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PL011: no DMA platform data #396

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jansendup opened this issue Oct 10, 2013 · 8 comments
Closed

PL011: no DMA platform data #396

jansendup opened this issue Oct 10, 2013 · 8 comments

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@jansendup
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in drivers/tty/serial/amba-pl011.c uap->port.dev->platform_data is NULL on the bcm2835 arch causing DMA probe to fail. thus no DMA on the uart module.

@popcornmix
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Is there an upstream commit I can pull in?

@jansendup
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Not quite sure where to look. Maybe you can check.
In arch/arm/mach-bcm2708/bcm2708.c line 242: "AMBA_DEVICE(uart0, "dev:f1", UART0, NULL);"
The last parameter of AMBA_DEVICE should be a pointer to a "struct amba_pl011_data" that is defined in include/linux/amba/serial.h line 201.

@popcornmix
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It is not possible to dma from/to the uart, so I think a DMA probe failure is correct.

@P33M
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P33M commented Oct 10, 2013

In the BCM2835 peripherals datasheet, UART1 is explicitly defined as having no DMA support. UART0 has a DREQ line entry for tx/rx in the DMA controller section - DREQ 12/14 respectively.

Are there free DMA channels for use by the UART?

@jansendup
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I quickly tried setting filter_fn in struct dma_chan *dma_request_channel(dma_cap_mask_t mask,dma_filter_fn filter_fn,void *filter_param); to NULL. If I understand it correctly, dma_request_channel should just then return any available channel. It returned NULL so it might be that there aren't any available channels. dma_request_slave_channel(dev, "tx") also returned NULL.

@jansendup
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It seems that there is no dmaengine driver for the BCM2835 so thats probably why the last parameter in arch/arm/mach-bcm2708/bcm2708.c line 242: "AMBA_DEVICE(uart0, "dev:f1", UART0, NULL);" is NULL.

@P33M
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P33M commented Oct 11, 2013

It appears you are correct; there are no dma engine drivers for either the bcm2708 port (this repo) or the upstream bcm2835 port. It looks like several people have had a go but not upstreamed it.

It would be necessary to get a platform DMA driver implemented before adding support to the peripheral drivers (i2c/spi/uart).

@popcornmix
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@jansendup
I assume there is nothing to change here - okay to close?

popcornmix pushed a commit that referenced this issue Mar 31, 2014
policy->rwsem is used to lock access to all parts of code modifying
struct cpufreq_policy, but it's not used on a new policy created by
__cpufreq_add_dev().

Because of that, if cpufreq_update_policy() is called in a tight loop
on one CPU in parallel with offline/online of another CPU, then the
following crash can be triggered:

Unable to handle kernel NULL pointer dereference at virtual address 00000020
pgd = c0003000
[00000020] *pgd=80000000004003, *pmd=00000000
Internal error: Oops: 206 [#1] PREEMPT SMP ARM

PC is at __cpufreq_governor+0x10/0x1ac
LR is at cpufreq_update_policy+0x114/0x150

---[ end trace f23a8defea6cd706 ]---
Kernel panic - not syncing: Fatal exception
CPU0: stopping
CPU: 0 PID: 7136 Comm: mpdecision Tainted: G      D W    3.10.0-gd727407-00074-g979ede8 #396

[<c0afe180>] (notifier_call_chain+0x40/0x68) from [<c02a23ac>] (__blocking_notifier_call_chain+0x40/0x58)
[<c02a23ac>] (__blocking_notifier_call_chain+0x40/0x58) from [<c02a23d8>] (blocking_notifier_call_chain+0x14/0x1c)
[<c02a23d8>] (blocking_notifier_call_chain+0x14/0x1c) from [<c0803c68>] (cpufreq_set_policy+0xd4/0x2b8)
[<c0803c68>] (cpufreq_set_policy+0xd4/0x2b8) from [<c0803e7c>] (cpufreq_init_policy+0x30/0x98)
[<c0803e7c>] (cpufreq_init_policy+0x30/0x98) from [<c0805a18>] (__cpufreq_add_dev.isra.17+0x4dc/0x7a4)
[<c0805a18>] (__cpufreq_add_dev.isra.17+0x4dc/0x7a4) from [<c0805d38>] (cpufreq_cpu_callback+0x58/0x84)
[<c0805d38>] (cpufreq_cpu_callback+0x58/0x84) from [<c0afe180>] (notifier_call_chain+0x40/0x68)
[<c0afe180>] (notifier_call_chain+0x40/0x68) from [<c02812dc>] (__cpu_notify+0x28/0x44)
[<c02812dc>] (__cpu_notify+0x28/0x44) from [<c0aeed90>] (_cpu_up+0xf4/0x1dc)
[<c0aeed90>] (_cpu_up+0xf4/0x1dc) from [<c0aeeed4>] (cpu_up+0x5c/0x78)
[<c0aeeed4>] (cpu_up+0x5c/0x78) from [<c0aec808>] (store_online+0x44/0x74)
[<c0aec808>] (store_online+0x44/0x74) from [<c03a40f4>] (sysfs_write_file+0x108/0x14c)
[<c03a40f4>] (sysfs_write_file+0x108/0x14c) from [<c03517d4>] (vfs_write+0xd0/0x180)
[<c03517d4>] (vfs_write+0xd0/0x180) from [<c0351ca8>] (SyS_write+0x38/0x68)
[<c0351ca8>] (SyS_write+0x38/0x68) from [<c0205de0>] (ret_fast_syscall+0x0/0x30)

