diff options
author | Alexey Izbyshev <izbyshev@ispras.ru> | 2023-02-27 23:18:02 +0300 |
---|---|---|
committer | Rich Felker <dalias@aerifal.cx> | 2023-02-28 12:00:55 -0500 |
commit | 595416b11dfbc82d40a59d0edd7e3b04ba7a2d6d (patch) | |
tree | c0c7ecedfe3f6413f851fff003b7282146ae73ae | |
parent | 1a708ece1ad8b924466e81c5fcdf4e22311fd770 (diff) | |
download | musl-595416b11dfbc82d40a59d0edd7e3b04ba7a2d6d.tar.gz musl-595416b11dfbc82d40a59d0edd7e3b04ba7a2d6d.tar.xz musl-595416b11dfbc82d40a59d0edd7e3b04ba7a2d6d.zip |
getservbyport_r: fix out-of-bounds buffer read
If the buffer passed to getservbyport_r is just enough to store two pointers after aligning it, getnameinfo is called with buflen == 0 (which means that service name is not needed) and trivially succeeds. Then, strtol is called on the address just past the buffer end, and if it doesn't happen to find the port number there, getservbyport_r spuriously succeeds and returns the same bad address to the caller. Fix this by ensuring that buflen is at least 1 when passed to getnameinfo.
-rw-r--r-- | src/network/getservbyport_r.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/src/network/getservbyport_r.c b/src/network/getservbyport_r.c index b7f21c6b..d3a22b8c 100644 --- a/src/network/getservbyport_r.c +++ b/src/network/getservbyport_r.c @@ -26,7 +26,7 @@ int getservbyport_r(int port, const char *prots, /* Align buffer */ i = (uintptr_t)buf & sizeof(char *)-1; if (!i) i = sizeof(char *); - if (buflen < 3*sizeof(char *)-i) + if (buflen <= 3*sizeof(char *)-i) return ERANGE; buf += sizeof(char *)-i; buflen -= sizeof(char *)-i; |