5.4-stable review patch. If anyone has any objections, please let me know.
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From: Pablo Neira Ayuso pablo@netfilter.org
[ Upstream commit 7515e37bce5c428a56a9b04ea7e96b3f53f17150 ]
Existing user space applications maintained by the Osmocom project are breaking since a recent fix that addresses incorrect error checking.
Restore operation for user space programs that specify -1 as file descriptor to skip GTPv0 or GTPv1 only sockets.
Fixes: defd8b3c37b0 ("gtp: fix a potential NULL pointer dereference") Reported-by: Pau Espin Pedrol pespin@sysmocom.de Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Tested-by: Oliver Smith osmith@sysmocom.de Reviewed-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/20241022144825.66740-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/gtp.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c index 9c62bc277ae86..f85f4e3d28215 100644 --- a/drivers/net/gtp.c +++ b/drivers/net/gtp.c @@ -848,20 +848,24 @@ static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]) unsigned int role = GTP_ROLE_GGSN;
if (data[IFLA_GTP_FD0]) { - u32 fd0 = nla_get_u32(data[IFLA_GTP_FD0]); + int fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
- sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp); - if (IS_ERR(sk0)) - return PTR_ERR(sk0); + if (fd0 >= 0) { + sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp); + if (IS_ERR(sk0)) + return PTR_ERR(sk0); + } }
if (data[IFLA_GTP_FD1]) { - u32 fd1 = nla_get_u32(data[IFLA_GTP_FD1]); + int fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
- sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp); - if (IS_ERR(sk1u)) { - gtp_encap_disable_sock(sk0); - return PTR_ERR(sk1u); + if (fd1 >= 0) { + sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp); + if (IS_ERR(sk1u)) { + gtp_encap_disable_sock(sk0); + return PTR_ERR(sk1u); + } } }