From c6ee11c39fcc1fb55130748990a8f199e76263b4 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 6 Oct 2019 14:24:24 -0700 Subject: [PATCH 1/4] llc: fix sk_buff leak in llc_sap_state_process() syzbot reported: BUG: memory leak unreferenced object 0xffff888116270800 (size 224): comm "syz-executor641", pid 7047, jiffies 4294947360 (age 13.860s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 20 e1 2a 81 88 ff ff 00 40 3d 2a 81 88 ff ff . .*.....@=*.... backtrace: [<000000004d41b4cc>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<000000004d41b4cc>] slab_post_alloc_hook mm/slab.h:439 [inline] [<000000004d41b4cc>] slab_alloc_node mm/slab.c:3269 [inline] [<000000004d41b4cc>] kmem_cache_alloc_node+0x153/0x2a0 mm/slab.c:3579 [<00000000506a5965>] __alloc_skb+0x6e/0x210 net/core/skbuff.c:198 [<000000001ba5a161>] alloc_skb include/linux/skbuff.h:1058 [inline] [<000000001ba5a161>] alloc_skb_with_frags+0x5f/0x250 net/core/skbuff.c:5327 [<0000000047d9c78b>] sock_alloc_send_pskb+0x269/0x2a0 net/core/sock.c:2225 [<000000003828fe54>] sock_alloc_send_skb+0x32/0x40 net/core/sock.c:2242 [<00000000e34d94f9>] llc_ui_sendmsg+0x10a/0x540 net/llc/af_llc.c:933 [<00000000de2de3fb>] sock_sendmsg_nosec net/socket.c:652 [inline] [<00000000de2de3fb>] sock_sendmsg+0x54/0x70 net/socket.c:671 [<000000008fe16e7a>] __sys_sendto+0x148/0x1f0 net/socket.c:1964 [...] The bug is that llc_sap_state_process() always takes an extra reference to the skb, but sometimes neither llc_sap_next_state() nor llc_sap_state_process() itself drops this reference. Fix it by changing llc_sap_next_state() to never consume a reference to the skb, rather than sometimes do so and sometimes not. Then remove the extra skb_get() and kfree_skb() from llc_sap_state_process(). Reported-by: syzbot+6bf095f9becf5efef645@syzkaller.appspotmail.com Reported-by: syzbot+31c16aa4202dace3812e@syzkaller.appspotmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Biggers Signed-off-by: Jakub Kicinski --- net/llc/llc_s_ac.c | 12 +++++++++--- net/llc/llc_sap.c | 23 ++++++++--------------- 2 files changed, 17 insertions(+), 18 deletions(-) diff --git a/net/llc/llc_s_ac.c b/net/llc/llc_s_ac.c index a94bd56bcac6..7ae4cc684d3a 100644 --- a/net/llc/llc_s_ac.c +++ b/net/llc/llc_s_ac.c @@ -58,8 +58,10 @@ int llc_sap_action_send_ui(struct llc_sap *sap, struct sk_buff *skb) ev->daddr.lsap, LLC_PDU_CMD); llc_pdu_init_as_ui_cmd(skb); rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac); - if (likely(!rc)) + if (likely(!rc)) { + skb_get(skb); rc = dev_queue_xmit(skb); + } return rc; } @@ -81,8 +83,10 @@ int llc_sap_action_send_xid_c(struct llc_sap *sap, struct sk_buff *skb) ev->daddr.lsap, LLC_PDU_CMD); llc_pdu_init_as_xid_cmd(skb, LLC_XID_NULL_CLASS_2, 0); rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac); - if (likely(!rc)) + if (likely(!rc)) { + skb_get(skb); rc = dev_queue_xmit(skb); + } return rc; } @@ -135,8 +139,10 @@ int llc_sap_action_send_test_c(struct llc_sap *sap, struct sk_buff *skb) ev->daddr.lsap, LLC_PDU_CMD); llc_pdu_init_as_test_cmd(skb); rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac); - if (likely(!rc)) + if (likely(!rc)) { + skb_get(skb); rc = dev_queue_xmit(skb); + } return rc; } diff --git a/net/llc/llc_sap.c b/net/llc/llc_sap.c index a7f7b8ff4729..be419062e19a 100644 --- a/net/llc/llc_sap.c +++ b/net/llc/llc_sap.c @@ -197,29 +197,22 @@ out: * After executing actions of the event, upper layer will be indicated * if needed(on receiving an UI frame). sk can be null for the * datalink_proto