Keyboard backlight on Dell E7470 not adjustable from /sys entry #407

arcivanov · 2017-04-23T04:54:40Z

https://bugzilla.kernel.org/show_bug.cgi?id=191731
https://bugzilla.redhat.com/show_bug.cgi?id=1436686

Also fixes
dell_laptop: Setting old previous keyboard state failed
https://bugzilla.kernel.org/show_bug.cgi?id=194081

The issue is actually quite trivial. Byte 3 of kbd_state
on some machines contains "timeout_ac". If this byte is simply
set to 0 the result is failed state set. The "timeout_ac" is not
interpreted in any way, but it is now preserved in order to ensure
the LED state changes go through.

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arcivanov · 2017-04-23T05:07:59Z

@pali @superm1 I'll cross post this into the mailing list per notice above but I will leave this here for your review as well to speed things up.

https://bugzilla.kernel.org/show_bug.cgi?id=191731 https://bugzilla.redhat.com/show_bug.cgi?id=1436686 Also fixes dell_laptop: Setting old previous keyboard state failed https://bugzilla.kernel.org/show_bug.cgi?id=194081 The issue is actually quite trivial. Byte 3 of kbd_state on some machines contains "timeout_ac". If this byte is simply set to 0 the result is failed state set. The "timeout_ac" is not interpreted in any way, but it is now preserved in order to ensure the LED state changes go through.

AraHaan · 2017-04-23T18:07:52Z

Does the Inspiron 1545 have this issue as well? If so, I can test those changes as I am currently useing that as well (I had to swap out it's T3400 CPU for an P8800 though).

I have also been looking for somone to help me make open source bios for it to that can replace the original and out of date intel bios that can also be buggy at times. (And I do for 1 of the plans increase the max amount of memory it can read (up to 16 or 32 GB's of RAM), increase max HDD space it can read and pretty much all I want to bios to do different than the intel bios for now and make it open sourced)

arcivanov · 2017-04-23T18:21:39Z

@AraHaan I wouldn't know regarding your specific model (Inspiron 9550/60, Precision 7510/20 and the other systems in the modern lineup are definitively affected) but if you were getting either one of these error messages or both then this patch definitely fixes the issue:

[    5.536399] dell_laptop: Setting old previous keyboard state failed
[    5.536434] leds dell::kbd_backlight: Setting an LED's brightness failed (-6)

Additionally you can verify that writing 0 to the /sys/devices/platform/dell-laptop/leds/dell::kbd_backlight/brightness while root will not result in a permission denied and should extinguish keyboard backlight.

