Yang Yingliang f4c23a140d serial: 8250: fix null-ptr-deref in serial8250_start_tx() ... I got null-ptr-deref in serial8250_start_tx(): [ 78.114630] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 78.123778] Mem abort info: [ 78.126560] ESR = 0x86000007 [ 78.129603] EC = 0x21: IABT (current EL), IL = 32 bits [ 78.134891] SET = 0, FnV = 0 [ 78.137933] EA = 0, S1PTW = 0 [ 78.141064] user pgtable: 64k pages, 48-bit VAs, pgdp=00000027d41a8600 [ 78.147562] [0000000000000000] pgd=00000027893f0003, p4d=00000027893f0003, pud=00000027893f0003, pmd=00000027c9a20003, pte=0000000000000000 [ 78.160029] Internal error: Oops: 86000007 [#1] SMP [ 78.164886] Modules linked in: sunrpc vfat fat aes_ce_blk crypto_simd cryptd aes_ce_cipher crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce ses enclosure sg sbsa_gwdt ipmi_ssif spi_dw_mmio sch_fq_codel vhost_net tun vhost vhost_iotlb tap ip_tables ext4 mbcache jbd2 ahci hisi_sas_v3_hw libahci hisi_sas_main libsas hns3 scsi_transport_sas hclge libata megaraid_sas ipmi_si hnae3 ipmi_devintf ipmi_msghandler br_netfilter bridge stp llc nvme nvme_core xt_sctp sctp libcrc32c dm_mod nbd [ 78.207383] CPU: 11 PID: 23258 Comm: null-ptr Not tainted 5.8.0-rc6+ #48 [ 78.214056] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B210.01 03/12/2020 [ 78.222888] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--) [ 78.228435] pc : 0x0 [ 78.230618] lr : serial8250_start_tx+0x160/0x260 [ 78.235215] sp : ffff800062eefb80 [ 78.238517] x29: ffff800062eefb80 x28: 0000000000000fff [ 78.243807] x27: ffff800062eefd80 x26: ffff202fd83b3000 [ 78.249098] x25: ffff800062eefd80 x24: ffff202fd83b3000 [ 78.254388] x23: ffff002fc5e50be8 x22: 0000000000000002 [ 78.259679] x21: 0000000000000001 x20: 0000000000000000 [ 78.264969] x19: ffffa688827eecc8 x18: 0000000000000000 [ 78.270259] x17: 0000000000000000 x16: 0000000000000000 [ 78.275550] x15: ffffa68881bc67a8 x14: 00000000000002e6 [ 78.280841] x13: ffffa68881bc67a8 x12: 000000000000c539 [ 78.286131] x11: d37a6f4de9bd37a7 x10: ffffa68881cccff0 [ 78.291421] x9 : ffffa68881bc6000 x8 : ffffa688819daa88 [ 78.296711] x7 : ffffa688822a0f20 x6 : ffffa688819e0000 [ 78.302002] x5 : ffff800062eef9d0 x4 : ffffa68881e707a8 [ 78.307292] x3 : 0000000000000000 x2 : 0000000000000002 [ 78.312582] x1 : 0000000000000001 x0 : ffffa688827eecc8 [ 78.317873] Call trace: [ 78.320312] 0x0 [ 78.322147] __uart_start.isra.9+0x64/0x78 [ 78.326229] uart_start+0xb8/0x1c8 [ 78.329620] uart_flush_chars+0x24/0x30 [ 78.333442] n_tty_receive_buf_common+0x7b0/0xc30 [ 78.338128] n_tty_receive_buf+0x44/0x2c8 [ 78.342122] tty_ioctl+0x348/0x11f8 [ 78.345599] ksys_ioctl+0xd8/0xf8 [ 78.348903] __arm64_sys_ioctl+0x2c/0xc8 [ 78.352812] el0_svc_common.constprop.2+0x88/0x1b0 [ 78.357583] do_el0_svc+0x44/0xd0 [ 78.360887] el0_sync_handler+0x14c/0x1d0 [ 78.364880] el0_sync+0x140/0x180 [ 78.368185] Code: bad PC value SERIAL_PORT_DFNS is not defined on each arch, if it's not defined, serial8250_set_defaults() won't be called in serial8250_isa_init_ports(), so the p->serial_in pointer won't be initialized, and it leads a null-ptr-deref. Fix this problem by calling serial8250_set_defaults() after init uart port. Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200721143852.4058352-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-07-21 21:23:18 +02:00
..