case. + * + * This function always consumes a reference to the skb. */ static void llc_sap_state_process(struct llc_sap *sap, struct sk_buff *skb) { struct llc_sap_state_ev *ev = llc_sap_ev(skb); - /* - * We have to hold the skb, because llc_sap_next_state - * will kfree it in the sending path and we need to - * look at the skb->cb, where we encode llc_sap_state_ev. - */ - skb_get(skb); ev->ind_cfm_flag = 0; llc_sap_next_state(sap, skb); - if (ev->ind_cfm_flag == LLC_IND) { - if (skb->sk->sk_state == TCP_LISTEN) - kfree_skb(skb); - else { - llc_save_primitive(skb->sk, skb, ev->prim); - /* queue skb to the user. */ - if (sock_queue_rcv_skb(skb->sk, skb)) - kfree_skb(skb); - } + if (ev->ind_cfm_flag == LLC_IND && skb->sk->sk_state != TCP_LISTEN) { + llc_save_primitive(skb->sk, skb, ev->prim); + + /* queue skb to the user. */ + if (sock_queue_rcv_skb(skb->sk, skb) == 0) + return; } kfree_skb(skb); } From b74555de21acd791f12c4a1aeaf653dd7ac21133 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 6 Oct 2019 14:24:25 -0700 Subject: [PATCH 2/4] llc: fix sk_buff leak in llc_conn_service() syzbot reported: BUG: memory leak unreferenced object 0xffff88811eb3de00 (size 224): comm "syz-executor559", pid 7315, jiffies 4294943019 (age 10.300s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 a0 38 24 81 88 ff ff 00 c0 f2 15 81 88 ff ff ..8$............ backtrace: [<000000008d1c66a1>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<000000008d1c66a1>] slab_post_alloc_hook mm/slab.h:439 [inline] [<000000008d1c66a1>] slab_alloc_node mm/slab.c:3269 [inline] [<000000008d1c66a1>] kmem_cache_alloc_node+0x153/0x2a0 mm/slab.c:3579 [<00000000447d9496>] __alloc_skb+0x6e/0x210 net/core/skbuff.c:198 [<000000000cdbf82f>] alloc_skb include/linux/skbuff.h:1058 [inline] [<000000000cdbf82f>] llc_alloc_frame+0x66/0x110 net/llc/llc_sap.c:54 [<000000002418b52e>] llc_conn_ac_send_sabme_cmd_p_set_x+0x2f/0x140 net/llc/llc_c_ac.c:777 [<000000001372ae17>] llc_exec_conn_trans_actions net/llc/llc_conn.c:475 [inline] [<000000001372ae17>] llc_conn_service net/llc/llc_conn.c:400 [inline] [<000000001372ae17>] llc_conn_state_process+0x1ac/0x640 net/llc/llc_conn.c:75 [<00000000f27e53c1>] llc_establish_connection+0x110/0x170 net/llc/llc_if.c:109 [<00000000291b2ca0>] llc_ui_connect+0x10e/0x370 net/llc/af_llc.c:477 [<000000000f9c740b>] __sys_connect+0x11d/0x170 net/socket.c:1840 [...] The bug is that most callers of llc_conn_send_pdu() assume it consumes a reference to the skb, when actually due to commit b85ab56c3f81 ("llc: properly handle dev_queue_xmit() return value") it doesn't. Revert most of that commit, and instead make the few places that need llc_conn_send_pdu() to *not* consume a reference call skb_get() before. Fixes: b85ab56c3f81 ("llc: properly handle dev_queue_xmit() return value") Reported-by: syzbot+6b825a6494a04cc0e3f7@syzkaller.appspotmail.com Signed-off-by: Eric Biggers Signed-off-by: Jakub Kicinski --- include/net/llc_conn.h | 2 +- net/llc/llc_c_ac.c | 8 ++++++-- net/llc/llc_conn.c | 32 +++++++++----------------------- 3 files changed, 16 insertions(+), 26 deletions(-) diff --git a/include/net/llc_conn.h b/include/net/llc_conn.h index df528a623548..ea985aa7a6c5 100644 --- a/include/net/llc_conn.h +++ b/include/net/llc_conn.h @@ -104,7 +104,7 @@ void llc_sk_reset(struct sock *sk); /* Access to a connection */ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb); -int llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb); +void llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb); void