diff options
| author | Mans Rullgard <mans@mansr.com> | 2024-04-30 19:27:05 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2024-05-01 11:02:48 +0900 |
| commit | 4756fa529b2f12b7cb8f21fe229b0f6f47190829 (patch) | |
| tree | 2194354007948133fdeb2d28d5be5436e485605d | |
| parent | 7430764f5a85d30314aeef2d5438dff1fb0b1d68 (diff) | |
| download | linux-4756fa529b2f12b7cb8f21fe229b0f6f47190829.tar.gz | |
spi: fix null pointer dereference within spi_sync
If spi_sync() is called with the non-empty queue and the same spi_message
is then reused, the complete callback for the message remains set while
the context is cleared, leading to a null pointer dereference when the
callback is invoked from spi_finalize_current_message().
With function inlining disabled, the call stack might look like this:
_raw_spin_lock_irqsave from complete_with_flags+0x18/0x58
complete_with_flags from spi_complete+0x8/0xc
spi_complete from spi_finalize_current_message+0xec/0x184
spi_finalize_current_message from spi_transfer_one_message+0x2a8/0x474
spi_transfer_one_message from __spi_pump_transfer_message+0x104/0x230
__spi_pump_transfer_message from __spi_transfer_message_noqueue+0x30/0xc4
__spi_transfer_message_noqueue from __spi_sync+0x204/0x248
__spi_sync from spi_sync+0x24/0x3c
spi_sync from mcp251xfd_regmap_crc_read+0x124/0x28c [mcp251xfd]
mcp251xfd_regmap_crc_read [mcp251xfd] from _regmap_raw_read+0xf8/0x154
_regmap_raw_read from _regmap_bus_read+0x44/0x70
_regmap_bus_read from _regmap_read+0x60/0xd8
_regmap_read from regmap_read+0x3c/0x5c
regmap_read from mcp251xfd_alloc_can_err_skb+0x1c/0x54 [mcp251xfd]
mcp251xfd_alloc_can_err_skb [mcp251xfd] from mcp251xfd_irq+0x194/0xe70 [mcp251xfd]
mcp251xfd_irq [mcp251xfd] from irq_thread_fn+0x1c/0x78
irq_thread_fn from irq_thread+0x118/0x1f4
irq_thread from kthread+0xd8/0xf4
kthread from ret_from_fork+0x14/0x28
Fix this by also setting message->complete to NULL when the transfer is
complete.
Fixes: ae7d2346dc89 ("spi: Don't use the message queue if possible in spi_sync")
Signed-off-by: Mans Rullgard <mans@mansr.com>
Link: https://lore.kernel.org/r/20240430182705.13019-1-mans@mansr.com
Signed-off-by: Mark Brown <broonie@kernel.org>
| -rw-r--r-- | drivers/spi/spi.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ff75838c1b5df..a2c467d9e92f5 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -4523,6 +4523,7 @@ static int __spi_sync(struct spi_device *spi, struct spi_message *message) wait_for_completion(&done); status = message->status; } + message->complete = NULL; message->context = NULL; return status; |