Fix that by taking locks at appropriate places in __cpufreq_add_dev()
as well.

Reported-by: Saravana Kannan <skannan@codeaurora.org>
Suggested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
skullandbones pushed a commit to skullandbones/linux that referenced this issue Jul 29, 2019
[ Upstream commit 28261da ]

Because of both sides doing L2CAP disconnection at the same time, it
was possible to receive L2CAP Disconnection Response with CID that was
already freed. That caused problems if CID was already reused and L2CAP
Connection Request with same CID was sent out. Before this patch kernel
deleted channel context regardless of the state of the channel.

Example where leftover Disconnection Response (frame raspberrypi#402) causes local
device to delete L2CAP channel which was not yet connected. This in
turn confuses remote device's stack because same CID is re-used without
properly disconnecting.

Btmon capture before patch:
** snip **
> ACL Data RX: Handle 43 flags 0x02 dlen 8                raspberrypi#394 [hci1] 10.748949
      Channel: 65 len 4 [PSM 3 mode 0] {chan 2}
      RFCOMM: Disconnect (DISC) (0x43)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x53 poll/final 1
         Length: 0
         FCS: 0xfd
< ACL Data TX: Handle 43 flags 0x00 dlen 8                raspberrypi#395 [hci1] 10.749062
      Channel: 65 len 4 [PSM 3 mode 0] {chan 2}
      RFCOMM: Unnumbered Ack (UA) (0x63)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x73 poll/final 1
         Length: 0
         FCS: 0xd7
< ACL Data TX: Handle 43 flags 0x00 dlen 12               raspberrypi#396 [hci1] 10.749073
      L2CAP: Disconnection Request (0x06) ident 17 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Packets (0x13) plen 5    raspberrypi#397 [hci1] 10.752391
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5    raspberrypi#398 [hci1] 10.753394
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12               raspberrypi#399 [hci1] 10.756499
      L2CAP: Disconnection Request (0x06) ident 26 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12               raspberrypi#400 [hci1] 10.756548
      L2CAP: Disconnection Response (0x07) ident 26 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12               raspberrypi#401 [hci1] 10.757459
      L2CAP: Connection Request (0x02) ident 18 len 4
        PSM: 1 (0x0001)
        Source CID: 65
> ACL Data RX: Handle 43 flags 0x02 dlen 12               raspberrypi#402 [hci1] 10.759148
      L2CAP: Disconnection Response (0x07) ident 17 len 4
        Destination CID: 65
        Source CID: 65
= bluetoothd: 00:1E:AB:4C:56:54: error updating services: Input/o..   10.759447
> HCI Event: Number of Completed Packets (0x13) plen 5    raspberrypi#403 [hci1] 10.759386
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12               raspberrypi#404 [hci1] 10.760397
      L2CAP: Connection Request (0x02) ident 27 len 4
        PSM: 3 (0x0003)
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 16               raspberrypi#405 [hci1] 10.760441
      L2CAP: Connection Response (0x03) ident 27 len 8
        Destination CID: 65
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 43 flags 0x00 dlen 27               raspberrypi#406 [hci1] 10.760449
      L2CAP: Configure Request (0x04) ident 19 len 19
        Destination CID: 65
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1013
        Option: Retransmission and Flow Control (0x04) [mandatory]
          Mode: Basic (0x00)
          TX window size: 0
          Max transmit: 0
          Retransmission timeout: 0
          Monitor timeout: 0
          Maximum PDU size: 0
> HCI Event: Number of Completed Packets (0x13) plen 5    raspberrypi#407 [hci1] 10.761399
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 16               raspberrypi#408 [hci1] 10.762942
      L2CAP: Connection Response (0x03) ident 18 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
*snip*