llc_conn_rtn_pdu(struct sock *sk, struct sk_buff *skb); void llc_conn_resend_i_pdu_as_cmd(struct sock *sk, u8 nr, u8 first_p_bit); void llc_conn_resend_i_pdu_as_rsp(struct sock *sk, u8 nr, u8 first_f_bit); diff --git a/net/llc/llc_c_ac.c b/net/llc/llc_c_ac.c index 4d78375f9872..647c0554d04c 100644 --- a/net/llc/llc_c_ac.c +++ b/net/llc/llc_c_ac.c @@ -372,6 +372,7 @@ int llc_conn_ac_send_i_cmd_p_set_1(struct sock *sk, struct sk_buff *skb) llc_pdu_init_as_i_cmd(skb, 1, llc->vS, llc->vR); rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac); if (likely(!rc)) { + skb_get(skb); llc_conn_send_pdu(sk, skb); llc_conn_ac_inc_vs_by_1(sk, skb); } @@ -389,7 +390,8 @@ static int llc_conn_ac_send_i_cmd_p_set_0(struct sock *sk, struct sk_buff *skb) llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR); rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac); if (likely(!rc)) { - rc = llc_conn_send_pdu(sk, skb); + skb_get(skb); + llc_conn_send_pdu(sk, skb); llc_conn_ac_inc_vs_by_1(sk, skb); } return rc; @@ -406,6 +408,7 @@ int llc_conn_ac_send_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb) llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR); rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac); if (likely(!rc)) { + skb_get(skb); llc_conn_send_pdu(sk, skb); llc_conn_ac_inc_vs_by_1(sk, skb); } @@ -916,7 +919,8 @@ static int llc_conn_ac_send_i_rsp_f_set_ackpf(struct sock *sk, llc_pdu_init_as_i_cmd(skb, llc->ack_pf, llc->vS, llc->vR); rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac); if (likely(!rc)) { - rc = llc_conn_send_pdu(sk, skb); + skb_get(skb); + llc_conn_send_pdu(sk, skb); llc_conn_ac_inc_vs_by_1(sk, skb); } return rc; diff --git a/net/llc/llc_conn.c b/net/llc/llc_conn.c index 4ff89cb7c86f..ed2aca12460c 100644 --- a/net/llc/llc_conn.c +++ b/net/llc/llc_conn.c @@ -30,7 +30,7 @@ #endif static int llc_find_offset(int state, int ev_type); -static int llc_conn_send_pdus(struct sock *sk, struct sk_buff *skb); +static void llc_conn_send_pdus(struct sock *sk); static int llc_conn_service(struct sock *sk, struct sk_buff *skb); static int llc_exec_conn_trans_actions(struct sock *sk, struct llc_conn_state_trans *trans, @@ -193,11 +193,11 @@ out_skb_put: return rc; } -int llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb) +void llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb) { /* queue PDU to send to MAC layer */ skb_queue_tail(&sk->sk_write_queue, skb); - return llc_conn_send_pdus(sk, skb); + llc_conn_send_pdus(sk); } /** @@ -255,7 +255,7 @@ void llc_conn_resend_i_pdu_as_cmd(struct sock *sk, u8 nr, u8 first_p_bit) if (howmany_resend > 0) llc->vS = (llc->vS + 1) % LLC_2_SEQ_NBR_MODULO; /* any PDUs to re-send are queued up; start sending to MAC */ - llc_conn_send_pdus(sk, NULL); + llc_conn_send_pdus(sk); out:; } @@ -296,7 +296,7 @@ void llc_conn_resend_i_pdu_as_rsp(struct sock *sk, u8 nr, u8 first_f_bit) if (howmany_resend > 0) llc->vS = (llc->vS + 1) % LLC_2_SEQ_NBR_MODULO; /* any PDUs to re-send are queued up; start sending to MAC */ - llc_conn_send_pdus(sk, NULL); + llc_conn_send_pdus(sk); out:; } @@ -340,16 +340,12 @@ out: /** * llc_conn_send_pdus - Sends queued PDUs * @sk: active connection - * @hold_skb: the skb held by caller, or NULL if does not care * - * Sends queued pdus to MAC layer for transmission. When @hold_skb is - * NULL, always return 0. Otherwise, return 0 if @hold_skb is sent - * successfully, or 1 for failure. + * Sends queued pdus to MAC layer for transmission. */ -static int llc_conn_send_pdus(struct