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| author |   Nitin Gote <nitin.r.gote@intel.com> | 2025-07-18 16:20:51 +0530 |
|---|---|---|
| committer |   Thomas Zimmermann <tzimmermann@suse.de> | 2025-08-11 17:26:38 +0200 |
| commit | 5634c8cb298a7146b4e38873473e280b50e27a2c (patch) | |
| tree | 96db837ffc32573063b2798502679c1eff7f7f43 | |
| parent | drm/tests: Fix drm_test_fb_xrgb8888_to_xrgb2101010() on big-endian (diff) | |
| download | wireguard-linux-5634c8cb298a7146b4e38873473e280b50e27a2c.tar.xz wireguard-linux-5634c8cb298a7146b4e38873473e280b50e27a2c.zip | |
iosys-map: Fix undefined behavior in iosys_map_clear()
The current iosys_map_clear() implementation reads the potentially
uninitialized 'is_iomem' boolean field to decide which union member
to clear. This causes undefined behavior when called on uninitialized
structures, as 'is_iomem' may contain garbage values like 0xFF.
UBSAN detects this as:
UBSAN: invalid-load in include/linux/iosys-map.h:267
load of value 255 is not a valid value for type '_Bool'
Fix by unconditionally clearing the entire structure with memset(),
eliminating the need to read uninitialized data and ensuring all
fields are set to known good values.
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14639
Fixes: 01fd30da0474 ("dma-buf: Add struct dma-buf-map for storing struct dma_buf.vaddr_ptr")
Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250718105051.2709487-1-nitin.r.gote@intel.com
| -rw-r--r-- | include/linux/iosys-map.h | 7 |
1 files changed, 1 insertions, 6 deletions
diff --git a/include/linux/iosys-map.h b/include/linux/iosys-map.h index 4696abfd311c..3e85afe794c0 100644 --- a/include/linux/iosys-map.h +++ b/include/linux/iosys-map.h @@ -264,12 +264,7 @@ static inline bool iosys_map_is_set(const struct iosys_map *map) */ static inline void iosys_map_clear(struct iosys_map *map) { - if (map->is_iomem) { - map->vaddr_iomem = NULL; - map->is_iomem = false; - } else { - map->vaddr = NULL; - } + memset(map, 0, sizeof(*map)); } /** |