From: Sergey Shtylyov Date: Sat, 21 May 2022 20:34:10 +0000 (+0300) Subject: ata: libata-core: fix NULL pointer deref in ata_host_alloc_pinfo() X-Git-Tag: v5.19-rc2~22^2~5 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=bf476fe22aa1851bab4728e0c49025a6a0bea307;p=linux-block.git ata: libata-core: fix NULL pointer deref in ata_host_alloc_pinfo() In an unlikely (and probably wrong?) case that the 'ppi' parameter of ata_host_alloc_pinfo() points to an array starting with a NULL pointer, there's going to be a kernel oops as the 'pi' local variable won't get reassigned from the initial value of NULL. Initialize 'pi' instead to '&ata_dummy_port_info' to fix the possible kernel oops for good... Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool. Signed-off-by: Sergey Shtylyov Signed-off-by: Damien Le Moal --- diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 40e816419f48..c214ff928e45 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -5462,7 +5462,7 @@ struct ata_host *ata_host_alloc_pinfo(struct device *dev, const struct ata_port_info * const * ppi, int n_ports) { - const struct ata_port_info *pi; + const struct ata_port_info *pi = &ata_dummy_port_info; struct ata_host *host; int i, j; @@ -5470,7 +5470,7 @@ 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; i < host->n_ports; i++) { struct ata_port *ap = host->ports[i]; if (ppi[j])