From: David Howells dhowells@redhat.com
[ Upstream commit 020c69c1a793ed29d28793808eddd75210c858dd ]
UTS_RELEASE has a maximum length of 64 which can cause rxrpc_version to exceed the 65 byte message limit.
Per the rx spec[1]: "If a server receives a packet with a type value of 13, and the client-initiated flag set, it should respond with a 65-byte payload containing a string that identifies the version of AFS software it is running."
The current implementation causes a compile error when WERROR is turned on and/or UTS_RELEASE exceeds the length of 49 (making the version string more than 64 characters).
Fix this by generating the string during module initialisation and limiting the UTS_RELEASE segment of the string does not exceed 49 chars. We need to make sure that the 64 bytes includes "linux-" at the front and " AF_RXRPC" at the back as this may be used in pattern matching.
Fixes: 44ba06987c0b ("RxRPC: Handle VERSION Rx protocol packets") Reported-by: Kenny Ho Kenny.Ho@amd.com Link: https://lore.kernel.org/r/20230523223944.691076-1-Kenny.Ho@amd.com/ Signed-off-by: David Howells dhowells@redhat.com Acked-by: Kenny Ho Kenny.Ho@amd.com cc: Marc Dionne marc.dionne@auristor.com cc: Andrew Lunn andrew@lunn.ch cc: David Laight David.Laight@ACULAB.COM cc: "David S. Miller" davem@davemloft.net cc: Eric Dumazet edumazet@google.com cc: Jakub Kicinski kuba@kernel.org cc: Paolo Abeni pabeni@redhat.com cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org Link: https://web.mit.edu/kolya/afs/rx/rx-spec [1] Reviewed-by: Simon Horman simon.horman@corigine.com Reviewed-by: Jeffrey Altman jaltman@auristor.com Link: https://lore.kernel.org/r/654974.1685100894@warthog.procyon.org.uk Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/rxrpc/af_rxrpc.c | 1 + net/rxrpc/ar-internal.h | 1 + net/rxrpc/local_event.c | 11 ++++++++++- 3 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c index a6f0d29f35ef9..f5d1fc1266a5a 100644 --- a/net/rxrpc/af_rxrpc.c +++ b/net/rxrpc/af_rxrpc.c @@ -967,6 +967,7 @@ static int __init af_rxrpc_init(void) BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof_field(struct sk_buff, cb));
ret = -ENOMEM; + rxrpc_gen_version_string(); rxrpc_call_jar = kmem_cache_create( "rxrpc_call_jar", sizeof(struct rxrpc_call), 0, SLAB_HWCACHE_ALIGN, NULL); diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index 5d44dc08f66d0..e8e14c6f904d9 100644 --- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -1068,6 +1068,7 @@ int rxrpc_get_server_data_key(struct rxrpc_connection *, const void *, time64_t, /* * local_event.c */ +void rxrpc_gen_version_string(void); void rxrpc_send_version_request(struct rxrpc_local *local, struct rxrpc_host_header *hdr, struct sk_buff *skb); diff --git a/net/rxrpc/local_event.c b/net/rxrpc/local_event.c index 5e69ea6b233da..993c69f97488c 100644 --- a/net/rxrpc/local_event.c +++ b/net/rxrpc/local_event.c @@ -16,7 +16,16 @@ #include <generated/utsrelease.h> #include "ar-internal.h"
-static const char rxrpc_version_string[65] = "linux-" UTS_RELEASE " AF_RXRPC"; +static char rxrpc_version_string[65]; // "linux-" UTS_RELEASE " AF_RXRPC"; + +/* + * Generate the VERSION packet string. + */ +void rxrpc_gen_version_string(void) +{ + snprintf(rxrpc_version_string, sizeof(rxrpc_version_string), + "linux-%.49s AF_RXRPC", UTS_RELEASE); +}
/* * Reply to a version request