Xin Long fbd019737d sctp: avoid running the sctp state machine recursively ... Ying triggered a call trace when doing an asconf testing: BUG: scheduling while atomic: swapper/12/0/0x10000100 Call Trace: <IRQ> [<ffffffffa4375904>] dump_stack+0x19/0x1b [<ffffffffa436fcaf>] __schedule_bug+0x64/0x72 [<ffffffffa437b93a>] __schedule+0x9ba/0xa00 [<ffffffffa3cd5326>] __cond_resched+0x26/0x30 [<ffffffffa437bc4a>] _cond_resched+0x3a/0x50 [<ffffffffa3e22be8>] kmem_cache_alloc_node+0x38/0x200 [<ffffffffa423512d>] __alloc_skb+0x5d/0x2d0 [<ffffffffc0995320>] sctp_packet_transmit+0x610/0xa20 [sctp] [<ffffffffc098510e>] sctp_outq_flush+0x2ce/0xc00 [sctp] [<ffffffffc098646c>] sctp_outq_uncork+0x1c/0x20 [sctp] [<ffffffffc0977338>] sctp_cmd_interpreter.isra.22+0xc8/0x1460 [sctp] [<ffffffffc0976ad1>] sctp_do_sm+0xe1/0x350 [sctp] [<ffffffffc099443d>] sctp_primitive_ASCONF+0x3d/0x50 [sctp] [<ffffffffc0977384>] sctp_cmd_interpreter.isra.22+0x114/0x1460 [sctp] [<ffffffffc0976ad1>] sctp_do_sm+0xe1/0x350 [sctp] [<ffffffffc097b3a4>] sctp_assoc_bh_rcv+0xf4/0x1b0 [sctp] [<ffffffffc09840f1>] sctp_inq_push+0x51/0x70 [sctp] [<ffffffffc099732b>] sctp_rcv+0xa8b/0xbd0 [sctp] As it shows, the first sctp_do_sm() running under atomic context (NET_RX softirq) invoked sctp_primitive_ASCONF() that uses GFP_KERNEL flag later, and this flag is supposed to be used in non-atomic context only. Besides, sctp_do_sm() was called recursively, which is not expected. Vlad tried to fix this recursive call in Commit c078669340 ("sctp: Fix oops when sending queued ASCONF chunks") by introducing a new command SCTP_CMD_SEND_NEXT_ASCONF. But it didn't work as this command is still used in the first sctp_do_sm() call, and sctp_primitive_ASCONF() will be called in this command again. To avoid calling sctp_do_sm() recursively, we send the next queued ASCONF not by sctp_primitive_ASCONF(), but by sctp_sf_do_prm_asconf() in the 1st sctp_do_sm() directly. Reported-by: Ying Xu <yinxu@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2019-05-01 09:18:57 -04:00
..
acpi	ACPI: use different default debug value than ACPICA	2019-03-25 10:45:59 +01:00
asm-generic	syscalls: Remove start and number from syscall_set_arguments() args	2019-04-05 09:27:23 -04:00
clocksource
crypto
drm	drm/atomic-helper: Make atomic_enable/disable crtc callbacks optional	2019-03-29 11:56:52 +01:00
dt-bindings	dt-bindings: clock: sifive: add FU540-C000 PRCI clock constants	2019-04-09 20:36:40 -07:00
keys	KEYS: trusted: fix -Wvarags warning	2019-04-08 15:58:54 -07:00
kvm	ARM: some cleanups, direct physical timer assignment, cache sanitization	2019-03-15 15:00:28 -07:00
linux	Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf	2019-04-26 01:54:42 -04:00
math-emu
media
memory
misc	auxdisplay: charlcd: Introduce charlcd_free() helper	2019-03-17 08:48:16 +01:00
net	sctp: avoid running the sctp state machine recursively	2019-05-01 09:18:57 -04:00
pcmcia
ras
rdma
scsi
soc	IOMMU Updates for Linux v5.1	2019-03-10 12:29:52 -07:00
sound	ASoC: core: conditionally increase module refcount on component open	2019-04-08 14:15:44 +07:00
target
trace	syscalls: Remove start and number from syscall_get_arguments() args	2019-04-05 09:26:43 -04:00
uapi	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input	2019-04-19 10:28:27 -07:00
video	media updates for v5.1-rc1	2019-03-09 14:45:54 -08:00
xen