Bug 275920 - Kernel crash in sys/netlink/route/iface.c:124
Summary: Kernel crash in sys/netlink/route/iface.c:124
Status: New
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: 14.0-RELEASE
Hardware: arm64 Any
: --- Affects Some People
Assignee: freebsd-net (Nobody)
URL:
Keywords: crash
Depends on:
Blocks:
 
Reported: 2023-12-25 04:07 UTC by Mike Cui
Modified: 2024-10-08 07:16 UTC (History)
9 users (show)

See Also:


Attachments
kernel crashdump (55.83 KB, text/plain)
2023-12-25 04:07 UTC, Mike Cui
no flags Details

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Description Mike Cui 2023-12-25 04:07:14 UTC
Created attachment 247235 [details]
kernel crashdump

I have an espressobin v7 which was running fine on 13.2-RELEASE. However, after upgrading to 14.0-RELEASE, the kernel crashes with vm_fault immediately after loading the e6000sw module.

Attached is the full kernel crash dump core.txt file.
Comment 1 Mike Cui 2023-12-25 04:26:43 UTC
Presumably the crash happened sys/netlink/route/iface.c:124, in function get_operstate_ether() which calls if_ioctl(), and ifp->if_ioctl is NULL for some reason.

It also appears that NETLINK subsystem was added in 13.2, but NETLINK is not included in the base kernel in 13.2, but it is in 14.0. Is NETLINK required in 14.0? Can just compile out of the kernel myself?
Comment 2 Kristof Provost freebsd_committer freebsd_triage 2023-12-25 09:44:27 UTC
That's interesting. The cause is fairly obvious. e6000sw creates struct ifnets that don't have an ioctl handler, and that's triggering this crash.

The following is probably the best fix, assuming that the ioctl-less e6000sw ifnet is intentional:

diff --git a/sys/net/if.c b/sys/net/if.c
index 9f44223af0dd..c3c27fbf678f 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -4871,6 +4871,9 @@ if_resolvemulti(if_t ifp, struct sockaddr **srcs, struct sockaddr *dst)
 int
 if_ioctl(if_t ifp, u_long cmd, void *data)
 {
+       if (ifp->if_ioctl == NULL)
+               return (EOPNOTSUPP);
+
        return (ifp->if_ioctl(ifp, cmd, data));
 }
Comment 3 Gleb Smirnoff freebsd_committer freebsd_triage 2023-12-25 16:54:03 UTC
On 2023-12-25 09:44:27 UTC, kp@freebsd.org wrote:
> That's interesting. The cause is fairly obvious. e6000sw creates struct ifnets
> that don't have an ioctl handler, and that's triggering this crash.

Well, without Netlink, there were always ways to call if_ioctl() and
that would crash on stable/13.

Mike, can you please provide full trace of the crash? Can you please point
me to the sources of the e6000sw?
Comment 4 Kristof Provost freebsd_committer freebsd_triage 2023-12-25 17:18:12 UTC
That code lives in sys/dev/etherswitch/e6000sw/e6000sw.c

It creates a struct ifnet for each port in e6000sw_attach() / e6000sw_init_interface(). It never actually attached that ifnet though. I believe it's only created so e6000sw can call into the mii code, which is also how I think we eventually end up in the panicing stack. There's a link state event, which calls do_link_state_change() -> rtnl_handle_ifevent() -> dump_iface() -> get_operstate() -> get_operstate_ether(). That wants to know if the link is up or down, so it tries to ioctl(SIOCGIFMEDIA). Which doesn't go well if if_ioctl is NULL.

Here's the relevant bit of backtrace: 

#7  0x0000000000000000 in ?? ()
#8  0xffff0000006f87f4 in get_operstate_ether (ifp=0xffffa00002f7d000, 
    pstate=<optimized out>) at /usr/src/sys/netlink/route/iface.c:124
#9  get_operstate (ifp=0xffffa00002f7d000, pstate=<optimized out>)
    at /usr/src/sys/netlink/route/iface.c:181
#10 dump_iface (nw=nw@entry=0xffff0000877e0780, 
    ifp=ifp@entry=0xffffa00002f7d000, hdr=hdr@entry=0xffff0000877e07c0, 
    if_flags_mask=if_flags_mask@entry=0)
    at /usr/src/sys/netlink/route/iface.c:310
#11 0xffff0000006f80cc in rtnl_handle_ifevent (ifp=0xffffa00002f7d000, 
    nlmsg_type=<optimized out>, if_flags_mask=0)
    at /usr/src/sys/netlink/route/iface.c:1411
#12 0xffff0000005f9cb8 in do_link_state_change (arg=0xffffa00002f7d000, 
    pending=1) at /usr/src/sys/net/if.c:2181
#13 0xffff000000525bf0 in taskqueue_run_locked (
    queue=queue@entry=0xffffa0000136d300)
    at /usr/src/sys/kern/subr_taskqueue.c:512
#14 0xffff00000052594c in taskqueue_run (queue=0xffffa0000136d300)
    at /usr/src/sys/kern/subr_taskqueue.c:527
Comment 5 Mike Cui 2024-05-05 02:58:16 UTC
Any chance we can get this fixed for 14.1?

