[dpdk-stable] [PATCH v1 1/2] pci: fix allowing underflow when parsing PCI id

[Gaetan Rivet <grive@u256.net>]

The function strtoul will not return ERANGE if the input is negative, as
one might expect.

   0000:-FFFFFFFFFFFFFFFB:00.0

is not a better way to write 0000:05:00.0.
To simplify checking for '-', forbid using spaces before the field value.

   0000: 00:   2c.0

Should not be accepted.

Fixes: af75078fece3 ("first public release")
Cc: stable@dpdk.org
Signed-off-by: Gaetan Rivet <grive@u256.net>
---
 lib/librte_pci/rte_pci.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lib/librte_pci/rte_pci.c b/lib/librte_pci/rte_pci.c
index d1ab6b414..e4ecdc32f 100644
--- a/lib/librte_pci/rte_pci.c
+++ b/lib/librte_pci/rte_pci.c
@@ -35,6 +35,12 @@ get_u8_pciaddr_field(const char *in, void *_u8, char dlm)
 	if (*in == '\0')
 		return NULL;
 
+	/* PCI field starting with spaces is forbidden.
+	 * Negative wrap-around is not reported as an error by strtoul.
+	 */
+	if (*in == ' ' || *in == '-')
+		return NULL;
+
 	errno = 0;
 	val = strtoul(in, &end, 16);
 	if (errno != 0 || end[0] != dlm || val > UINT8_MAX) {
@@ -70,6 +76,12 @@ pci_dbdf_parse(const char *input, struct rte_pci_addr *dev_addr)
 	unsigned long val;
 	char *end;
 
+	/* PCI id starting with spaces is forbidden.
+	 * Negative wrap-around is not reported as an error by strtoul.
+	 */
+	if (*in == ' ' || *in == '-')
+		return EINVAL;
+
 	errno = 0;
 	val = strtoul(in, &end, 16);
 	if (errno != 0 || end[0] != ':' || val > UINT16_MAX)
-- 
2.26.2