diff options
| author | Matthew R. Ochs <mochs@nvidia.com> | 2024-05-22 15:06:40 +0300 |
|---|---|---|
| committer | Jarkko Sakkinen <jarkko@kernel.org> | 2024-05-28 13:03:57 +0300 |
| commit | 195aba96b854dd664768f382cd1db375d8181f88 (patch) | |
| tree | 696d793032d6c1268ed7084e83674838248ce44d /drivers/char | |
| parent | 2bfcfd584ff5ccc8bb7acde19b42570414bf880b (diff) | |
| download | linux-195aba96b854dd664768f382cd1db375d8181f88.tar.xz | |
tpm_tis_spi: Account for SPI header when allocating TPM SPI xfer buffer
The TPM SPI transfer mechanism uses MAX_SPI_FRAMESIZE for computing the
maximum transfer length and the size of the transfer buffer. As such, it
does not account for the 4 bytes of header that prepends the SPI data
frame. This can result in out-of-bounds accesses and was confirmed with
KASAN.
Introduce SPI_HDRSIZE to account for the header and use to allocate the
transfer buffer.
Fixes: a86a42ac2bd6 ("tpm_tis_spi: Add hardware wait polling")
Signed-off-by: Matthew R. Ochs <mochs@nvidia.com>
Tested-by: Carol Soto <csoto@nvidia.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/tpm/tpm_tis_spi_main.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/char/tpm/tpm_tis_spi_main.c b/drivers/char/tpm/tpm_tis_spi_main.c index 3f9eaf27b41b..c9eca24bbad4 100644 --- a/drivers/char/tpm/tpm_tis_spi_main.c +++ b/drivers/char/tpm/tpm_tis_spi_main.c @@ -37,6 +37,7 @@ #include "tpm_tis_spi.h" #define MAX_SPI_FRAMESIZE 64 +#define SPI_HDRSIZE 4 /* * TCG SPI flow control is documented in section 6.4 of the spec[1]. In short, @@ -247,7 +248,7 @@ static int tpm_tis_spi_write_bytes(struct tpm_tis_data *data, u32 addr, int tpm_tis_spi_init(struct spi_device *spi, struct tpm_tis_spi_phy *phy, int irq, const struct tpm_tis_phy_ops *phy_ops) { - phy->iobuf = devm_kmalloc(&spi->dev, MAX_SPI_FRAMESIZE, GFP_KERNEL); + phy->iobuf = devm_kmalloc(&spi->dev, SPI_HDRSIZE + MAX_SPI_FRAMESIZE, GFP_KERNEL); if (!phy->iobuf) return -ENOMEM; |