arcivanov · 2017-04-23T18:29:33Z

Patchwork: https://patchwork.kernel.org/patch/9694529/

arcivanov · 2017-04-23T20:15:23Z

This patch supersedes mine: https://patchwork.kernel.org/patch/9695271/

The err_remove_chip block is too coarse, and may perform cleanup that must not be done. E.g. if of_gpiochip_add() fails, of_gpiochip_remove() is still called, causing: OF: ERROR: Bad of_node_put() on /soc/gpio@e6050000 CPU: 1 PID: 20 Comm: kworker/1:1 Not tainted 5.1.0-rc2-koelsch+ #407 Hardware name: Generic R-Car Gen2 (Flattened Device Tree) Workqueue: events deferred_probe_work_func [<c020ec74>] (unwind_backtrace) from [<c020ae58>] (show_stack+0x10/0x14) [<c020ae58>] (show_stack) from [<c07c1224>] (dump_stack+0x7c/0x9c) [<c07c1224>] (dump_stack) from [<c07c5a80>] (kobject_put+0x94/0xbc) [<c07c5a80>] (kobject_put) from [<c0470420>] (gpiochip_add_data_with_key+0x8d8/0xa3c) [<c0470420>] (gpiochip_add_data_with_key) from [<c0473738>] (gpio_rcar_probe+0x1d4/0x314) [<c0473738>] (gpio_rcar_probe) from [<c052fca8>] (platform_drv_probe+0x48/0x94) and later, if a GPIO consumer tries to use a GPIO from a failed controller: WARNING: CPU: 0 PID: 1 at lib/refcount.c:156 kobject_get+0x38/0x4c refcount_t: increment on 0; use-after-free. Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.1.0-rc2-koelsch+ #407 Hardware name: Generic R-Car Gen2 (Flattened Device Tree) [<c020ec74>] (unwind_backtrace) from [<c020ae58>] (show_stack+0x10/0x14) [<c020ae58>] (show_stack) from [<c07c1224>] (dump_stack+0x7c/0x9c) [<c07c1224>] (dump_stack) from [<c0221580>] (__warn+0xd0/0xec) [<c0221580>] (__warn) from [<c02215e0>] (warn_slowpath_fmt+0x44/0x6c) [<c02215e0>] (warn_slowpath_fmt) from [<c07c58fc>] (kobject_get+0x38/0x4c) [<c07c58fc>] (kobject_get) from [<c068b3ec>] (of_node_get+0x14/0x1c) [<c068b3ec>] (of_node_get) from [<c0686f24>] (of_find_node_by_phandle+0xc0/0xf0) [<c0686f24>] (of_find_node_by_phandle) from [<c0686fbc>] (of_phandle_iterator_next+0x68/0x154) [<c0686fbc>] (of_phandle_iterator_next) from [<c0687fe4>] (__of_parse_phandle_with_args+0x40/0xd0) [<c0687fe4>] (__of_parse_phandle_with_args) from [<c0688204>] (of_parse_phandle_with_args_map+0x100/0x3ac) [<c0688204>] (of_parse_phandle_with_args_map) from [<c0471240>] (of_get_named_gpiod_flags+0x38/0x380) [<c0471240>] (of_get_named_gpiod_flags) from [<c046f864>] (gpiod_get_from_of_node+0x24/0xd8) [<c046f864>] (gpiod_get_from_of_node) from [<c0470aa4>] (devm_fwnode_get_index_gpiod_from_child+0xa0/0x144) [<c0470aa4>] (devm_fwnode_get_index_gpiod_from_child) from [<c05f425c>] (gpio_keys_probe+0x418/0x7bc) [<c05f425c>] (gpio_keys_probe) from [<c052fca8>] (platform_drv_probe+0x48/0x94) Fix this by splitting the cleanup block, and adding a missing call to gpiochip_irqchip_remove(). Fixes: 28355f8 ("gpio: defer probe if pinctrl cannot be found") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

[ Upstream commit 3577989 ] The err_remove_chip block is too coarse, and may perform cleanup that must not be done. E.g. if of_gpiochip_add() fails, of_gpiochip_remove() is still called, causing: OF: ERROR: Bad of_node_put() on /soc/gpio@e6050000 CPU: 1 PID: 20 Comm: kworker/1:1 Not tainted 5.1.0-rc2-koelsch+ torvalds#407 Hardware name: Generic R-Car Gen2 (Flattened Device Tree) Workqueue: events deferred_probe_work_func [<c020ec74>] (unwind_backtrace) from [<c020ae58>] (show_stack+0x10/0x14) [<c020ae58>] (show_stack) from [<c07c1224>] (dump_stack+0x7c/0x9c) [<c07c1224>] (dump_stack) from [<c07c5a80>] (kobject_put+0x94/0xbc) [<c07c5a80>] (kobject_put) from [<c0470420>] (gpiochip_add_data_with_key+0x8d8/0xa3c) [<c0470420>] (gpiochip_add_data_with_key) from [<c0473738>] (gpio_rcar_probe+0x1d4/0x314) [<c0473738>] (gpio_rcar_probe) from [<c052fca8>] (platform_drv_probe+0x48/0x94) and later, if a GPIO consumer tries to use a GPIO from a failed controller: WARNING: CPU: 0 PID: 1 at lib/refcount.c:156 kobject_get+0x38/0x4c refcount_t: increment on 0; use-after-free. Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.1.0-rc2-koelsch+ torvalds#407 Hardware name: Generic R-Car Gen2 (Flattened Device Tree) [<c020ec74>] (unwind_backtrace) from [<c020ae58>] (show_stack+0x10/0x14) [<c020ae58>] (show_stack) from [<c07c1224>] (dump_stack+0x7c/0x9c) [<c07c1224>] (dump_stack) from [<c0221580>] (__warn+0xd0/0xec) [<c0221580>] (__warn) from [<c02215e0>] (warn_slowpath_fmt+0x44/0x6c) [<c02215e0>] (warn_slowpath_fmt) from [<c07c58fc>] (kobject_get+0x38/0x4c) [<c07c58fc>] (kobject_get) from [<c068b3ec>] (of_node_get+0x14/0x1c) [<c068b3ec>] (of_node_get) from [<c0686f24>] (of_find_node_by_phandle+0xc0/0xf0) [<c0686f24>] (of_find_node_by_phandle) from [<c0686fbc>] (of_phandle_iterator_next+0x68/0x154) [<c0686fbc>] (of_phandle_iterator_next) from [<c0687fe4>] (__of_parse_phandle_with_args+0x40/0xd0) [<c0687fe4>] (__of_parse_phandle_with_args) from [<c0688204>] (of_parse_phandle_with_args_map+0x100/0x3ac) [<c0688204>] (of_parse_phandle_with_args_map) from [<c0471240>] (of_get_named_gpiod_flags+0x38/0x380) [<c0471240>] (of_get_named_gpiod_flags) from [<c046f864>] (gpiod_get_from_of_node+0x24/0xd8) [<c046f864>] (gpiod_get_from_of_node) from [<c0470aa4>] (devm_fwnode_get_index_gpiod_from_child+0xa0/0x144) [<c0470aa4>] (devm_fwnode_get_index_gpiod_from_child) from [<c05f425c>] (gpio_keys_probe+0x418/0x7bc) [<c05f425c>] (gpio_keys_probe) from [<c052fca8>] (platform_drv_probe+0x48/0x94) Fix this by splitting the cleanup block, and adding a missing call to gpiochip_irqchip_remove(). Fixes: 28355f8 ("gpio: defer probe if pinctrl cannot be found") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

