:102 rib#2 0x5611da276e77 in list_del_init /home/work/linux/tools/include/linux/list.h:145 rib#3 0x5611da2781cd in thread__put util/thread.c:130 rib#4 0x5611da2cc0a8 in __thread__zput util/thread.h:68 rib#5 0x5611da2d2dcb in hist_entry__delete util/hist.c:1148 rib#6 0x5611da2cdf91 in hists__delete_entry util/hist.c:337 rib#7 0x5611da2ce19e in hists__delete_entries util/hist.c:365 rib#8 0x5611da2db2ab in hists__delete_all_entries util/hist.c:2639 rib#9 0x5611da2db325 in hists_evsel__exit util/hist.c:2651 rib#10 0x5611da1c5352 in perf_evsel__exit util/evsel.c:1304 rib#11 0x5611da1c5390 in perf_evsel__delete util/evsel.c:1309 rib#12 0x5611da1b35f0 in perf_evlist__purge util/evlist.c:124 rib#13 0x5611da1b38e2 in perf_evlist__delete util/evlist.c:148 rib#14 0x5611da069781 in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1645 rib#15 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 rib#16 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 rib#17 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 rib#18 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 rib#19 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) rib#20 0x5611d9ff35c9 in _start (/home/work/linux/tools/perf/perf+0x3e95c9) 0x62b000002e38 is located 11320 bytes inside of 27448-byte region [0x62b000000200,0x62b000006d38) freed by thread T0 here: #0 0x7fdccb04ab70 in free (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedb70) rib#1 0x5611da260df4 in perf_session__delete util/session.c:201 rib#2 0x5611da063de5 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1300 rib#3 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642 rib#4 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 rib#5 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 rib#6 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 rib#7 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 rib#8 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) previously allocated by thread T0 here: #0 0x7fdccb04b138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138) rib#1 0x5611da26010c in zalloc util/util.h:23 rib#2 0x5611da260824 in perf_session__new util/session.c:118 rib#3 0x5611da0633a6 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1192 rib#4 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642 rib#5 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 rib#6 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 rib#7 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 rib#8 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 rib#9 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) SUMMARY: AddressSanitizer: heap-use-after-free /home/work/linux/tools/include/linux/list.h:89 in __list_del Shadow bytes around the buggy address: 0x0c567fff8570: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8580: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8590: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85a0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85b0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd =>0x0c567fff85c0: fd fd fd fd fd fd fd[fd]fd fd fd fd fd fd fd fd 0x0c567fff85d0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85e0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85f0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8600: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8610: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb ==27350==ABORTING Signed-off-by: Changbin Du <[email protected]> Reviewed-by: Jiri Olsa <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt (VMware) <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

Using gcc's ASan, Changbin reports: ================================================================= ==7494==ERROR: LeakSanitizer: detected memory leaks Direct leak of 48 byte(s) in 1 object(s) allocated from: #0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138) rib#1 0x5625e5330a5e in zalloc util/util.h:23 rib#2 0x5625e5330a9b in perf_counts__new util/counts.c:10 rib#3 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47 rib#4 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505 rib#5 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347 rib#6 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47 rib#7 0x5625e51528e6 in run_test tests/builtin-test.c:358 rib#8 0x5625e5152baf in test_and_print tests/builtin-test.c:388 rib#9 0x5625e51543fe in __cmd_test tests/builtin-test.c:583 rib#10 0x5625e515572f in cmd_test tests/builtin-test.c:722 rib#11 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 rib#12 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 rib#13 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 rib#14 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520 rib#15 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) Indirect leak of 72 byte(s) in 1 object(s) allocated from: #0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138) rib#1 0x5625e532560d in zalloc util/util.h:23 rib#2 0x5625e532566b in xyarray__new util/xyarray.c:10 rib#3 0x5625e5330aba in perf_counts__new util/counts.c:15 rib#4 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47 rib#5 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505 rib#6 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347 rib#7 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47 rib#8 0x5625e51528e6 in run_test tests/builtin-test.c:358 rib#9 0x5625e5152baf in test_and_print tests/builtin-test.c:388 rib#10 0x5625e51543fe in __cmd_test tests/builtin-test.c:583 rib#11 0x5625e515572f in cmd_test tests/builtin-test.c:722 rib#12 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 rib#13 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 rib#14 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 rib#15 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520 rib#16 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) His patch took care of evsel->prev_raw_counts, but the above backtraces are about evsel->counts, so fix that instead. Reported-by: Changbin Du <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt (VMware) <[email protected]> Link: https://lkml.kernel.org/n/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

