commit dada6a43b0402eba438a17ac86fdc64ac56a4607 upstream. This patch is trying to fix KE issue due to "BUG: KASAN: global-out-of-bounds in param_set_kgdboc_var+0x194/0x198" reported by Syzkaller scan." [26364:syz-executor0][name:report8t]BUG: KASAN: global-out-of-bounds in param_set_kgdboc_var+0x194/0x198 [26364:syz-executor0][name:report&]Read of size 1 at addr ffffff900e44f95f by task syz-executor0/26364 [26364:syz-executor0][name:report&] [26364:syz-executor0]CPU: 7 PID: 26364 Comm: syz-executor0 Tainted: G W 0 [26364:syz-executor0]Call trace: [26364:syz-executor0][<ffffff9008095cf8>] dump_bacIctrace+Ox0/0x470 [26364:syz-executor0][<ffffff9008096de0>] show_stack+0x20/0x30 [26364:syz-executor0][<ffffff90089cc9c8>] dump_stack+Oxd8/0x128 [26364:syz-executor0][<ffffff90084edb38>] print_address_description +0x80/0x4a8 [26364:syz-executor0][<ffffff90084ee270>] kasan_report+Ox178/0x390 [26364:syz-executor0][<ffffff90084ee4a0>] _asan_report_loadi_noabort+Ox18/0x20 [26364:syz-executor0][<ffffff9008b092ac>] param_set_kgdboc_var+Ox194/0x198 [26364:syz-executor0][<ffffff900813af64>] param_attr_store+Ox14c/0x270 [26364:syz-executor0][<ffffff90081394c8>] module_attr_store+0x60/0x90 [26364:syz-executor0][<ffffff90086690c0>] sysfs_kl_write+Ox100/0x158 [26364:syz-executor0][<ffffff9008666d84>] kernfs_fop_write+0x27c/0x3a8 [26364:syz-executor0][<ffffff9008508264>] do_loop_readv_writev+0x114/0x1b0 [26364:syz-executor0][<ffffff9008509ac8>] do_readv_writev+0x4f8/0x5e0 [26364:syz-executor0][<ffffff9008509ce4>] vfs_writev+0x7c/Oxb8 [26364:syz-executor0][<ffffff900850ba64>] SyS_writev+Oxcc/0x208 [26364:syz-executor0][<ffffff90080883f0>] elO_svc_naked +0x24/0x28 [26364:syz-executor0][name:report&] [26364:syz-executor0][name:report&]The buggy address belongs to the variable: [26364:syz-executor0][name:report&] kgdb_tty_line+Ox3f/0x40 [26364:syz-executor0][name:report&] [26364:syz-executor0][name:report&]Memory state around the buggy address: [26364:syz-executor0] ffffff900e44f800: 00 00 00 00 00 04 fa fa fa fa fa fa 00 fa fa fa [26364:syz-executor0] ffffff900e44f880: fa fa fa fa 00 fa fa fa fa fa fa fa 00 fa fa fa [26364:syz-executor0]> ffffff900e44f900: fa fa fa fa 04 fa fa fa fa fa fa fa 00 00 00 00 [26364:syz-executor0][name:report&] ^ [26364:syz-executor0] ffffff900e44f980: 00 fa fa fa fa fa fa fa 04 fa fa fa fa fa fa fa [26364:syz-executor0] ffffff900e44fa00: 04 fa fa fa fa fa fa fa 00 fa fa fa fa fa fa fa [26364:syz-executor0][name:report&] [26364:syz-executor0][name:panic&]Disabling lock debugging due to kernel taint [26364:syz-executor0]------------[cut here]------------ After checking the source code, we've found there might be an out-of-bounds access to "config[len - 1]" array when the variable "len" is zero. Signed-off-by: Macpaul Lin <macpaul@gmail.com> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 991a25194097006ec1e0d2e0814ff920e59e3465 upstream. On architectures with CBAUDEX == 0 (Alpha and PowerPC), the code in tty_baudrate.c does not do any limit checking on the tty_baudrate[] array, and in fact a buffer overrun is possible on both architectures. Add a limit check to prevent that situation. This will be followed by a much bigger cleanup/simplification patch. Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Requested-by: Cc: Johan Hovold <johan@kernel.