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 --- arch/arm/nwfpe/fpopcode.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 arch/arm/nwfpe/fpopcode.c (limited to 'arch/arm/nwfpe/fpopcode.c') diff --git a/arch/arm/nwfpe/fpopcode.c b/arch/arm/nwfpe/fpopcode.c new file mode 100644 index 000000000..c680bf1bb --- /dev/null +++ b/arch/arm/nwfpe/fpopcode.c @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + NetWinder Floating Point Emulator + (c) Rebel.COM, 1998,1999 + + Direct questions, comments to Scott Bambrough + +*/ + +#include "fpa11.h" +#include "softfloat.h" +#include "fpopcode.h" +#include "fpsr.h" +#include "fpmodule.h" +#include "fpmodule.inl" + +#ifdef CONFIG_FPE_NWFPE_XP +const floatx80 floatx80Constant[] = { + { .high = 0x0000, .low = 0x0000000000000000ULL},/* extended 0.0 */ + { .high = 0x3fff, .low = 0x8000000000000000ULL},/* extended 1.0 */ + { .high = 0x4000, .low = 0x8000000000000000ULL},/* extended 2.0 */ + { .high = 0x4000, .low = 0xc000000000000000ULL},/* extended 3.0 */ + { .high = 0x4001, .low = 0x8000000000000000ULL},/* extended 4.0 */ + { .high = 0x4001, .low = 0xa000000000000000ULL},/* extended 5.0 */ + { .high = 0x3ffe, .low = 0x8000000000000000ULL},/* extended 0.5 */ + { .high = 0x4002, .low = 0xa000000000000000ULL},/* extended 10.0 */ +}; +#endif + +const float64 float64Constant[] = { + 0x0000000000000000ULL, /* double 0.0 */ + 0x3ff0000000000000ULL, /* double 1.0 */ + 0x4000000000000000ULL, /* double 2.0 */ + 0x4008000000000000ULL, /* double 3.0 */ + 0x4010000000000000ULL, /* double 4.0 */ + 0x4014000000000000ULL, /* double 5.0 */ + 0x3fe0000000000000ULL, /* double 0.5 */ + 0x4024000000000000ULL /* double 10.0 */ +}; + +const float32 float32Constant[] = { + 0x00000000, /* single 0.0 */ + 0x3f800000, /* single 1.0 */ + 0x40000000, /* single 2.0 */ + 0x40400000, /* single 3.0 */ + 0x40800000, /* single 4.0 */ + 0x40a00000, /* single 5.0 */ + 0x3f000000, /* single 0.5 */ + 0x41200000 /* single 10.0 */ +}; + -- cgit v1.3.1