It would be nice if 14.1 worked out of the box without having to cross compile my own custom kernel.
Comment 6 commit-hook freebsd_committer freebsd_triage 2024-05-06 13:25:27 UTC
A commit in branch main references this bug:

URL: https://cgit.FreeBSD.org/src/commit/?id=43387b4e574043b78a58c8bcb7575161b055fce1

commit 43387b4e574043b78a58c8bcb7575161b055fce1
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2024-05-06 09:39:08 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2024-05-06 09:39:08 +0000

    if: guard against if_ioctl being NULL

    There are situations where an struct ifnet has a NULL if_ioctl pointer.

    For example, e6000sw creates such struct ifnets for each of its ports so it can
    call into the MII code.

    If there is then a link state event this calls do_link_state_change()
    -> rtnl_handle_ifevent() -> dump_iface() -> get_operstate() ->
    get_operstate_ether(). That wants to know if the link is up or down, so it tries
    to ioctl(SIOCGIFMEDIA), which doesn't go well if if_ioctl is NULL.

    Guard against this, and return EOPNOTSUPP.

    PR:             275920
    MFC ater:       3 days
    Sponsored by:   Rubicon Communications, LLC ("Netgate")

 sys/net/if.c | 3 +++
 1 file changed, 3 insertions(+)
Comment 7 commit-hook freebsd_committer freebsd_triage 2024-05-12 16:13:15 UTC
A commit in branch stable/14 references this bug:

URL: https://cgit.FreeBSD.org/src/commit/?id=9a8a26aefb366ef6f497d48547a1562a1de566c1

commit 9a8a26aefb366ef6f497d48547a1562a1de566c1
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2024-05-06 09:39:08 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2024-05-12 16:12:04 +0000

    if: guard against if_ioctl being NULL

    There are situations where an struct ifnet has a NULL if_ioctl pointer.

    For example, e6000sw creates such struct ifnets for each of its ports so it can
    call into the MII code.

    If there is then a link state event this calls do_link_state_change()
    -> rtnl_handle_ifevent() -> dump_iface() -> get_operstate() ->
    get_operstate_ether(). That wants to know if the link is up or down, so it tries
    to ioctl(SIOCGIFMEDIA), which doesn't go well if if_ioctl is NULL.

    Guard against this, and return EOPNOTSUPP.

    PR:             275920
    MFC ater:       3 days
    Sponsored by:   Rubicon Communications, LLC ("Netgate")

    (cherry picked from commit 43387b4e574043b78a58c8bcb7575161b055fce1)

 sys/net/if.c | 3 +++
 1 file changed, 3 insertions(+)
Comment 8 Mike Cui 2024-05-17 17:25:45 UTC
Gentle reminder: can this be cherry-picked to releng/14.1?
Comment 9 commit-hook freebsd_committer freebsd_triage 2024-05-20 07:39:30 UTC
A commit in branch releng/14.1 references this bug:

URL: https://cgit.FreeBSD.org/src/commit/?id=fecd303882565954f58d984e4a13735e080b5263

commit fecd303882565954f58d984e4a13735e080b5263
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2024-05-06 09:39:08 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2024-05-20 07:38:40 +0000

    if: guard against if_ioctl being NULL

    There are situations where an struct ifnet has a NULL if_ioctl pointer.

    For example, e6000sw creates such struct ifnets for each of its ports so it can
    call into the MII code.

    If there is then a link state event this calls do_link_state_change()
    -> rtnl_handle_ifevent() -> dump_iface() -> get_operstate() ->
    get_operstate_ether(). That wants to know if the link is up or down, so it tries
    to ioctl(SIOCGIFMEDIA), which doesn't go well if if_ioctl is NULL.

    Guard against this, and return EOPNOTSUPP.