…_event_on_all_cpus test ================================================================= ==7497==ERROR: LeakSanitizer: detected memory leaks Direct leak of 40 byte(s) in 1 object(s) allocated from: #0 0x7f0333a88f30 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf30) rib#1 0x5625e5326213 in cpu_map__trim_new util/cpumap.c:45 rib#2 0x5625e5326703 in cpu_map__read util/cpumap.c:103 rib#3 0x5625e53267ef in cpu_map__read_all_cpu_map util/cpumap.c:120 rib#4 0x5625e5326915 in cpu_map__new util/cpumap.c:135 rib#5 0x5625e517b355 in test__openat_syscall_event_on_all_cpus tests/openat-syscall-all-cpus.c:36 rib#6 0x5625e51528e6 in run_test tests/builtin-test.c:358 rib#7 0x5625e5152baf in test_and_print tests/builtin-test.c:388 rib#8 0x5625e51543fe in __cmd_test tests/builtin-test.c:583 rib#9 0x5625e515572f in cmd_test tests/builtin-test.c:722 rib#10 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 rib#11 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 rib#12 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 rib#13 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520 rib#14 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) Signed-off-by: Changbin Du <[email protected]> Reviewed-by: Jiri Olsa <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt (VMware) <[email protected]> Fixes: f30a79b ("perf tools: Add reference counting for cpu_map object") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

By calling maps__insert() we assume to get 2 references on the map, which we relese within maps__remove call. However if there's already same map name, we currently don't bump the reference and can crash, like: Program received signal SIGABRT, Aborted. 0x00007ffff75e60f5 in raise () from /lib64/libc.so.6 (gdb) bt #0 0x00007ffff75e60f5 in raise () from /lib64/libc.so.6 rib#1 0x00007ffff75d0895 in abort () from /lib64/libc.so.6 rib#2 0x00007ffff75d0769 in __assert_fail_base.cold () from /lib64/libc.so.6 rib#3 0x00007ffff75de596 in __assert_fail () from /lib64/libc.so.6 rib#4 0x00000000004fc006 in refcount_sub_and_test (i=1, r=0x1224e88) at tools/include/linux/refcount.h:131 rib#5 refcount_dec_and_test (r=0x1224e88) at tools/include/linux/refcount.h:148 rib#6 map__put (map=0x1224df0) at util/map.c:299 rib#7 0x00000000004fdb95 in __maps__remove (map=0x1224df0, maps=0xb17d80) at util/map.c:953 rib#8 maps__remove (maps=0xb17d80, map=0x1224df0) at util/map.c:959 rib#9 0x00000000004f7d8a in map_groups__remove (map=<optimized out>, mg=<optimized out>) at util/map_groups.h:65 rib#10 machine__process_ksymbol_unregister (sample=<optimized out>, event=0x7ffff7279670, machine=<optimized out>) at util/machine.c:728 rib#11 machine__process_ksymbol (machine=<optimized out>, event=0x7ffff7279670, sample=<optimized out>) at util/machine.c:741 rib#12 0x00000000004fffbb in perf_session__deliver_event (session=0xb11390, event=0x7ffff7279670, tool=0x7fffffffc7b0, file_offset=13936) at util/session.c:1362 rib#13 0x00000000005039bb in do_flush (show_progress=false, oe=0xb17e80) at util/ordered-events.c:243 rib#14 __ordered_events__flush (oe=0xb17e80, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:322 rib#15 0x00000000005005e4 in perf_session__process_user_event (session=session@entry=0xb11390, event=event@entry=0x7ffff72a4af8, ... Add the map to the list and getting the reference event if we find the map with same name. Signed-off-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: Eric Saint-Etienne <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Song Liu <[email protected]> Fixes: 1e62856 ("perf symbols: Fix slowness due to -ffunction-section") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