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 torvalds#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 torvalds#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 torvalds#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 torvalds#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 torvalds#397 [hci1] 10.752391 Num handles: 1 Handle: 43 Count: 1 > HCI Event: Number of Completed Packets (0x13) plen 5 torvalds#398 [hci1] 10.753394 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 12 torvalds#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 torvalds#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 torvalds#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 torvalds#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 torvalds#403 [hci1] 10.759386 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 12 torvalds#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 torvalds#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 torvalds#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 torvalds#407 [hci1] 10.761399 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 16 torvalds#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>

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 torvalds#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 torvalds#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 torvalds#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 torvalds#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 torvalds#397 [hci1] 10.752391 Num handles: 1 Handle: 43 Count: 1 > HCI Event: Number of Completed Packets (0x13) plen 5 torvalds#398 [hci1] 10.753394 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 12 torvalds#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 torvalds#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 torvalds#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 torvalds#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 torvalds#403 [hci1] 10.759386 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 12 torvalds#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 torvalds#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 torvalds#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 torvalds#407 [hci1] 10.761399 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 16 torvalds#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>

[ 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 torvalds#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 torvalds#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 torvalds#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 torvalds#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 torvalds#397 [hci1] 10.752391 Num handles: 1 Handle: 43 Count: 1 > HCI Event: Number of Completed Packets (0x13) plen 5 torvalds#398 [hci1] 10.753394 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 12 torvalds#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 torvalds#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 torvalds#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 torvalds#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 torvalds#403 [hci1] 10.759386 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 12 torvalds#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 torvalds#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 torvalds#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 torvalds#407 [hci1] 10.761399 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 16 torvalds#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>

[ 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>

[ 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 torvalds#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 torvalds#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 torvalds#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 torvalds#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 torvalds#397 [hci1] 10.752391 Num handles: 1 Handle: 43 Count: 1 > HCI Event: Number of Completed Packets (0x13) plen 5 torvalds#398 [hci1] 10.753394 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 12 torvalds#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 torvalds#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 torvalds#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 torvalds#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 torvalds#403 [hci1] 10.759386 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 12 torvalds#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 torvalds#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 torvalds#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 torvalds#407 [hci1] 10.761399 Num handles: 1 Handle: 43 Count: 1 > ACL Data RX: Handle 43 flags 0x02 dlen 16 torvalds#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>