Similar case after the patch:
*snip*
> ACL Data RX: Handle 43 flags 0x02 dlen 8            #22702 [hci0] 1664.411056
      Channel: 65 len 4 [PSM 3 mode 0] {chan 3}
      RFCOMM: Disconnect (DISC) (0x43)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x53 poll/final 1
         Length: 0
         FCS: 0xfd
< ACL Data TX: Handle 43 flags 0x00 dlen 8            #22703 [hci0] 1664.411136
      Channel: 65 len 4 [PSM 3 mode 0] {chan 3}
      RFCOMM: Unnumbered Ack (UA) (0x63)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x73 poll/final 1
         Length: 0
         FCS: 0xd7
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22704 [hci0] 1664.411143
      L2CAP: Disconnection Request (0x06) ident 11 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22705 [hci0] 1664.414009
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22706 [hci0] 1664.415007
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22707 [hci0] 1664.418674
      L2CAP: Disconnection Request (0x06) ident 17 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22708 [hci0] 1664.418762
      L2CAP: Disconnection Response (0x07) ident 17 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22709 [hci0] 1664.421073
      L2CAP: Connection Request (0x02) ident 12 len 4
        PSM: 1 (0x0001)
        Source CID: 65
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22710 [hci0] 1664.421371
      L2CAP: Disconnection Response (0x07) ident 11 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22711 [hci0] 1664.424082
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22712 [hci0] 1664.425040
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22713 [hci0] 1664.426103
      L2CAP: Connection Request (0x02) ident 18 len 4
        PSM: 3 (0x0003)
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 16           #22714 [hci0] 1664.426186
      L2CAP: Connection Response (0x03) ident 18 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 43 flags 0x00 dlen 27           #22715 [hci0] 1664.426196
      L2CAP: Configure Request (0x04) ident 13 len 19
        Destination CID: 65
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1013
        Option: Retransmission and Flow Control (0x04) [mandatory]
          Mode: Basic (0x00)
          TX window size: 0
          Max transmit: 0
          Retransmission timeout: 0
          Monitor timeout: 0
          Maximum PDU size: 0
> ACL Data RX: Handle 43 flags 0x02 dlen 16           #22716 [hci0] 1664.428804
      L2CAP: Connection Response (0x03) ident 12 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
*snip*

Fix is to check that channel is in state BT_DISCONN before deleting the
channel.

This bug was found while fuzzing Bluez's OBEX implementation using
Synopsys Defensics.

Reported-by: Matti Kamunen <matti.kamunen@synopsys.com>
Reported-by: Ari Timonen <ari.timonen@synopsys.com>
Signed-off-by: Matias Karhumaa <matias.karhumaa@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
popcornmix pushed a commit that referenced this issue Jul 31, 2019
[ Upstream commit 28261da ]

Because of both sides doing L2CAP disconnection at the same time, it
was possible to receive L2CAP Disconnection Response with CID that was
already freed. That caused problems if CID was already reused and L2CAP
Connection Request with same CID was sent out. Before this patch kernel
deleted channel context regardless of the state of the channel.

Example where leftover Disconnection Response (frame #402) causes local
device to delete L2CAP channel which was not yet connected. This in
turn confuses remote device's stack because same CID is re-used without
properly disconnecting.