Backlog work for psock (sk_psock_backlog) might sleep while waiting for memory to free up when sending packets. However, while sleeping the socket may be closed and removed from the map by the user space side. This breaks an assumption in sk_stream_wait_memory, which expects the wait queue to be still there when it wakes up resulting in a use-after-free shown below. To fix his mark sendmsg as MSG_DONTWAIT to avoid the sleep altogether. We already set the flag for the sendpage case but we missed the case were sendmsg is used. Sockmap is currently the only user of skb_send_sock_locked() so only the sockmap paths should be impacted. ================================================================== BUG: KASAN: use-after-free in remove_wait_queue+0x31/0x70 Write of size 8 at addr ffff888069a0c4e8 by task kworker/0:2/110 CPU: 0 PID: 110 Comm: kworker/0:2 Not tainted 5.0.0-rc2-00335-g28f9d1a3d4fe-dirty rib#14 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014 Workqueue: events sk_psock_backlog Call Trace: print_address_description+0x6e/0x2b0 ? remove_wait_queue+0x31/0x70 kasan_report+0xfd/0x177 ? remove_wait_queue+0x31/0x70 ? remove_wait_queue+0x31/0x70 remove_wait_queue+0x31/0x70 sk_stream_wait_memory+0x4dd/0x5f0 ? sk_stream_wait_close+0x1b0/0x1b0 ? wait_woken+0xc0/0xc0 ? tcp_current_mss+0xc5/0x110 tcp_sendmsg_locked+0x634/0x15d0 ? tcp_set_state+0x2e0/0x2e0 ? __kasan_slab_free+0x1d1/0x230 ? kmem_cache_free+0x70/0x140 ? sk_psock_backlog+0x40c/0x4b0 ? process_one_work+0x40b/0x660 ? worker_thread+0x82/0x680 ? kthread+0x1b9/0x1e0 ? ret_from_fork+0x1f/0x30 ? check_preempt_curr+0xaf/0x130 ? iov_iter_kvec+0x5f/0x70 ? kernel_sendmsg_locked+0xa0/0xe0 skb_send_sock_locked+0x273/0x3c0 ? skb_splice_bits+0x180/0x180 ? start_thread+0xe0/0xe0 ? update_min_vruntime.constprop.27+0x88/0xc0 sk_psock_backlog+0xb3/0x4b0 ? strscpy+0xbf/0x1e0 process_one_work+0x40b/0x660 worker_thread+0x82/0x680 ? process_one_work+0x660/0x660 kthread+0x1b9/0x1e0 ? __kthread_create_on_node+0x250/0x250 ret_from_fork+0x1f/0x30 Fixes: 20bf50d ("skbuff: Function to send an skbuf on a socket") Reported-by: Jakub Sitnicki <[email protected]> Tested-by: Jakub Sitnicki <[email protected]> Signed-off-by: John Fastabend <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>

This reverts commit 3df85a1. The reverted commit says "It's possible to release the node ID immediately when fwnode_remove_software_node() is called, no need to wait for software_node_release() with that." However, releasing the node ID before waiting for software_node_release() to be called causes the node ID to be released before the kobject and the underlying sysfs entry; this means there is a period of time where a sysfs entry exists that is associated with an unallocated node ID. Once consequence of this is that there is a race condition where it is possible to call fwnode_create_software_node() with no parent node specified (NULL) and have it fail with -EEXIST because the node ID that was assigned is still associated with a stale sysfs entry that hasn't been cleaned up yet. Although it is difficult to reproduce this race condition under normal conditions, it can be deterministically reproduced with the following minconfig on UML: CONFIG_KUNIT_DRIVER_PE_TEST=y CONFIG_DEBUG_KERNEL=y CONFIG_DEBUG_OBJECTS=y CONFIG_DEBUG_OBJECTS_TIMERS=y CONFIG_DEBUG_KOBJECT_RELEASE=y CONFIG_KUNIT=y Running the tests with this configuration causes the following failure: <snip> kobject: 'node0' ((____ptrval____)): kobject_release, parent (____ptrval____) (delayed 400) ok 1 - pe_test_uints sysfs: cannot create duplicate filename '/kernel/software_nodes/node0' CPU: 0 PID: 28 Comm: kunit_try_catch Not tainted 5.6.0-rc3-next-20200227 rib#14 <snip> kobject_add_internal failed for node0 with -EEXIST, don't try to register things with the same name in the same directory. kobject: 'node0' ((____ptrval____)): kobject_release, parent (____ptrval____) (delayed 100) # pe_test_uint_arrays: ASSERTION FAILED at drivers/base/test/property-entry-test.c:123 Expected node is not error, but is: -17 not ok 2 - pe_test_uint_arrays <snip> Reported-by: Heidi Fahim <[email protected]> Signed-off-by: Brendan Higgins <[email protected]> Reviewed-by: Heikki Krogerus <[email protected]> Cc: 5.3+ <[email protected]> # 5.3+ Signed-off-by: Rafael J. Wysocki <[email protected]>

rib added the bug label Mar 2, 2016

rib closed this as completed Mar 24, 2016

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Check the return value of enable_metric_set #14

Check the return value of enable_metric_set #14

matt-auld commented Feb 15, 2016

rib commented Mar 24, 2016

Check the return value of enable_metric_set #14

Check the return value of enable_metric_set #14

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matt-auld commented Feb 15, 2016

rib commented Mar 24, 2016