Error: NULL_RETURNS (CWE-476): [#def114]
dnsmasq-2.86test7/src/radv.c:748: returned_null: "expand" returns "NULL" (checked 10 out of 11 times).
dnsmasq-2.86test7/src/radv.c:748: var_assigned: Assigning: "p" = "NULL" return value from "expand".
dnsmasq-2.86test7/src/radv.c:749: dereference: Dereferencing a pointer that might be "NULL" "p" when calling "memset". [Note: The source code implementation of the function has been overridden by a builtin model.]
dnsmasq-2.86test7/src/outpacket.c:83: example_checked: Example 1: "expand(len)" has its value checked in "p = expand(len)".
dnsmasq-2.86test7/src/outpacket.c:109: example_checked: Example 2: "expand(1UL)" has its value checked in "p = expand(1UL)".
dnsmasq-2.86test7/src/radv.c:269: example_checked: Example 3: "expand(16UL)" has its value checked in "ra = expand(16UL)".
dnsmasq-2.86test7/src/radv.c:363: example_checked: Example 4: "expand(32UL)" has its value checked in "opt = expand(32UL)".
dnsmasq-2.86test7/src/radv.c:708: example_checked: Example 5: "expand(32UL)" has its value checked in "opt = expand(32UL)".
# 747| int len = (maclen + 9) >> 3;
# 748| unsigned char *p = expand(len << 3);
# 749|-> memset(p, 0, len << 3);
# 750| *p++ = ICMP6_OPT_SOURCE_MAC;
# 751| *p++ = len;
Error: NULL_RETURNS (CWE-476): [#def115]
dnsmasq-2.86test7/src/radv.c:748: returned_null: "expand" returns "NULL" (checked 10 out of 11 times).
dnsmasq-2.86test7/src/radv.c:748: var_assigned: Assigning: "p" = "NULL" return value from "expand".
dnsmasq-2.86test7/src/radv.c:750: dereference: Incrementing a pointer which might be null: "p".
dnsmasq-2.86test7/src/outpacket.c:83: example_checked: Example 1: "expand(len)" has its value checked in "p = expand(len)".
dnsmasq-2.86test7/src/outpacket.c:109: example_checked: Example 2: "expand(1UL)" has its value checked in "p = expand(1UL)".
dnsmasq-2.86test7/src/radv.c:269: example_checked: Example 3: "expand(16UL)" has its value checked in "ra = expand(16UL)".
dnsmasq-2.86test7/src/radv.c:363: example_checked: Example 4: "expand(32UL)" has its value checked in "opt = expand(32UL)".
dnsmasq-2.86test7/src/radv.c:708: example_checked: Example 5: "expand(32UL)" has its value checked in "opt = expand(32UL)".
# 748| unsigned char *p = expand(len << 3);
# 749| memset(p, 0, len << 3);
# 750|-> *p++ = ICMP6_OPT_SOURCE_MAC;
# 751| *p++ = len;
# 752| memcpy(p, mac, maclen);
Fix heap overflow in IPv6 router advertisement code.
This is a potentially serious security hole, as a
crafted RA request can overflow a buffer and crash or
control dnsmasq. Attacker must be on the local network.
The nasty code with static variable in retry_send() which
avoids looping forever needs to be called on success of the syscall,
to reset the static variable.