Btmon capture before patch:
** snip **
> ACL Data RX: Handle 43 flags 0x02 dlen 8                #394 [hci1] 10.748949
      Channel: 65 len 4 [PSM 3 mode 0] {chan 2}
      RFCOMM: Disconnect (DISC) (0x43)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x53 poll/final 1
         Length: 0
         FCS: 0xfd
< ACL Data TX: Handle 43 flags 0x00 dlen 8                #395 [hci1] 10.749062
      Channel: 65 len 4 [PSM 3 mode 0] {chan 2}
      RFCOMM: Unnumbered Ack (UA) (0x63)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x73 poll/final 1
         Length: 0
         FCS: 0xd7
< ACL Data TX: Handle 43 flags 0x00 dlen 12               #396 [hci1] 10.749073
      L2CAP: Disconnection Request (0x06) ident 17 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Packets (0x13) plen 5    #397 [hci1] 10.752391
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5    #398 [hci1] 10.753394
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12               #399 [hci1] 10.756499
      L2CAP: Disconnection Request (0x06) ident 26 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12               #400 [hci1] 10.756548
      L2CAP: Disconnection Response (0x07) ident 26 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12               #401 [hci1] 10.757459
      L2CAP: Connection Request (0x02) ident 18 len 4
        PSM: 1 (0x0001)
        Source CID: 65
> ACL Data RX: Handle 43 flags 0x02 dlen 12               #402 [hci1] 10.759148
      L2CAP: Disconnection Response (0x07) ident 17 len 4
        Destination CID: 65
        Source CID: 65
= bluetoothd: 00:1E:AB:4C:56:54: error updating services: Input/o..   10.759447
> HCI Event: Number of Completed Packets (0x13) plen 5    #403 [hci1] 10.759386
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12               #404 [hci1] 10.760397
      L2CAP: Connection Request (0x02) ident 27 len 4
        PSM: 3 (0x0003)
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 16               #405 [hci1] 10.760441
      L2CAP: Connection Response (0x03) ident 27 len 8
        Destination CID: 65
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 43 flags 0x00 dlen 27               #406 [hci1] 10.760449
      L2CAP: Configure Request (0x04) ident 19 len 19
        Destination CID: 65
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1013
        Option: Retransmission and Flow Control (0x04) [mandatory]
          Mode: Basic (0x00)
          TX window size: 0
          Max transmit: 0
          Retransmission timeout: 0
          Monitor timeout: 0
          Maximum PDU size: 0
> HCI Event: Number of Completed Packets (0x13) plen 5    #407 [hci1] 10.761399
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 16               #408 [hci1] 10.762942
      L2CAP: Connection Response (0x03) ident 18 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
*snip*

Similar case after the patch:
*snip*
> ACL Data RX: Handle 43 flags 0x02 dlen 8            #22702 [hci0] 1664.411056
      Channel: 65 len 4 [PSM 3 mode 0] {chan 3}
      RFCOMM: Disconnect (DISC) (0x43)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x53 poll/final 1
         Length: 0
         FCS: 0xfd
< ACL Data TX: Handle 43 flags 0x00 dlen 8            #22703 [hci0] 1664.411136
      Channel: 65 len 4 [PSM 3 mode 0] {chan 3}
      RFCOMM: Unnumbered Ack (UA) (0x63)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x73 poll/final 1
         Length: 0
         FCS: 0xd7
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22704 [hci0] 1664.411143
      L2CAP: Disconnection Request (0x06) ident 11 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22705 [hci0] 1664.414009
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22706 [hci0] 1664.415007
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22707 [hci0] 1664.418674
      L2CAP: Disconnection Request (0x06) ident 17 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22708 [hci0] 1664.418762
      L2CAP: Disconnection Response (0x07) ident 17 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22709 [hci0] 1664.421073
      L2CAP: Connection Request (0x02) ident 12 len 4
        PSM: 1 (0x0001)
        Source CID: 65
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22710 [hci0] 1664.421371
      L2CAP: Disconnection Response (0x07) ident 11 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22711 [hci0] 1664.424082
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22712 [hci0] 1664.425040
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22713 [hci0] 1664.426103
      L2CAP: Connection Request (0x02) ident 18 len 4
        PSM: 3 (0x0003)
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 16           #22714 [hci0] 1664.426186
      L2CAP: Connection Response (0x03) ident 18 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 43 flags 0x00 dlen 27           #22715 [hci0] 1664.426196
      L2CAP: Configure Request (0x04) ident 13 len 19
        Destination CID: 65
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1013
        Option: Retransmission and Flow Control (0x04) [mandatory]
          Mode: Basic (0x00)
          TX window size: 0
          Max transmit: 0
          Retransmission timeout: 0
          Monitor timeout: 0
          Maximum PDU size: 0
> ACL Data RX: Handle 43 flags 0x02 dlen 16           #22716 [hci0] 1664.428804
      L2CAP: Connection Response (0x03) ident 12 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
*snip*

Fix is to check that channel is in state BT_DISCONN before deleting the
channel.

This bug was found while fuzzing Bluez's OBEX implementation using
Synopsys Defensics.

