From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- .../ABI/testing/sysfs-class-led-trigger-tty | 62 ++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-led-trigger-tty (limited to 'Documentation/ABI/testing/sysfs-class-led-trigger-tty') diff --git a/Documentation/ABI/testing/sysfs-class-led-trigger-tty b/Documentation/ABI/testing/sysfs-class-led-trigger-tty new file mode 100644 index 000000000..308fbc362 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-led-trigger-tty @@ -0,0 +1,62 @@ +What: /sys/class/leds//ttyname +Date: Dec 2020 +KernelVersion: 5.10 +Contact: linux-leds@vger.kernel.org +Description: + Specifies the tty device name of the triggering tty + +What: /sys/class/leds//rx +Date: February 2024 +KernelVersion: 6.8 +Description: + Signal reception (rx) of data on the named tty device. + If set to 0, the LED will not blink on reception. + If set to 1 (default), the LED will blink on reception. + +What: /sys/class/leds//tx +Date: February 2024 +KernelVersion: 6.8 +Description: + Signal transmission (tx) of data on the named tty device. + If set to 0, the LED will not blink on transmission. + If set to 1 (default), the LED will blink on transmission. + +What: /sys/class/leds//cts +Date: February 2024 +KernelVersion: 6.8 +Description: + CTS = Clear To Send + DCE is ready to accept data from the DTE. + If the line state is detected, the LED is switched on. + If set to 0 (default), the LED will not evaluate CTS. + If set to 1, the LED will evaluate CTS. + +What: /sys/class/leds//dsr +Date: February 2024 +KernelVersion: 6.8 +Description: + DSR = Data Set Ready + DCE is ready to receive and send data. + If the line state is detected, the LED is switched on. + If set to 0 (default), the LED will not evaluate DSR. + If set to 1, the LED will evaluate DSR. + +What: /sys/class/leds//dcd +Date: February 2024 +KernelVersion: 6.8 +Description: + DCD = Data Carrier Detect + DTE is receiving a carrier from the DCE. + If the line state is detected, the LED is switched on. + If set to 0 (default), the LED will not evaluate CAR (DCD). + If set to 1, the LED will evaluate CAR (DCD). + +What: /sys/class/leds//rng +Date: February 2024 +KernelVersion: 6.8 +Description: + RNG = Ring Indicator + DCE has detected an incoming ring signal on the telephone + line. If the line state is detected, the LED is switched on. + If set to 0 (default), the LED will not evaluate RNG. + If set to 1, the LED will evaluate RNG. -- cgit v1.3.1