diff options
| author | Andrey Konovalov <andreyknvl@google.com> | 2017-11-07 17:11:20 +0100 |
|---|---|---|
| committer | Andrey Konovalov <andreyknvl@gmail.com> | 2017-11-08 17:43:40 +0100 |
| commit | dd1609f876256c4305ac71591fed255880fa9ba7 (patch) | |
| tree | 3e20e872b450e35e516e221f52f005a9afdc2b57 /executor/common_linux.h | |
| parent | 784eb9c23c498850bee1bed72914c17906071945 (diff) | |
executor: proceed even if /dev/net/tun is not available
For some racy bugs syzkaller can generate a C reproducer with tun
enabled, when it's not actuallly required to trigger the bug.
Some kernel developers (that don't have CONFIG_TUN=y on their setups)
complain about such C repros.
When tun is not available, instead of exiting, print a message that tun
initialization failed and proceed.
Diffstat (limited to 'executor/common_linux.h')
| -rw-r--r-- | executor/common_linux.h | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/executor/common_linux.h b/executor/common_linux.h index 48c23485b..f1d4239a4 100644 --- a/executor/common_linux.h +++ b/executor/common_linux.h @@ -295,8 +295,15 @@ static void initialize_tun(uint64_t pid) int id = pid; tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK); - if (tunfd == -1) - fail("tun: can't open /dev/net/tun"); + if (tunfd == -1) { +#ifdef SYZ_EXECUTOR + fail("tun: can't open /dev/net/tun\n"); +#else + printf("tun: can't open /dev/net/tun: please enable CONFIG_TUN=y\n"); + printf("otherwise fuzzing or reproducing might not work as intended\n"); + return; +#endif + } char iface[IFNAMSIZ]; snprintf_check(iface, sizeof(iface), "syz%d", id); @@ -358,6 +365,9 @@ static void setup_tun(uint64_t pid, bool enable_tun) #if defined(SYZ_EXECUTOR) || (defined(SYZ_TUN_ENABLE) && (defined(__NR_syz_extract_tcp_res) || defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT))) static int read_tun(char* data, int size) { + if (tunfd < 0) + return -1; + int rv = read(tunfd, data, size); if (rv < 0) { if (errno == EAGAIN) |