rmnet_get_port() internally calls rcu_dereference_rtnl(), which checks RTNL. But rmnet_get_port() could be called by packet path. The packet path is not protected by RTNL. So, the suspicious RCU usage problem occurs. Test commands: ip netns add nst ip link add veth0 type veth peer name veth1 ip link set veth1 netns nst ip link add rmnet0 link veth0 type rmnet mux_id 1 ip netns exec nst ip link add rmnet1 link veth1 type rmnet mux_id 1 ip netns exec nst ip link set veth1 up ip netns exec nst ip link set rmnet1 up ip netns exec nst ip a a 192.168.100.2/24 dev rmnet1 ip link set veth0 up ip link set rmnet0 up ip a a 192.168.100.1/24 dev rmnet0 ping 192.168.100.2 Splat looks like: [ 339.775811][ T969] ============================= [ 339.777204][ T969] WARNING: suspicious RCU usage [ 339.778188][ T969] 5.5.0+ torvalds#407 Not tainted [ 339.779123][ T969] ----------------------------- [ 339.780100][ T969] drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c:389 suspicious rcu_dereference_check() usage! [ 339.781943][ T969] [ 339.781943][ T969] other info that might help us debug this: [ 339.781943][ T969] [ 339.783475][ T969] [ 339.783475][ T969] rcu_scheduler_active = 2, debug_locks = 1 [ 339.784656][ T969] 5 locks held by ping/969: [ 339.785406][ T969] #0: ffff88804cb897f0 (sk_lock-AF_INET){+.+.}, at: raw_sendmsg+0xab8/0x2980 [ 339.786766][ T969] #1: ffffffff92925460 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x243/0x2150 [ 339.788308][ T969] #2: ffffffff92925460 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x213/0x2e10 [ 339.790662][ T969] #3: ffff88805a924158 (&dev->qdisc_running_key#3){+...}, at: ip_finish_output2+0x714/0x2150 [ 339.792072][ T969] #4: ffff88805b4fdc98 (&dev->qdisc_xmit_lock_key#3){+.-.}, at: sch_direct_xmit+0x1e2/0x1020 [ 339.793445][ T969] [ 339.793445][ T969] stack backtrace: [ 339.794691][ T969] CPU: 3 PID: 969 Comm: ping Not tainted 5.5.0+ torvalds#407 [ 339.795946][ T969] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 339.797621][ T969] Call Trace: [ 339.798249][ T969] dump_stack+0x96/0xdb [ 339.798847][ T969] rmnet_get_port.part.9+0x76/0x80 [rmnet] [ 339.799583][ T969] rmnet_egress_handler+0x107/0x420 [rmnet] [ 339.800350][ T969] ? sch_direct_xmit+0x1e2/0x1020 [ 339.801027][ T969] rmnet_vnd_start_xmit+0x3d/0xa0 [rmnet] [ 339.801784][ T969] dev_hard_start_xmit+0x160/0x740 [ 339.802667][ T969] sch_direct_xmit+0x265/0x1020 [ ... ] Fixes: ceed73a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation") Signed-off-by: Taehee Yoo <ap420073@gmail.com>

When removing the device we call blkdev_put() on the device once we've removed it, and because we have an EXCL open we need to take the ->open_mutex on the block device to clean it up. Unfortunately during device remove we are holding the sb writers lock, which results in the following lockdep splat ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#407 Not tainted ------------------------------------------------------ losetup/11595 is trying to acquire lock: ffff973ac35dd138 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_put+0x3a/0x220 btrfs_rm_device.cold+0x62/0xe5 btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11595: #0: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 0 PID: 11595 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#407 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc21255d4cb So instead save the bdev and do the put once we've dropped the sb writers lock in order to avoid the lockdep recursion. Signed-off-by: Josef Bacik <josef@toxicpanda.com>

When removing the device we call blkdev_put() on the device once we've removed it, and because we have an EXCL open we need to take the ->open_mutex on the block device to clean it up. Unfortunately during device remove we are holding the sb writers lock, which results in the following lockdep splat ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#407 Not tainted ------------------------------------------------------ losetup/11595 is trying to acquire lock: ffff973ac35dd138 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_put+0x3a/0x220 btrfs_rm_device.cold+0x62/0xe5 btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11595: #0: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 0 PID: 11595 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#407 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc21255d4cb So instead save the bdev and do the put once we've dropped the sb writers lock in order to avoid the lockdep recursion. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>

When removing the device we call blkdev_put() on the device once we've removed it, and because we have an EXCL open we need to take the ->open_mutex on the block device to clean it up. Unfortunately during device remove we are holding the sb writers lock, which results in the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#407 Not tainted ------------------------------------------------------ losetup/11595 is trying to acquire lock: ffff973ac35dd138 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_put+0x3a/0x220 btrfs_rm_device.cold+0x62/0xe5 btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11595: #0: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 0 PID: 11595 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#407 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc21255d4cb So instead save the bdev and do the put once we've dropped the sb writers lock in order to avoid the lockdep recursion. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

