From abc5c44d6284fab8fb21bcfc52c0f16f980637df Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 23 Apr 2009 19:31:25 -0400 Subject: SUNRPC: Fix error return value of svc_addr_len() The svc_addr_len() helper function returns -EAFNOSUPPORT if it doesn't recognize the address family of the passed-in socket address. However, the return type of this function is size_t, which means -EAFNOSUPPORT is turned into a very large positive value in this case. The check in svc_udp_recvfrom() to see if the return value is less than zero therefore won't work at all. Additionally, handle_connect_req() passes this value directly to memset(). This could cause memset() to clobber a large chunk of memory if svc_addr_len() has returned an error. Currently the address family of these addresses, however, is known to be supported long before handle_connect_req() is called, so this isn't a real risk. Change the error return value of svc_addr_len() to zero, which fits in the range of size_t, and is safer to pass to memset() directly. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- include/linux/sunrpc/svc_xprt.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/linux/sunrpc') diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h index 0d9cb6ef28b..d790c52525c 100644 --- a/include/linux/sunrpc/svc_xprt.h +++ b/include/linux/sunrpc/svc_xprt.h @@ -118,7 +118,7 @@ static inline unsigned short svc_addr_port(const struct sockaddr *sa) return 0; } -static inline size_t svc_addr_len(struct sockaddr *sa) +static inline size_t svc_addr_len(const struct sockaddr *sa) { switch (sa->sa_family) { case AF_INET: @@ -126,7 +126,8 @@ static inline size_t svc_addr_len(struct sockaddr *sa) case AF_INET6: return sizeof(struct sockaddr_in6); } - return -EAFNOSUPPORT; + + return 0; } static inline unsigned short svc_xprt_local_port(const struct svc_xprt *xprt) -- cgit v1.2.3 From 335c54bdc4d3bacdbd619ec95cd0b352435bd37f Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 23 Apr 2009 19:32:25 -0400 Subject: NFSD: Prevent a buffer overflow in svc_xprt_names() The svc_xprt_names() function can overflow its buffer if it's so near the end of the passed in buffer that the "name too long" string still doesn't fit. Of course, it could never tell if it was near the end of the passed in buffer, since its only caller passes in zero as the buffer length. Let's make this API a little safer. Change svc_xprt_names() so it *always* checks for a buffer overflow, and change its only caller to pass in the correct buffer length. If svc_xprt_names() does overflow its buffer, it now fails with an ENAMETOOLONG errno, instead of trying to write a message at the end of the buffer. I don't like this much, but I can't figure out a clean way that's always safe to return some of the names, *and* an indication that the buffer was not long enough. The displayed error when doing a 'cat /proc/fs/nfsd/portlist' is "File name too long". Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- include/linux/sunrpc/svc_xprt.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/sunrpc') diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h index d790c52525c..2223ae0b5ed 100644 --- a/include/linux/sunrpc/svc_xprt.h +++ b/include/linux/sunrpc/svc_xprt.h @@ -83,7 +83,7 @@ int svc_port_is_privileged(struct sockaddr *sin); int svc_print_xprts(char *buf, int maxlen); struct svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name, const sa_family_t af, const unsigned short port); -int svc_xprt_names(struct svc_serv *serv, char *buf, int buflen); +int svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen); static inline void svc_xprt_get(struct svc_xprt *xprt) { -- cgit v1.2.3 From bfba9ab4c64f0e5c33930711e6c073c285e01fcf Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 23 Apr 2009 19:32:33 -0400 Subject: SUNRPC: pass buffer size to svc_addsock() Adjust the synopsis of svc_addsock() to pass in the size of the output buffer. Add a documenting comment. This is a cosmetic change for now. A subsequent patch will make sure the buffer length is passed to one_sock_name(), where the length will actually be useful. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- include/linux/sunrpc/svcsock.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux/sunrpc') diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h index 483e10380aa..e23241c53f4 100644 --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -39,7 +39,8 @@ int svc_send(struct svc_rqst *); void svc_drop(struct svc_rqst *); void svc_sock_update_bufs(struct svc_serv *serv); int svc_sock_names(char *buf, struct svc_serv *serv, char *toclose); -int svc_addsock(struct svc_serv *serv, int fd, char *name_return); +int svc_addsock(struct svc_serv *serv, const int fd, + char *name_return, const size_t len); void svc_init_xprt_sock(void); void svc_cleanup_xprt_sock(void); -- cgit v1.2.3 From 8435d34dbbe75678c3cdad3d53b1e7996a79b3bf Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 23 Apr 2009 19:32:40 -0400 Subject: SUNRPC: pass buffer size to svc_sock_names() Adjust the synopsis of svc_sock_names() to pass in the size of the output buffer. Add a documenting comment. This is a cosmetic change for now. A subsequent patch will make sure the buffer length is passed to one_sock_name(), where the length will actually be useful. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- include/linux/sunrpc/svcsock.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include/linux/sunrpc') diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h index e23241c53f4..82716313894 100644 --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -38,7 +38,9 @@ int svc_recv(struct svc_rqst *, long); int svc_send(struct svc_rqst *); void svc_drop(struct svc_rqst *); void svc_sock_update_bufs(struct svc_serv *serv); -int svc_sock_names(char *buf, struct svc_serv *serv, char *toclose); +int svc_sock_names(struct svc_serv *serv, char *buf, + const size_t buflen, + const char *toclose); int svc_addsock(struct svc_serv *serv, const int fd, char *name_return, const size_t len); void svc_init_xprt_sock(void); -- cgit v1.2.3