    PR:             275920
    MFC ater:       3 days
    Approved by:    re (cperciva)
    Sponsored by:   Rubicon Communications, LLC ("Netgate")

    (cherry picked from commit 43387b4e574043b78a58c8bcb7575161b055fce1)
    (cherry picked from commit 9a8a26aefb366ef6f497d48547a1562a1de566c1)

 sys/net/if.c | 3 +++
 1 file changed, 3 insertions(+)
Comment 10 LekKit 2024-06-19 21:34:54 UTC
This also affects if_re driver with Realtek RTL8169 NIC in some cases. Reproducible on FreeBSD 14.1 and 15.0-CURRENT

My RVVM virtual machine emulates rtl8169 and triggers this bug (apparently):

https://github.com/LekKit/RVVM/issues/131

KDB: stack backtrace:
db_trace_self() at db_trace_self
db_trace_self_wrapper() at db_trace_self_wrapper+0x36
kdb_backtrace() at kdb_backtrace+0x2c
vpanic() at vpanic+0x122
panic() at panic+0x26
page_fault_handler() at page_fault_handler+0x22a
do_trap_supervisor() at do_trap_supervisor+0x6c
cpu_exception_handler_supervisor() at cpu_exception_handler_supervisor+0x74
--- exception 12, tval = 0
(null)() at 0
if_ioctl() at if_ioctl+0xc
dump_iface() at dump_iface+0x10e
rtnl_handle_ifevent() at rtnl_handle_ifevent+0x74
rtnl_handle_ifattach() at rtnl_handle_ifattach+0x48
if_attach_internal() at if_attach_internal+0x33a
if_attach() at if_attach+0xe
ether_ifattach() at ether_ifattach+0x32
.Lpcrel_hi106() at .Lpcrel_hi106+0x46
device_attach() at device_attach+0x36a
device_probe_and_attach() at device_probe_and_attach+0x72
pci_driver_added() at pci_driver_added+0x102
devclass_driver_added() at devclass_driver_added+0x34
devclass_add_driver() at devclass_add_driver+0xfc
driver_module_handler() at driver_module_handler+0x6a
module_register_init() at module_register_init+0xa8
linker_load_module() at linker_load_module+0x9e6
kern_kldload() at kern_kldload+0x14e
sys_kldload() at sys_kldload+0x54
do_trap_user() at do_trap_user+0x1de
cpu_exception_handler_user() at cpu_exception_handler_user+0x72
--- syscall (304, FreeBSD ELF64, kldload)
Comment 11 unspam 2024-08-02 11:35:14 UTC
Same issue here with 15-Current and 14.1 stable
Comment 12 LekKit 2024-10-08 07:09:41 UTC
Still happening in both 15-CURRENT and 14.1-STABLE

root@freebsd:~ # kldload if_re
re0: <RealTek 8169/8169S/8169SB(L)/8110S/8110SB(L) Gigabit Ethernet> mem 0x40000000-0x400000ff irq 9 at device 1.0 on pci0
re0: Chip rev. 0x00800000
re0: MAC rev. 0x00000000
   t[0]: 0x0000000000000800
   t[1]: 0xffffffc071c0b26c
   t[2]: 0x49f17f2d48bb1c18
   t[3]: 0xffffffc0003f699c
   t[4]: 0xda0f930be87ea53e
   t[5]: 0x9b63889a118d9c5c
   t[6]: 0x7ffe55743bd38475
   s[0]: 0xffffffc050c9a280
   s[1]: 0xffffffd00264ea80
   s[2]: 0xffffffc050c9a2b8
   s[3]: 0x0000000000000000
   s[4]: 0xffffffd002498810
   s[5]: 0xffffffc050c9a358
   s[6]: 0xffffffc0009add18
   s[7]: 0xffffffc0007f2b62
   s[8]: 0xffffffc068700138
   s[9]: 0xffffffc068703130
  s[10]: 0xffffffc000717948
  s[11]: 0x0000000000000801
   a[0]: 0xffffffd00265e000
   a[1]: 0xffffffc050c9a2b8
   a[2]: 0xffffffd00264ea80
   a[3]: 0x0000000000000000
   a[4]: 0x00000000c0306938
   a[5]: 0x0000000000000010
   a[6]: 0x0000000000000020
   a[7]: 0x0000000000000016
     ra: 0xffffffc0003f6a8c
     sp: 0xffffffc050c9a250
     gp: 0xffffffc0007f1520
     tp: 0xffffffc0009c0700
   sepc: 0x0000000000000000
sstatus: 0x0000000200000120
stval  : 0x0000000000000000
panic: Fatal page fault at 0: 0
cpuid = 0
time = 1728370984
KDB: stack backtrace:
#0 0xffffffc00033755e at kdb_backtrace+0x4a
#1 0xffffffc0002f2878 at vpanic+0x10c
#2 0xffffffc0002f2768 at panic+0x26
#3 0xffffffc0005a171c at page_fault_handler+0x210
#4 0xffffffc0005a0e50 at do_trap_supervisor+0x52
#5 0xffffffc000591344 at cpu_exception_handler_supervisor+0x74
#6 0xffffffc0003edd5a at if_ioctl+0xc
#7 0xffffffc0004aac66 at dump_iface+0x130
#8 0xffffffc0004aa5da at rtnl_handle_ifevent+0x7c
#9 0xffffffc0004aa8e0 at rtnl_handle_ifattach+0x48
#10 0xffffffc0003e79a4 at if_attach_internal+0x36c
#11 0xffffffc0003e762c at if_attach+0xe
#12 0xffffffc0003f20f6 at ether_ifattach+0x34
#13 0xffffffc071c068e2 at .Lpcrel_hi95+0x46
#14 0xffffffc0003281ca at device_attach+0x36a
#15 0xffffffc000327e44 at device_probe_and_attach+0x3e
#16 0xffffffc000125f94 at pci_driver_added+0x102
#17 0xffffffc000325bfc at devclass_driver_added+0x34
Comment 13 LekKit 2024-10-08 07:16:27 UTC
FreeBSD 15-CURRENT backtrace

