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| author | Shivank Garg <shivankg@amd.com> | 2026-08-22 19:22:05 +0000 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2026-09-09 17:51:44 +0530 |
| commit | e873c74132f0c5f1452816cd9bb26208f0bba1e1 (patch) | |
| tree | cc1ce1567f5b982359331863ebd9da38741f8d2e /Documentation/ABI/testing/procfs-diskstats | |
| download | linux-stable-e873c74132f0c5f1452816cd9bb26208f0bba1e1.tar.gz linux-stable-e873c74132f0c5f1452816cd9bb26208f0bba1e1.zip | |
dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()grafted
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 <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'Documentation/ABI/testing/procfs-diskstats')
| -rw-r--r-- | Documentation/ABI/testing/procfs-diskstats | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/procfs-diskstats b/Documentation/ABI/testing/procfs-diskstats new file mode 100644 index 000000000..6a719cf20 --- /dev/null +++ b/Documentation/ABI/testing/procfs-diskstats @@ -0,0 +1,43 @@ +What: /proc/diskstats +Date: February 2008 +Contact: Jerome Marchand <jmarchan@redhat.com> +Description: + The /proc/diskstats file displays the I/O statistics + of block devices. Each line contains the following 14 + fields: + + == =================================== + 1 major number + 2 minor number + 3 device name + 4 reads completed successfully + 5 reads merged + 6 sectors read + 7 time spent reading (ms) + 8 writes completed + 9 writes merged + 10 sectors written + 11 time spent writing (ms) + 12 I/Os currently in progress + 13 time spent doing I/Os (ms) + 14 weighted time spent doing I/Os (ms) + == =================================== + + Kernel 4.18+ appends four more fields for discard + tracking putting the total at 18: + + == =================================== + 15 discards completed successfully + 16 discards merged + 17 sectors discarded + 18 time spent discarding + == =================================== + + Kernel 5.5+ appends two more fields for flush requests: + + == ===================================== + 19 flush requests completed successfully + 20 time spent flushing + == ===================================== + + For more details refer to Documentation/admin-guide/iostats.rst |