Reported-by: Matti Kamunen <matti.kamunen@synopsys.com>
Reported-by: Ari Timonen <ari.timonen@synopsys.com>
Signed-off-by: Matias Karhumaa <matias.karhumaa@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
popcornmix pushed a commit that referenced this issue Jul 31, 2019
[ Upstream commit 28261da ]

Because of both sides doing L2CAP disconnection at the same time, it
was possible to receive L2CAP Disconnection Response with CID that was
already freed. That caused problems if CID was already reused and L2CAP
Connection Request with same CID was sent out. Before this patch kernel
deleted channel context regardless of the state of the channel.

Example where leftover Disconnection Response (frame #402) causes local
device to delete L2CAP channel which was not yet connected. This in
turn confuses remote device's stack because same CID is re-used without
properly disconnecting.

Btmon capture before patch:
** snip **
> ACL Data RX: Handle 43 flags 0x02 dlen 8                #394 [hci1] 10.748949
      Channel: 65 len 4 [PSM 3 mode 0] {chan 2}
      RFCOMM: Disconnect (DISC) (0x43)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x53 poll/final 1
         Length: 0
         FCS: 0xfd
< ACL Data TX: Handle 43 flags 0x00 dlen 8                #395 [hci1] 10.749062
      Channel: 65 len 4 [PSM 3 mode 0] {chan 2}
      RFCOMM: Unnumbered Ack (UA) (0x63)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x73 poll/final 1
         Length: 0
         FCS: 0xd7
< ACL Data TX: Handle 43 flags 0x00 dlen 12               #396 [hci1] 10.749073
      L2CAP: Disconnection Request (0x06) ident 17 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Packets (0x13) plen 5    #397 [hci1] 10.752391
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5    #398 [hci1] 10.753394
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12               #399 [hci1] 10.756499
      L2CAP: Disconnection Request (0x06) ident 26 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12               #400 [hci1] 10.756548
      L2CAP: Disconnection Response (0x07) ident 26 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12               #401 [hci1] 10.757459
      L2CAP: Connection Request (0x02) ident 18 len 4
        PSM: 1 (0x0001)
        Source CID: 65
> ACL Data RX: Handle 43 flags 0x02 dlen 12               #402 [hci1] 10.759148
      L2CAP: Disconnection Response (0x07) ident 17 len 4
        Destination CID: 65
        Source CID: 65
= bluetoothd: 00:1E:AB:4C:56:54: error updating services: Input/o..   10.759447
> HCI Event: Number of Completed Packets (0x13) plen 5    #403 [hci1] 10.759386
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12               #404 [hci1] 10.760397
      L2CAP: Connection Request (0x02) ident 27 len 4
        PSM: 3 (0x0003)
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 16               #405 [hci1] 10.760441
      L2CAP: Connection Response (0x03) ident 27 len 8
        Destination CID: 65
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 43 flags 0x00 dlen 27               #406 [hci1] 10.760449
      L2CAP: Configure Request (0x04) ident 19 len 19
        Destination CID: 65
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1013
        Option: Retransmission and Flow Control (0x04) [mandatory]
          Mode: Basic (0x00)
          TX window size: 0
          Max transmit: 0
          Retransmission timeout: 0
          Monitor timeout: 0
          Maximum PDU size: 0
> HCI Event: Number of Completed Packets (0x13) plen 5    #407 [hci1] 10.761399
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 16               #408 [hci1] 10.762942
      L2CAP: Connection Response (0x03) ident 18 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
*snip*

