In ata_host_alloc_pinfo(), when ppi[j] is NULL (line 6184), pi is NULL. In this case, pi is used on lines 6187-6195: ap->pio_mask = pi->pio_mask; ap->mwdma_mask = pi->mwdma_mask; ... Thus, possible null-pointer dereferences may occur. To fix these possible bugs, when ppi[j] is NULL, the loop continues, and "j++" is moved to the loop's regulator. These bugs are found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx> --- drivers/ata/libata-core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 28c492be0a57..dabfa50dfbbe 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -6178,11 +6178,13 @@ struct ata_host *ata_host_alloc_pinfo(struct device *dev, if (!host) return NULL; - for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++) { + for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++, j++) { struct ata_port *ap = host->ports[i]; if (ppi[j]) - pi = ppi[j++]; + pi = ppi[j]; + else + continue; ap->pio_mask = pi->pio_mask; ap->mwdma_mask = pi->mwdma_mask; -- 2.17.0