From 0a4b34031279d938c2e59df8df7159d6c11e39b5 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Mon, 2 Nov 2020 21:11:50 -0500 Subject: [PATCH] Fix unportable use of getnameinfo() in pg_hba_file_rules view. fill_hba_line() thought it could get away with passing sizeof(struct sockaddr_storage) rather than the actual addrlen previously returned by getaddrinfo(). While that appears to work on many platforms, it does not work on FreeBSD 11: you get back a failure, which leads to the view showing NULL for the address and netmask columns in all rows. The POSIX spec for getnameinfo() is pretty clearly on FreeBSD's side here: you should pass the actual address length. So it seems plausible that there are other platforms where this coding also fails, and we just hadn't noticed. Also, IMO the fact that getnameinfo() failure leads to a NULL output is pretty bogus in itself. Our pg_getnameinfo_all() wrapper is careful to emit "???" on failure, and we should use that in such cases. NULL should only be emitted in rows that don't have IP addresses. Per bug #16695 from Peter Vandivier. Back-patch to v10 where this code was added. Discussion: https://postgr.es/m/16695-a665558e2f630be7@postgresql.org --- src/backend/libpq/hba.c | 31 +++++++++++++++++++++---------- src/include/libpq/hba.h | 7 ++++++- 2 files changed, 27 insertions(+), 11 deletions(-) diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c index 4c86fb6087..3a78d2043e 100644 --- a/src/backend/libpq/hba.c +++ b/src/backend/libpq/hba.c @@ -1188,8 +1188,11 @@ parse_hba_line(TokenizedLine *tok_line, int elevel) ret = pg_getaddrinfo_all(str, NULL, &hints, &gai_result); if (ret == 0 && gai_result) + { memcpy(&parsedline->addr, gai_result->ai_addr, gai_result->ai_addrlen); + parsedline->addrlen = gai_result->ai_addrlen; + } else if (ret == EAI_NONAME) parsedline->hostname = str; else @@ -1238,6 +1241,7 @@ parse_hba_line(TokenizedLine *tok_line, int elevel) token->string); return NULL; } + parsedline->masklen = parsedline->addrlen; pfree(str); } else if (!parsedline->hostname) @@ -1288,6 +1292,7 @@ parse_hba_line(TokenizedLine *tok_line, int elevel) memcpy(&parsedline->mask, gai_result->ai_addr, gai_result->ai_addrlen); + parsedline->masklen = gai_result->ai_addrlen; pg_freeaddrinfo_all(hints.ai_family, gai_result); if (parsedline->addr.ss_family != parsedline->mask.ss_family) @@ -2538,20 +2543,26 @@ fill_hba_line(Tuplestorestate *tuple_store, TupleDesc tupdesc, } else { - if (pg_getnameinfo_all(&hba->addr, sizeof(hba->addr), - buffer, sizeof(buffer), - NULL, 0, - NI_NUMERICHOST) == 0) + /* + * Note: if pg_getnameinfo_all fails, it'll set buffer to + * "???", which we want to return. + */ + if (hba->addrlen > 0) { - clean_ipv6_addr(hba->addr.ss_family, buffer); + if (pg_getnameinfo_all(&hba->addr, hba->addrlen, + buffer, sizeof(buffer), + NULL, 0, + NI_NUMERICHOST) == 0) + clean_ipv6_addr(hba->addr.ss_family, buffer); addrstr = pstrdup(buffer); } - if (pg_getnameinfo_all(&hba->mask, sizeof(hba->mask), - buffer, sizeof(buffer), - NULL, 0, - NI_NUMERICHOST) == 0) + if (hba->masklen > 0) { - clean_ipv6_addr(hba->mask.ss_family, buffer); + if (pg_getnameinfo_all(&hba->mask, hba->masklen, + buffer, sizeof(buffer), + NULL, 0, + NI_NUMERICHOST) == 0) + clean_ipv6_addr(hba->mask.ss_family, buffer); maskstr = pstrdup(buffer); } } diff --git a/src/include/libpq/hba.h b/src/include/libpq/hba.h index d638479d88..8f09b5638f 100644 --- a/src/include/libpq/hba.h +++ b/src/include/libpq/hba.h @@ -42,6 +42,10 @@ typedef enum UserAuth #define USER_AUTH_LAST uaPeer /* Must be last value of this enum */ } UserAuth; +/* + * Data structures representing pg_hba.conf entries + */ + typedef enum IPCompareMethod { ipCmpMask, @@ -75,11 +79,12 @@ typedef struct HbaLine List *databases; List *roles; struct sockaddr_storage addr; + int addrlen; /* zero if we don't have a valid addr */ struct sockaddr_storage mask; + int masklen; /* zero if we don't have a valid mask */ IPCompareMethod ip_cmp_method; char *hostname; UserAuth auth_method; - char *usermap; char *pamservice; bool pam_use_hostname;