Similar case after the patch:
*snip*
> ACL Data RX: Handle 43 flags 0x02 dlen 8            #22702 [hci0] 1664.411056
      Channel: 65 len 4 [PSM 3 mode 0] {chan 3}
      RFCOMM: Disconnect (DISC) (0x43)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x53 poll/final 1
         Length: 0
         FCS: 0xfd
< ACL Data TX: Handle 43 flags 0x00 dlen 8            #22703 [hci0] 1664.411136
      Channel: 65 len 4 [PSM 3 mode 0] {chan 3}
      RFCOMM: Unnumbered Ack (UA) (0x63)
         Address: 0x03 cr 1 dlci 0x00
         Control: 0x73 poll/final 1
         Length: 0
         FCS: 0xd7
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22704 [hci0] 1664.411143
      L2CAP: Disconnection Request (0x06) ident 11 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22705 [hci0] 1664.414009
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22706 [hci0] 1664.415007
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22707 [hci0] 1664.418674
      L2CAP: Disconnection Request (0x06) ident 17 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22708 [hci0] 1664.418762
      L2CAP: Disconnection Response (0x07) ident 17 len 4
        Destination CID: 65
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 12           #22709 [hci0] 1664.421073
      L2CAP: Connection Request (0x02) ident 12 len 4
        PSM: 1 (0x0001)
        Source CID: 65
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22710 [hci0] 1664.421371
      L2CAP: Disconnection Response (0x07) ident 11 len 4
        Destination CID: 65
        Source CID: 65
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22711 [hci0] 1664.424082
        Num handles: 1
        Handle: 43
        Count: 1
> HCI Event: Number of Completed Pac.. (0x13) plen 5  #22712 [hci0] 1664.425040
        Num handles: 1
        Handle: 43
        Count: 1
> ACL Data RX: Handle 43 flags 0x02 dlen 12           #22713 [hci0] 1664.426103
      L2CAP: Connection Request (0x02) ident 18 len 4
        PSM: 3 (0x0003)
        Source CID: 65
< ACL Data TX: Handle 43 flags 0x00 dlen 16           #22714 [hci0] 1664.426186
      L2CAP: Connection Response (0x03) ident 18 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 43 flags 0x00 dlen 27           #22715 [hci0] 1664.426196
      L2CAP: Configure Request (0x04) ident 13 len 19
        Destination CID: 65
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1013
        Option: Retransmission and Flow Control (0x04) [mandatory]
          Mode: Basic (0x00)
          TX window size: 0
          Max transmit: 0
          Retransmission timeout: 0
          Monitor timeout: 0
          Maximum PDU size: 0
> ACL Data RX: Handle 43 flags 0x02 dlen 16           #22716 [hci0] 1664.428804
      L2CAP: Connection Response (0x03) ident 12 len 8
        Destination CID: 66
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
*snip*

Fix is to check that channel is in state BT_DISCONN before deleting the
channel.

This bug was found while fuzzing Bluez's OBEX implementation using
Synopsys Defensics.

Reported-by: Matti Kamunen <matti.kamunen@synopsys.com>
Reported-by: Ari Timonen <ari.timonen@synopsys.com>
Signed-off-by: Matias Karhumaa <matias.karhumaa@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
popcornmix pushed a commit that referenced this issue Nov 22, 2021
[ Upstream commit 285f68a ]

The following issue is observed with CONFIG_DEBUG_PREEMPT when KVM loads:

 KVM: vmx: using Hyper-V Enlightened VMCS
 BUG: using smp_processor_id() in preemptible [00000000] code: systemd-udevd/488
 caller is set_hv_tscchange_cb+0x16/0x80
 CPU: 1 PID: 488 Comm: systemd-udevd Not tainted 5.15.0-rc5+ #396
 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019
 Call Trace:
  dump_stack_lvl+0x6a/0x9a
  check_preemption_disabled+0xde/0xe0
  ? kvm_gen_update_masterclock+0xd0/0xd0 [kvm]
  set_hv_tscchange_cb+0x16/0x80
  kvm_arch_init+0x23f/0x290 [kvm]
  kvm_init+0x30/0x310 [kvm]
  vmx_init+0xaf/0x134 [kvm_intel]
  ...

set_hv_tscchange_cb() can get preempted in between acquiring
smp_processor_id() and writing to HV_X64_MSR_REENLIGHTENMENT_CONTROL. This
is not an issue by itself: HV_X64_MSR_REENLIGHTENMENT_CONTROL is a
partition-wide MSR and it doesn't matter which particular CPU will be
used to receive reenlightenment notifications. The only real problem can
(in theory) be observed if the CPU whose id was acquired with
smp_processor_id() goes offline before we manage to write to the MSR,
the logic in hv_cpu_die() won't be able to reassign it correctly.