[ Upstream commit 3fa421d ] When removing the device we call blkdev_put() on the device once we've removed it, and because we have an EXCL open we need to take the ->open_mutex on the block device to clean it up. Unfortunately during device remove we are holding the sb writers lock, which results in the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.14.0-rc2+ torvalds#407 Not tainted ------------------------------------------------------ losetup/11595 is trying to acquire lock: ffff973ac35dd138 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0 but task is already holding lock: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&lo->lo_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 lo_open+0x28/0x60 [loop] blkdev_get_whole+0x25/0xf0 blkdev_get_by_dev.part.0+0x168/0x3c0 blkdev_open+0xd2/0xe0 do_dentry_open+0x161/0x390 path_openat+0x3cc/0xa20 do_filp_open+0x96/0x120 do_sys_openat2+0x7b/0x130 __x64_sys_openat+0x46/0x70 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock+0x7d/0x750 blkdev_put+0x3a/0x220 btrfs_rm_device.cold+0x62/0xe5 btrfs_ioctl+0x2a31/0x2e70 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#12){.+.+}-{0:0}: lo_write_bvec+0xc2/0x240 [loop] loop_process_work+0x238/0xd00 [loop] process_one_work+0x26b/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: process_one_work+0x245/0x560 worker_thread+0x55/0x3c0 kthread+0x140/0x160 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 flush_workqueue+0x91/0x5e0 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 1 lock held by losetup/11595: #0: ffff973ac9812c68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop] stack backtrace: CPU: 0 PID: 11595 Comm: losetup Not tainted 5.14.0-rc2+ torvalds#407 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x57/0x72 check_noncircular+0xcf/0xf0 ? stack_trace_save+0x3b/0x50 __lock_acquire+0x10ea/0x1d90 lock_acquire+0xb5/0x2b0 ? flush_workqueue+0x67/0x5e0 ? lockdep_init_map_type+0x47/0x220 flush_workqueue+0x91/0x5e0 ? flush_workqueue+0x67/0x5e0 ? verify_cpu+0xf0/0x100 drain_workqueue+0xa0/0x110 destroy_workqueue+0x36/0x250 __loop_clr_fd+0x9a/0x660 [loop] ? blkdev_ioctl+0x8d/0x2a0 block_ioctl+0x3f/0x50 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc21255d4cb So instead save the bdev and do the put once we've dropped the sb writers lock in order to avoid the lockdep recursion. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

…-fixes WARNING: Block comments use a trailing */ on a separate line torvalds#407: FILE: arch/s390/mm/fault.c:459: + * mmap_lock has not been released */ total: 0 errors, 1 warnings, 444 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-remove-redundant-check-about-fault_flag_allow_retry-bit.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

…-fixes WARNING: Block comments use a trailing */ on a separate line torvalds#407: FILE: arch/s390/mm/fault.c:459: + * mmap_lock has not been released */ total: 0 errors, 1 warnings, 444 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-remove-redundant-check-about-fault_flag_allow_retry-bit.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

…-fixes WARNING: Block comments use a trailing */ on a separate line torvalds#407: FILE: arch/s390/mm/fault.c:459: + * mmap_lock has not been released */ total: 0 errors, 1 warnings, 444 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-remove-redundant-check-about-fault_flag_allow_retry-bit.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Mark Brown <broonie@kernel.org>

…-fixes WARNING: Block comments use a trailing */ on a separate line torvalds#407: FILE: arch/s390/mm/fault.c:459: + * mmap_lock has not been released */ total: 0 errors, 1 warnings, 444 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-remove-redundant-check-about-fault_flag_allow_retry-bit.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

PD#151225: driver defect clean up: torvalds#228 torvalds#262 torvalds#354 torvalds#407 torvalds#442 torvalds#445 torvalds#461 torvalds#576 torvalds#580 torvalds#598 torvalds#599 torvalds#615 torvalds#616 torvalds#671 torvalds#756 torvalds#760 torvalds#874 Change-Id: I1bc47c3e30ecfa1ca44e53f91201aa4e09ff19f5 Signed-off-by: Bencheng Jing <bencheng.jing@amlogic.com>

arcivanov force-pushed the bug_191731 branch from ea33b90 to 7639d16 Compare April 23, 2017 05:11

arcivanov force-pushed the bug_191731 branch 2 times, most recently from 006964f to 250168a Compare April 23, 2017 05:24

arcivanov closed this Apr 23, 2017

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Keyboard backlight on Dell E7470 not adjustable from /sys entry #407

Keyboard backlight on Dell E7470 not adjustable from /sys entry #407

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Keyboard backlight on Dell E7470 not adjustable from /sys entry #407

Keyboard backlight on Dell E7470 not adjustable from /sys entry #407

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