diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2016-03-29 11:54:58 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2016-03-29 11:54:58 -0400 |
| commit | b4b06931ed22e9a38442b16676aaf16ace92bf8d (patch) | |
| tree | 15f3c76110098c24fc26f51dbc61d1fe694ad8f7 /src/backend/libpq/auth.c | |
| parent | 4edcd5f5d23c55f60d6c11451437437611731fff (diff) | |
Avoid possibly-unsafe use of Windows' FormatMessage() function.
Whenever this function is used with the FORMAT_MESSAGE_FROM_SYSTEM flag,
it's good practice to include FORMAT_MESSAGE_IGNORE_INSERTS as well.
Otherwise, if the message contains any %n insertion markers, the function
will try to fetch argument strings to substitute --- which we are not
passing, possibly leading to a crash. This is exactly analogous to the
rule about not giving printf() a format string you're not in control of.
Noted and patched by Christian Ullrich.
Back-patch to all supported branches.
Diffstat (limited to 'src/backend/libpq/auth.c')
| -rw-r--r-- | src/backend/libpq/auth.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c index bc3bd5f3278..51d167fdfc0 100644 --- a/src/backend/libpq/auth.c +++ b/src/backend/libpq/auth.c @@ -1222,7 +1222,9 @@ pg_SSPI_error(int severity, const char *errmsg, SECURITY_STATUS r) { char sysmsg[256]; - if (FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, r, 0, + if (FormatMessage(FORMAT_MESSAGE_IGNORE_INSERTS | + FORMAT_MESSAGE_FROM_SYSTEM, + NULL, r, 0, sysmsg, sizeof(sysmsg), NULL) == 0) ereport(severity, (errmsg_internal("%s", errmsg), |