root@freebsd:~ # kldload if_re
re0: <RealTek 8169/8169S/8169SB(L)/8110S/8110SB(L) Gigabit Ethernet> mem 0x40000000-0x400000ff irq 9 at device 1.0 on pci0
re0: Chip rev. 0x00800000
re0: MAC rev. 0x00000000
   t[0]: 0x0000000000000000
   t[1]: 0xffffffc07560b49c (.Lpcrel_hi235 + 0x4a2)
   t[2]: 0x0000000000010000
   t[3]: 0xffffffc0004232ba (ifmedia_ioctl)
   t[4]: 0x744380940d76cf29
   t[5]: 0x35930f09d23e5346
   t[6]: 0x4134e5b735e0dc80
   s[0]: 0xffffffc054f232b0 ($d.1 + 0x51ee95a8)
   s[1]: 0xffffffd000b43900
   s[2]: 0xffffffc054f232f0 ($d.1 + 0x51ee95e8)
   s[3]: 0x0000000000000000
   s[4]: 0xffffffd0571ce000
   s[5]: 0xffffffd02c09302c
   s[6]: 0xffffffc000a6bd40 (__stack_chk_guard)
   s[7]: 0xffffffc0008a8666 ($d.0 + 0xe)
   s[8]: 0xffffffc07557c138 ($d.1 + 0x72542430)
   s[9]: 0xffffffc07557f130 ($d.1 + 0x72545428)
  s[10]: 0xffffffc0007a1350 (pci_find_cap_desc)
  s[11]: 0x0000000000000801
   a[0]: 0xffffffd0571ce000
   a[1]: 0xffffffc054f232f0 ($d.1 + 0x51ee95e8)
   a[2]: 0xffffffd000b43900
   a[3]: 0x0000000000000000
   a[4]: 0x00000000c0306938
   a[5]: 0x0000000000000010
   a[6]: 0xffffffd02c09301c
   a[7]: 0x0000000000000016
     ra: 0xffffffc0004233aa (ifmedia_ioctl + 0xf0)
     sp: 0xffffffc054f23280 ($d.1 + 0x51ee9578)
     gp: 0xffffffc0008a7730 (__global_pointer$)
     tp: 0xffffffc000b2ca80 (__pcpu)
   sepc: 0x0000000000000000
sstatus: 0x0000000200000120
stval  : 0x0000000000000000
panic: Fatal page fault at 0: 0
cpuid = 0
time = 1728371624
KDB: stack backtrace:
db_trace_self() at db_trace_self
db_trace_self_wrapper() at db_trace_self_wrapper+0x36
kdb_backtrace() at kdb_backtrace+0x2c
vpanic() at vpanic+0x122
panic() at panic+0x26
page_fault_handler() at page_fault_handler+0x22a
do_trap_supervisor() at do_trap_supervisor+0x6c
cpu_exception_handler_supervisor() at cpu_exception_handler_supervisor+0x74
--- exception 12, tval = 0
(null)() at 0
if_ioctl() at if_ioctl+0xc
dump_iface() at dump_iface+0x10e
rtnl_handle_ifevent() at rtnl_handle_ifevent+0x74
rtnl_handle_ifattach() at rtnl_handle_ifattach+0x48
if_attach_internal() at if_attach_internal+0x33a
if_attach() at if_attach+0xe
ether_ifattach() at ether_ifattach+0x32
.Lpcrel_hi105() at .Lpcrel_hi105+0x46
device_attach() at device_attach+0x36a
device_probe_and_attach() at device_probe_and_attach+0x72
pci_driver_added() at pci_driver_added+0x102
devclass_driver_added() at devclass_driver_added+0x34
devclass_add_driver() at devclass_add_driver+0xfc
driver_module_handler() at driver_module_handler+0x6a
module_register_init() at module_register_init+0xa8
linker_load_module() at linker_load_module+0x9e6
kern_kldload() at kern_kldload+0x14e
sys_kldload() at sys_kldload+0x54
do_trap_user() at do_trap_user+0x1e0
cpu_exception_handler_user() at cpu_exception_handler_user+0x72
--- syscall (304, FreeBSD ELF64, kldload)