mountd: fix --manage-gids hang due to int/uint bug

A uid or gid should be represented as unsigned, not signed.

The conversion to signed here could cause a hang on access by an unknown
user to a server running mountd with --manage-gids; such a user is
likely to be mapped to 232-1, which may be converted to 231-1 when
represented as an int, resulting in a downcall for uid 231-1, hence the
original rpc hanging forever waiting for a cache downcall for 232-1.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Steve Dickson <steved@redhat.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/support/nfs/cacheio.c b/support/nfs/cacheio.c
index bdf5d84..0587ecb 100644
--- a/support/nfs/cacheio.c
+++ b/support/nfs/cacheio.c
@@ -148,6 +148,11 @@ void qword_printint(FILE *f, int num)
 	fprintf(f, "%d ", num);
 }
 
+void qword_printuint(FILE *f, unsigned int num)
+{
+	fprintf(f, "%u ", num);
+}
+
 int qword_eol(FILE *f)
 {
 	int err;
@@ -236,6 +241,20 @@ int qword_get_int(char **bpp, int *anint)
 	return 0;
 }
 
+int qword_get_uint(char *bpp, unsigned int *anint)
+{
+	char buf[50];
+	char *ep;
+	unsigned int rv;
+	int len = qword_get(bpp, buf, 50);
+	if (len < 0) return -1;
+	if (len ==0) return -1;
+	rv = strtoul(buf, &ep, 0);
+	if (*ep) return -1;
+	*anint = rv;
+	return 0;
+}
+
 #define READLINE_BUFFER_INCREMENT 2048
 
 int readline(int fd, char **buf, int *lenp)