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Eugene Syromiatnikov <esyr@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.16: adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 1bd54d851f50dea6af30c3e6ff4f3e9aab5558f9 upstream. kgdboc_option_setup does not check input argument before passing it to strlen. The argument would be a NULL pointer if "ekgdboc", without its value, is set in command line and thus cause the following panic. PANIC: early exception 0xe3 IP 10:ffffffff8fbbb620 error 0 cr2 0x0 [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.18-rc8+ #1 [ 0.000000] RIP: 0010:strlen+0x0/0x20 ... [ 0.000000] Call Trace [ 0.000000] ? kgdboc_option_setup+0x9/0xa0 [ 0.000000] ? kgdboc_early_init+0x6/0x1b [ 0.000000] ? do_early_param+0x4d/0x82 [ 0.000000] ? parse_args+0x212/0x330 [ 0.000000] ? rdinit_setup+0x26/0x26 [ 0.000000] ? parse_early_options+0x20/0x23 [ 0.000000] ? rdinit_setup+0x26/0x26 [ 0.000000] ? parse_early_param+0x2d/0x39 [ 0.000000] ? setup_arch+0x2f7/0xbf4 [ 0.000000] ? start_kernel+0x5e/0x4c2 [ 0.000000] ? load_ucode_bsp+0x113/0x12f [ 0.000000] ? secondary_startup_64+0xa5/0xb0 This patch adds a check to prevent the panic. Cc: jason.wessel@windriver.com Cc: gregkh@linuxfoundation.org Cc: jslaby@suse.com Signed-off-by: He Zhe <zhe.he@windriver.com> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit e97267cb4d1ee01ca0929638ec0fcbb0904f903d upstream. vsa.console is indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. This issue was detected with the help of Smatch: drivers/tty/vt/vt_ioctl.c:711 vt_ioctl() warn: potential spectre issue 'vc_cons' [r] Fix this by sanitizing vsa.console before using it to index vc_cons Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit be28c1e3ca29887e207f0cbcd294cefe5074bab6 upstream.
kgdb expects poll function to return immediately and
returning NO_POLL_CHAR when no character is available.
Fixes: f5316b4aea024 ("kgdb,8250,pl011: Return immediately from console poll")
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 1cee38f0363a88db374e50b232ca17b9a4c12fa0 upstream.
When the termios CIBAUD bits are left unset (i.e. B0), we use the same
output and input speed and should leave CIBAUD unchanged.
When the user requests a rate using BOTHER and c_ospeed which the driver
cannot set exactly, the driver can report back the actual baud rate
using tty_termios_encode_baud_rate(). If this rate is close enough to a
standard rate however, we could end up setting CIBAUD to a Bfoo value
despite the user having left it unset.
This in turn could lead to an unexpected input rate being set on
subsequent termios updates.
Fix this by using a zero tolerance value also for the input rate when
CIBAUD is clear so that the matching logic works as expected.
Fixes: 78137e3b34e1 ("[PATCH] tty: improve encode_baud_rate logic")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit fada18c48d774b9e837928ecdce6a5d5fdd11ee7 upstream.
Make sure to clear the CIBAUD bits before OR-ing the new mask when
encoding the termios input baud rate.
This could otherwise lead to an incorrect input rate being reported back
and incidentally set on subsequent termios updates.
Fixes: edc6afc54968 ("[PATCH] tty: switch to ktermios and new framework")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit a1d51aa2214cea3f91611893610a2f769cada0e7 upstream. Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit a5ba1d95e46ecaea638ddd7cd144107c783acb5d upstream.