Reported-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20211012155005.1613352-1-vkuznets@redhat.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
popcornmix pushed a commit that referenced this issue Nov 22, 2021
[ Upstream commit 285f68a ]

The following issue is observed with CONFIG_DEBUG_PREEMPT when KVM loads:

 KVM: vmx: using Hyper-V Enlightened VMCS
 BUG: using smp_processor_id() in preemptible [00000000] code: systemd-udevd/488
 caller is set_hv_tscchange_cb+0x16/0x80
 CPU: 1 PID: 488 Comm: systemd-udevd Not tainted 5.15.0-rc5+ #396
 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019
 Call Trace:
  dump_stack_lvl+0x6a/0x9a
  check_preemption_disabled+0xde/0xe0
  ? kvm_gen_update_masterclock+0xd0/0xd0 [kvm]
  set_hv_tscchange_cb+0x16/0x80
  kvm_arch_init+0x23f/0x290 [kvm]
  kvm_init+0x30/0x310 [kvm]
  vmx_init+0xaf/0x134 [kvm_intel]
  ...

set_hv_tscchange_cb() can get preempted in between acquiring
smp_processor_id() and writing to HV_X64_MSR_REENLIGHTENMENT_CONTROL. This
is not an issue by itself: HV_X64_MSR_REENLIGHTENMENT_CONTROL is a
partition-wide MSR and it doesn't matter which particular CPU will be
used to receive reenlightenment notifications. The only real problem can
(in theory) be observed if the CPU whose id was acquired with
smp_processor_id() goes offline before we manage to write to the MSR,
the logic in hv_cpu_die() won't be able to reassign it correctly.

Reported-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20211012155005.1613352-1-vkuznets@redhat.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
popcornmix pushed a commit that referenced this issue Nov 29, 2021
[ Upstream commit 285f68a ]

The following issue is observed with CONFIG_DEBUG_PREEMPT when KVM loads:

 KVM: vmx: using Hyper-V Enlightened VMCS
 BUG: using smp_processor_id() in preemptible [00000000] code: systemd-udevd/488
 caller is set_hv_tscchange_cb+0x16/0x80
 CPU: 1 PID: 488 Comm: systemd-udevd Not tainted 5.15.0-rc5+ #396
 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019
 Call Trace:
  dump_stack_lvl+0x6a/0x9a
  check_preemption_disabled+0xde/0xe0
  ? kvm_gen_update_masterclock+0xd0/0xd0 [kvm]
  set_hv_tscchange_cb+0x16/0x80
  kvm_arch_init+0x23f/0x290 [kvm]
  kvm_init+0x30/0x310 [kvm]
  vmx_init+0xaf/0x134 [kvm_intel]
  ...

set_hv_tscchange_cb() can get preempted in between acquiring
smp_processor_id() and writing to HV_X64_MSR_REENLIGHTENMENT_CONTROL. This
is not an issue by itself: HV_X64_MSR_REENLIGHTENMENT_CONTROL is a
partition-wide MSR and it doesn't matter which particular CPU will be
used to receive reenlightenment notifications. The only real problem can
(in theory) be observed if the CPU whose id was acquired with
smp_processor_id() goes offline before we manage to write to the MSR,
the logic in hv_cpu_die() won't be able to reassign it correctly.

Reported-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20211012155005.1613352-1-vkuznets@redhat.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
nguyenanhgiau pushed a commit to nguyenanhgiau/linux that referenced this issue Jan 5, 2022
[ Upstream commit 285f68a ]

The following issue is observed with CONFIG_DEBUG_PREEMPT when KVM loads:

 KVM: vmx: using Hyper-V Enlightened VMCS
 BUG: using smp_processor_id() in preemptible [00000000] code: systemd-udevd/488
 caller is set_hv_tscchange_cb+0x16/0x80
 CPU: 1 PID: 488 Comm: systemd-udevd Not tainted 5.15.0-rc5+ raspberrypi#396
 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019
 Call Trace:
  dump_stack_lvl+0x6a/0x9a
  check_preemption_disabled+0xde/0xe0
  ? kvm_gen_update_masterclock+0xd0/0xd0 [kvm]
  set_hv_tscchange_cb+0x16/0x80
  kvm_arch_init+0x23f/0x290 [kvm]
  kvm_init+0x30/0x310 [kvm]
  vmx_init+0xaf/0x134 [kvm_intel]
  ...

set_hv_tscchange_cb() can get preempted in between acquiring
smp_processor_id() and writing to HV_X64_MSR_REENLIGHTENMENT_CONTROL. This
is not an issue by itself: HV_X64_MSR_REENLIGHTENMENT_CONTROL is a
partition-wide MSR and it doesn't matter which particular CPU will be
used to receive reenlightenment notifications. The only real problem can
(in theory) be observed if the CPU whose id was acquired with
smp_processor_id() goes offline before we manage to write to the MSR,
the logic in hv_cpu_die() won't be able to reassign it correctly.

Reported-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20211012155005.1613352-1-vkuznets@redhat.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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