The pdc20621_prog_dimm0() calls the pdc20621_i2c_read(), but does not handle the error if the read fails. This could lead to process with invalid data. A proper inplementation can be found in pdc20621_prog_dimm_global(). As mentioned in its commit: bb44e154e25125bef31fa956785e90fccd24610b, the variable spd0 might be used uninitialized when pdc20621_i2c_read() fails. Add error handling to the pdc20621_i2c_read(). If a read operation fails, an error message is logged via dev_err(), and return an under-zero value to represent error situlation. Add error handling to pdc20621_prog_dimm0() in pdc20621_dimm_init(), and return a none-zero value when pdc20621_prog_dimm0() fails. Fixes: 4447d3515616 ("libata: convert the remaining SATA drivers to new init model") Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx> --- drivers/ata/sata_sx4.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/ata/sata_sx4.c b/drivers/ata/sata_sx4.c index a482741eb181..a4027eb2fb66 100644 --- a/drivers/ata/sata_sx4.c +++ b/drivers/ata/sata_sx4.c @@ -1117,9 +1117,14 @@ static int pdc20621_prog_dimm0(struct ata_host *host) mmio += PDC_CHIP0_OFS; for (i = 0; i < ARRAY_SIZE(pdc_i2c_read_data); i++) - pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS, - pdc_i2c_read_data[i].reg, - &spd0[pdc_i2c_read_data[i].ofs]); + if (!pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS, + pdc_i2c_read_data[i].reg, + &spd0[pdc_i2c_read_data[i].ofs])){ + dev_err(host->dev, + "Failed in i2c read at index %d: device=%#x, reg=%#x\n", + i, PDC_DIMM0_SPD_DEV_ADDRESS, pdc_i2c_read_data[i].reg); + return -1; + } data |= (spd0[4] - 8) | ((spd0[21] != 0) << 3) | ((spd0[3]-11) << 4); data |= ((spd0[17] / 4) << 6) | ((spd0[5] / 2) << 7) | @@ -1284,6 +1289,8 @@ static unsigned int pdc20621_dimm_init(struct ata_host *host) /* Programming DIMM0 Module Control Register (index_CID0:80h) */ size = pdc20621_prog_dimm0(host); + if (size < 0) + return 1; dev_dbg(host->dev, "Local DIMM Size = %dMB\n", size); /* Programming DIMM Module Global Control Register (index_CID0:88h) */ -- 2.42.0.windows.2