diff options
| author | Amelie Delaunay <amelie.delaunay@foss.st.com> | 2023-11-06 14:48:32 +0100 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2023-11-24 18:28:25 +0530 |
| commit | 54bed6bafa0f38daf9697af50e3aff5ff1354fe1 (patch) | |
| tree | 3a35c410cae6558acc8b4e342cf7f6d01fe258b8 /drivers/dma | |
| parent | 3448397a47c08c291c3fccb7ac5f0f429fd547e0 (diff) | |
dmaengine: stm32-dma: avoid bitfield overflow assertion
stm32_dma_get_burst() returns a negative error for invalid input, which
gets turned into a large u32 value in stm32_dma_prep_dma_memcpy() that
in turn triggers an assertion because it does not fit into a two-bit field:
drivers/dma/stm32-dma.c: In function 'stm32_dma_prep_dma_memcpy':
include/linux/compiler_types.h:354:38: error: call to '__compiletime_assert_282' declared with attribute error: FIELD_PREP: value too large for the field
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
include/linux/compiler_types.h:335:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler_types.h:354:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
include/linux/bitfield.h:68:3: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(__builtin_constant_p(_val) ? \
^~~~~~~~~~~~~~~~
include/linux/bitfield.h:114:3: note: in expansion of macro '__BF_FIELD_CHECK'
__BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: "); \
^~~~~~~~~~~~~~~~
drivers/dma/stm32-dma.c:1237:4: note: in expansion of macro 'FIELD_PREP'
FIELD_PREP(STM32_DMA_SCR_PBURST_MASK, dma_burst) |
^~~~~~~~~~
As an easy workaround, assume the error can happen, so try to handle this
by failing stm32_dma_prep_dma_memcpy() before the assertion. It replicates
what is done in stm32_dma_set_xfer_param() where stm32_dma_get_burst() is
also used.
Fixes: 1c32d6c37cc2 ("dmaengine: stm32-dma: use bitfield helpers")
Fixes: a2b6103b7a8a ("dmaengine: stm32-dma: Improve memory burst management")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311060135.Q9eMnpCL-lkp@intel.com/
Link: https://lore.kernel.org/r/20231106134832.1470305-1-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/stm32-dma.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c index 72d83cd9ed6b..90857d08a1a7 100644 --- a/drivers/dma/stm32-dma.c +++ b/drivers/dma/stm32-dma.c @@ -1246,8 +1246,8 @@ static struct dma_async_tx_descriptor *stm32_dma_prep_dma_memcpy( enum dma_slave_buswidth max_width; struct stm32_dma_desc *desc; size_t xfer_count, offset; - u32 num_sgs, best_burst, dma_burst, threshold; - int i; + u32 num_sgs, best_burst, threshold; + int dma_burst, i; num_sgs = DIV_ROUND_UP(len, STM32_DMA_ALIGNED_MAX_DATA_ITEMS); desc = kzalloc(struct_size(desc, sg_req, num_sgs), GFP_NOWAIT); @@ -1266,6 +1266,10 @@ static struct dma_async_tx_descriptor *stm32_dma_prep_dma_memcpy( best_burst = stm32_dma_get_best_burst(len, STM32_DMA_MAX_BURST, threshold, max_width); dma_burst = stm32_dma_get_burst(chan, best_burst); + if (dma_burst < 0) { + kfree(desc); + return NULL; + } stm32_dma_clear_reg(&desc->sg_req[i].chan_reg); desc->sg_req[i].chan_reg.dma_scr = |