We have reports of the following crash:
PID: 7 TASK: ffff88085c6d61c0 CPU: 1 COMMAND: "kworker/u25:0"
#0 [ffff88085c6db710] machine_kexec at ffffffff81046239
#1 [ffff88085c6db760] crash_kexec at ffffffff810fc248
#2 [ffff88085c6db830] oops_end at ffffffff81008ae7
#3 [ffff88085c6db860] no_context at ffffffff81050b8f
#4 [ffff88085c6db8b0] __bad_area_nosemaphore at ffffffff81050d75
#5 [ffff88085c6db900] bad_area_nosemaphore at ffffffff81050e83
#6 [ffff88085c6db910] __do_page_fault at ffffffff8105132e
#7 [ffff88085c6db9b0] do_page_fault at ffffffff8105152c
#8 [ffff88085c6db9c0] page_fault at ffffffff81a3f122
[exception RIP: uart_put_char+149]
RIP: ffffffff814b67b5 RSP: ffff88085c6dba78 RFLAGS: 00010006
RAX: 0000000000000292 RBX: ffffffff827c5120 RCX: 0000000000000081
RDX: 0000000000000000 RSI: 000000000000005f RDI: ffffffff827c5120
RBP: ffff88085c6dba98 R8: 000000000000012c R9: ffffffff822ea320
R10: ffff88085fe4db04 R11: 0000000000000001 R12: ffff881059f9c000
R13: 0000000000000001 R14: 000000000000005f R15: 0000000000000fba
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#9 [ffff88085c6dbaa0] tty_put_char at ffffffff81497544
#10 [ffff88085c6dbac0] do_output_char at ffffffff8149c91c
#11 [ffff88085c6dbae0] __process_echoes at ffffffff8149cb8b
#12 [ffff88085c6dbb30] commit_echoes at ffffffff8149cdc2
#13 [ffff88085c6dbb60] n_tty_receive_buf_fast at ffffffff8149e49b
#14 [ffff88085c6dbbc0] __receive_buf at ffffffff8149ef5a
#15 [ffff88085c6dbc20] n_tty_receive_buf_common at ffffffff8149f016
#16 [ffff88085c6dbca0] n_tty_receive_buf2 at ffffffff8149f194
#17 [ffff88085c6dbcb0] flush_to_ldisc at ffffffff814a238a
#18 [ffff88085c6dbd50] process_one_work at ffffffff81090be2
#19 [ffff88085c6dbe20] worker_thread at ffffffff81091b4d
#20 [ffff88085c6dbeb0] kthread at ffffffff81096384
#21 [ffff88085c6dbf50] ret_from_fork at ffffffff81a3d69f
after slogging through some dissasembly:
ffffffff814b6720 <uart_put_char>:
ffffffff814b6720: 55 push %rbp
ffffffff814b6721: 48 89 e5 mov %rsp,%rbp
ffffffff814b6724: 48 83 ec 20 sub $0x20,%rsp
ffffffff814b6728: 48 89 1c 24 mov %rbx,(%rsp)
ffffffff814b672c: 4c 89 64 24 08 mov %r12,0x8(%rsp)
ffffffff814b6731: 4c 89 6c 24 10 mov %r13,0x10(%rsp)
ffffffff814b6736: 4c 89 74 24 18 mov %r14,0x18(%rsp)
ffffffff814b673b: e8 b0 8e 58 00 callq ffffffff81a3f5f0 <mcount>
ffffffff814b6740: 4c 8b a7 88 02 00 00 mov 0x288(%rdi),%r12
ffffffff814b6747: 45 31 ed xor %r13d,%r13d
ffffffff814b674a: 41 89 f6 mov %esi,%r14d
ffffffff814b674d: 49 83 bc 24 70 01 00 cmpq $0x0,0x170(%r12)
ffffffff814b6754: 00 00
ffffffff814b6756: 49 8b 9c 24 80 01 00 mov 0x180(%r12),%rbx
ffffffff814b675d: 00
ffffffff814b675e: 74 2f je ffffffff814b678f <uart_put_char+0x6f>
ffffffff814b6760: 48 89 df mov %rbx,%rdi
ffffffff814b6763: e8 a8 67 58 00 callq ffffffff81a3cf10 <_raw_spin_lock_irqsave>