hvc	tty: hvc_console, fix crashes on parallel open/close	2020-05-27 10:55:36 +02:00
ipwireless
serdev	serdev: Fix detection of UART devices on Apple machines.	2020-03-06 14:10:44 +01:00
serial	serial: 8250: fix null-ptr-deref in serial8250_start_tx()	2020-07-21 21:23:18 +02:00
vt	vt: Reject zero-sized screen buffer size.	2020-07-21 18:07:15 +02:00
amiserial.c
cyclades.c	remove ioremap_nocache and devm_ioremap_nocache	2020-01-06 09:45:59 +01:00
ehv_bytechan.c	tty: evh_bytechan: Fix out of bounds accesses	2020-03-17 23:40:31 +11:00
goldfish.c
isicom.c
Kconfig	treewide: replace '---help---' in Kconfig files with 'help'	2020-06-14 01:57:21 +09:00
Makefile
mips_ejtag_fdc.c	tty: mips_ejtag_fdc: Mark expected switch fall-through	2020-03-07 09:52:02 +01:00
moxa.c	remove ioremap_nocache and devm_ioremap_nocache	2020-01-06 09:45:59 +01:00
moxa.h
mxser.c	tty: mxser: make mxser_change_speed() return void	2020-05-15 14:47:05 +02:00
mxser.h
n_gsm.c	tty: n_gsm: Fix bogus i++ in gsm_data_kick	2020-05-19 16:19:54 +02:00
n_hdlc.c	n_hdlc_tty_read(): remove pointless access_ok()	2020-05-29 11:03:03 -04:00
n_null.c
n_r3964.c
n_tracerouter.c
n_tracesink.c
n_tracesink.h	tty: n_tracesink: Use the correct style for SPDX License Identifier	2020-03-18 13:01:31 +01:00
n_tty.c	n_tty: Distribute switch variables for initialization	2020-02-23 20:14:50 +01:00
nozomi.c	tty: nozomi: Use scnprintf() for avoiding potential buffer overflow	2020-03-18 12:59:29 +01:00
pty.c
rocket.c	Merge 5.7-rc3 into tty-next	2020-04-27 09:33:21 +02:00
rocket.h
rocket_int.h
synclink.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next	2020-01-28 16:02:33 -08:00
synclink_gt.c	TTY/Serial driver updates for 5.6-rc1	2020-01-29 10:13:27 -08:00
synclinkmp.c	TTY/Serial driver updates for 5.6-rc1	2020-01-29 10:13:27 -08:00
sysrq.c	kernel: rename show_stack_loglvl() => show_stack()	2020-06-09 09:39:13 -07:00
tty_audit.c
tty_baudrate.c	tty: baudrate: SPARC supports few more baud rates	2020-01-22 10:23:26 +01:00
tty_buffer.c
tty_io.c	tty: fix compat TIOCGSERIAL checking wrong function ptr	2020-03-18 13:15:13 +01:00
tty_ioctl.c
tty_jobctrl.c
tty_ldisc.c
tty_ldsem.c
tty_mutex.c
tty_port.c	serdev: ttyport: restore client ops on deregistration	2020-02-10 12:26:44 -08:00
ttynull.c
vcc.c	sparc64: vcc: Fix error return code in vcc_probe()	2020-04-28 14:38:54 +02:00