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 --- drivers/md/bcache/features.h | 113 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 113 insertions(+) create mode 100644 drivers/md/bcache/features.h (limited to 'drivers/md/bcache/features.h') diff --git a/drivers/md/bcache/features.h b/drivers/md/bcache/features.h new file mode 100644 index 000000000..09161b89c --- /dev/null +++ b/drivers/md/bcache/features.h @@ -0,0 +1,113 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _BCACHE_FEATURES_H +#define _BCACHE_FEATURES_H + +#include +#include + +#include "bcache_ondisk.h" + +#define BCH_FEATURE_COMPAT 0 +#define BCH_FEATURE_RO_COMPAT 1 +#define BCH_FEATURE_INCOMPAT 2 +#define BCH_FEATURE_TYPE_MASK 0x03 + +/* Feature set definition */ +/* Incompat feature set */ +/* 32bit bucket size, obsoleted */ +#define BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET 0x0001 +/* real bucket size is (1 << bucket_size) */ +#define BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE 0x0002 + +#define BCH_FEATURE_COMPAT_SUPP 0 +#define BCH_FEATURE_RO_COMPAT_SUPP 0 +#define BCH_FEATURE_INCOMPAT_SUPP (BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET| \ + BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE) + +#define BCH_HAS_COMPAT_FEATURE(sb, mask) \ + ((sb)->feature_compat & (mask)) +#define BCH_HAS_RO_COMPAT_FEATURE(sb, mask) \ + ((sb)->feature_ro_compat & (mask)) +#define BCH_HAS_INCOMPAT_FEATURE(sb, mask) \ + ((sb)->feature_incompat & (mask)) + +#define BCH_FEATURE_COMPAT_FUNCS(name, flagname) \ +static inline int bch_has_feature_##name(struct cache_sb *sb) \ +{ \ + if (sb->version < BCACHE_SB_VERSION_CDEV_WITH_FEATURES) \ + return 0; \ + return (((sb)->feature_compat & \ + BCH##_FEATURE_COMPAT_##flagname) != 0); \ +} \ +static inline void bch_set_feature_##name(struct cache_sb *sb) \ +{ \ + (sb)->feature_compat |= \ + BCH##_FEATURE_COMPAT_##flagname; \ +} \ +static inline void bch_clear_feature_##name(struct cache_sb *sb) \ +{ \ + (sb)->feature_compat &= \ + ~BCH##_FEATURE_COMPAT_##flagname; \ +} + +#define BCH_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ +static inline int bch_has_feature_##name(struct cache_sb *sb) \ +{ \ + if (sb->version < BCACHE_SB_VERSION_CDEV_WITH_FEATURES) \ + return 0; \ + return (((sb)->feature_ro_compat & \ + BCH##_FEATURE_RO_COMPAT_##flagname) != 0); \ +} \ +static inline void bch_set_feature_##name(struct cache_sb *sb) \ +{ \ + (sb)->feature_ro_compat |= \ + BCH##_FEATURE_RO_COMPAT_##flagname; \ +} \ +static inline void bch_clear_feature_##name(struct cache_sb *sb) \ +{ \ + (sb)->feature_ro_compat &= \ + ~BCH##_FEATURE_RO_COMPAT_##flagname; \ +} + +#define BCH_FEATURE_INCOMPAT_FUNCS(name, flagname) \ +static inline int bch_has_feature_##name(struct cache_sb *sb) \ +{ \ + if (sb->version < BCACHE_SB_VERSION_CDEV_WITH_FEATURES) \ + return 0; \ + return (((sb)->feature_incompat & \ + BCH##_FEATURE_INCOMPAT_##flagname) != 0); \ +} \ +static inline void bch_set_feature_##name(struct cache_sb *sb) \ +{ \ + (sb)->feature_incompat |= \ + BCH##_FEATURE_INCOMPAT_##flagname; \ +} \ +static inline void bch_clear_feature_##name(struct cache_sb *sb) \ +{ \ + (sb)->feature_incompat &= \ + ~BCH##_FEATURE_INCOMPAT_##flagname; \ +} + +BCH_FEATURE_INCOMPAT_FUNCS(obso_large_bucket, OBSO_LARGE_BUCKET); +BCH_FEATURE_INCOMPAT_FUNCS(large_bucket, LOG_LARGE_BUCKET_SIZE); + +static inline bool bch_has_unknown_compat_features(struct cache_sb *sb) +{ + return ((sb->feature_compat & ~BCH_FEATURE_COMPAT_SUPP) != 0); +} + +static inline bool bch_has_unknown_ro_compat_features(struct cache_sb *sb) +{ + return ((sb->feature_ro_compat & ~BCH_FEATURE_RO_COMPAT_SUPP) != 0); +} + +static inline bool bch_has_unknown_incompat_features(struct cache_sb *sb) +{ + return ((sb->feature_incompat & ~BCH_FEATURE_INCOMPAT_SUPP) != 0); +} + +int bch_print_cache_set_feature_compat(struct cache_set *c, char *buf, int size); +int bch_print_cache_set_feature_ro_compat(struct cache_set *c, char *buf, int size); +int bch_print_cache_set_feature_incompat(struct cache_set *c, char *buf, int size); + +#endif -- cgit v1.3.1