ffffffff814b6768: 41 8b 8c 24 78 01 00 mov 0x178(%r12),%ecx
ffffffff814b676f: 00
ffffffff814b6770: 89 ca mov %ecx,%edx
ffffffff814b6772: f7 d2 not %edx
ffffffff814b6774: 41 03 94 24 7c 01 00 add 0x17c(%r12),%edx
ffffffff814b677b: 00
ffffffff814b677c: 81 e2 ff 0f 00 00 and $0xfff,%edx
ffffffff814b6782: 75 23 jne ffffffff814b67a7 <uart_put_char+0x87>
ffffffff814b6784: 48 89 c6 mov %rax,%rsi
ffffffff814b6787: 48 89 df mov %rbx,%rdi
ffffffff814b678a: e8 e1 64 58 00 callq ffffffff81a3cc70 <_raw_spin_unlock_irqrestore>
ffffffff814b678f: 44 89 e8 mov %r13d,%eax
ffffffff814b6792: 48 8b 1c 24 mov (%rsp),%rbx
ffffffff814b6796: 4c 8b 64 24 08 mov 0x8(%rsp),%r12
ffffffff814b679b: 4c 8b 6c 24 10 mov 0x10(%rsp),%r13
ffffffff814b67a0: 4c 8b 74 24 18 mov 0x18(%rsp),%r14
ffffffff814b67a5: c9 leaveq
ffffffff814b67a6: c3 retq
ffffffff814b67a7: 49 8b 94 24 70 01 00 mov 0x170(%r12),%rdx
ffffffff814b67ae: 00
ffffffff814b67af: 48 63 c9 movslq %ecx,%rcx
ffffffff814b67b2: 41 b5 01 mov $0x1,%r13b
ffffffff814b67b5: 44 88 34 0a mov %r14b,(%rdx,%rcx,1)
ffffffff814b67b9: 41 8b 94 24 78 01 00 mov 0x178(%r12),%edx
ffffffff814b67c0: 00
ffffffff814b67c1: 83 c2 01 add $0x1,%edx
ffffffff814b67c4: 81 e2 ff 0f 00 00 and $0xfff,%edx
ffffffff814b67ca: 41 89 94 24 78 01 00 mov %edx,0x178(%r12)
ffffffff814b67d1: 00
ffffffff814b67d2: eb b0 jmp ffffffff814b6784 <uart_put_char+0x64>
ffffffff814b67d4: 66 66 66 2e 0f 1f 84 data32 data32 nopw %cs:0x0(%rax,%rax,1)
ffffffff814b67db: 00 00 00 00 00
for our build, this is crashing at:
circ->buf[circ->head] = c;
Looking in uart_port_startup(), it seems that circ->buf (state->xmit.buf)
protected by the "per-port mutex", which based on uart_port_check() is
state->port.mutex. Indeed, the lock acquired in uart_put_char() is
uport->lock, i.e. not the same lock.
Anyway, since the lock is not acquired, if uart_shutdown() is called, the
last chunk of that function may release state->xmit.buf before its assigned
to null, and cause the race above.
To fix it, let's lock uport->lock when allocating/deallocating
state->xmit.buf in addition to the per-port mutex.
v2: switch to locking uport->lock on allocation/deallocation instead of
locking the per-port mutex in uart_put_char. Note that since
uport->lock is a spin lock, we have to switch the allocation to
GFP_ATOMIC.
v3: move the allocation outside the lock, so we can switch back to
GFP_KERNEL
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: Use uport->lock directly rather than through
uart_port_{,un}lock()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 95a0e656580fab3128c7bee5f660c50784f53651 upstream.
If port.line is out of range, we still need to release some resources, or
we will leak them.
Fixes: afc7851fab83 ("serial: pxa: Fix out-of-bounds access through serial port index")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>