sock *sk, struct sk_buff *hold_skb) +static void llc_conn_send_pdus(struct sock *sk) { struct sk_buff *skb; - int ret = 0; while ((skb = skb_dequeue(&sk->sk_write_queue)) != NULL) { struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb); @@ -361,20 +357,10 @@ static int llc_conn_send_pdus(struct sock *sk, struct sk_buff *hold_skb) skb_queue_tail(&llc_sk(sk)->pdu_unack_q, skb); if (!skb2) break; - dev_queue_xmit(skb2); - } else { - bool is_target = skb == hold_skb; - int rc; - - if (is_target) - skb_get(skb); - rc = dev_queue_xmit(skb); - if (is_target) - ret = rc; + skb = skb2; } + dev_queue_xmit(skb); } - - return ret; } /** From fc8d5db10cbe1338a52ebc74e7feab9276721774 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 6 Oct 2019 14:24:26 -0700 Subject: [PATCH 3/4] llc: fix another potential sk_buff leak in llc_ui_sendmsg() All callers of llc_conn_state_process() except llc_build_and_send_pkt() (via llc_ui_sendmsg() -> llc_ui_send_data()) assume that it always consumes a reference to the skb. Fix this caller to do the same. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Biggers Signed-off-by: Jakub Kicinski --- net/llc/af_llc.c | 34 ++++++++++++++++++++-------------- net/llc/llc_conn.c | 2 ++ net/llc/llc_if.c | 12 ++++++++---- 3 files changed, 30 insertions(+), 18 deletions(-) diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c index 2017b7d780f5..c74f44dfaa22 100644 --- a/net/llc/af_llc.c +++ b/net/llc/af_llc.c @@ -113,22 +113,26 @@ static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr) * * Send data via reliable llc2 connection. * Returns 0 upon success, non-zero if action did not succeed. + * + * This function always consumes a reference to the skb. */ static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock) { struct llc_sock* llc = llc_sk(sk); - int rc = 0; if (unlikely(llc_data_accept_state(llc->state) || llc->remote_busy_flag || llc->p_flag)) { long timeout = sock_sndtimeo(sk, noblock); + int rc; rc = llc_ui_wait_for_busy_core(sk, timeout); + if (rc) { + kfree_skb(skb); + return rc; + } } - if (unlikely(!rc)) - rc = llc_build_and_send_pkt(sk, skb); - return rc; + return llc_build_and_send_pkt(sk, skb); } static void llc_ui_sk_init(struct socket *sock, struct sock *sk) @@ -899,7 +903,7 @@ static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) DECLARE_SOCKADDR(struct sockaddr_llc *, addr, msg->msg_name); int flags = msg->msg_flags; int noblock = flags & MSG_DONTWAIT; - struct sk_buff *skb; + struct sk_buff *skb = NULL; size_t size = 0; int rc = -EINVAL, copied = 0, hdrlen; @@ -908,10 +912,10 @@ static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) lock_sock(sk); if (addr) { if (msg->msg_namelen < sizeof(*addr)) - goto release; + goto out; } else { if (llc_ui_addr_null(&llc->addr)) - goto release; + goto out; addr = &llc->addr; } /* must bind connection to sap if user hasn't done it. */ @@ -919,7 +923,7 @@ static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) /* bind to sap with null dev, exclusive. */ rc = llc_ui_autobind(sock, addr); if (rc) - goto release; + goto out; } hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr); size = hdrlen + len; @@ -928,12 +932,12 @@ static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) copied = size - hdrlen; rc = -EINVAL; if (copied < 0) - goto release; + goto out; release_sock(sk); skb = sock_alloc_send_skb(sk, size, noblock, &rc); lock_sock(sk); if (!skb) - goto release; + goto out; skb->dev = llc->dev; skb->protocol = llc_proto_type(addr->sllc_arphrd); skb_reserve(skb, hdrlen); @@ -943,29 +947,31 @@ static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) { llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac, addr->sllc_sap); + skb = NULL; goto out; } if (addr->sllc_test) { llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac, addr->sllc_sap); + skb = NULL; goto out; } if (addr->sllc_xid) { llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac, addr->sllc_sap); + skb = NULL; goto out; } rc = -ENOPROTOOPT; if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua)) goto out; rc = llc_ui_send_data(sk, skb, noblock); + skb = NULL; out: - if (rc) { - kfree_skb(skb); -release: + kfree_skb(skb); + if (rc) dprintk("%s: failed sending from %02X to %02X: %d\n", __func__, llc->laddr.lsap, llc->daddr.lsap, rc); - } release_sock(sk); return rc ? : copied; } diff --git a/net/llc/llc_conn.c b/net/llc/llc_conn.c index ed2aca12460c..0b0c6f12153b 100644 --- a/net/llc/llc_conn.c +++ b/net/llc/llc_conn.c @@ -55,6 +55,8 @@ int sysctl_llc2_busy_timeout = LLC2_BUSY_TIME * HZ; * (executing it's actions and changing state), upper layer will be * indicated or confirmed, if needed. Returns 0 for success, 1 for * failure. The socket lock has to be held before calling this function. + * + * This function always consumes a reference to the skb. */ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb) { diff --git a/net/llc/llc_if.c b/net/llc/llc_if.c index 8db03c2d5440..ad6547736c21 100644 --- a/net/llc/llc_if.c +++ b/net/llc/llc_if.c @@ -38,6 +38,8 @@ * closed and -EBUSY when sending data is not permitted in this state or * LLC has send an I pdu with p bit set to 1 and is waiting for it's * response. + * + * This function always consumes a reference to the skb. */ int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb) { @@ -46,20 +48,22 @@ int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb) struct llc_sock *llc = llc_sk(sk); if (unlikely(llc->state == LLC_CONN_STATE_ADM)) - goto out; + goto out_free; rc = -EBUSY; if (unlikely(llc_data_accept_state(llc->state) || /* data_conn_refuse */ llc->p_flag)) { llc->failed_data_req = 1; - goto out; + goto out_free; } ev = llc_conn_ev(skb); ev->type = LLC_CONN_EV_TYPE_PRIM; ev->prim = LLC_DATA_PRIM; ev->prim_type = LLC_PRIM_TYPE_REQ; skb->dev = llc->dev; - rc = llc_conn_state_process(sk, skb); -out: + return llc_conn_state_process(sk, skb); + +out_free: + kfree_skb(skb); return rc; } From 36453c852816f19947ca482a595dffdd2efa4965 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 6 Oct 2019 14:24:27 -0700 Subject: [PATCH 4/4] llc: fix sk_buff refcounting in llc_conn_state_process() If llc_conn_state_process() sees that llc_conn_service() put the skb on a list, it will drop one fewer references to it. This is wrong because the current behavior is that llc_conn_service() never consumes a reference to the skb. The code also makes the number of skb references being dropped conditional on which of ind_prim and cfm_prim are nonzero, yet neither of these affects how many references are *acquired*. So there is extra code that tries to fix this up by sometimes taking another reference. Remove the unnecessary/broken refcounting logic and instead just add an skb_get() before the only two places where an extra reference is actually consumed. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Biggers Signed-off-by: Jakub Kicinski --- net/llc/llc_conn.c | 33 ++++++--------------------------- 1 file changed, 6 insertions(+), 27 deletions(-) diff --git a/net/llc/llc_conn.c b/net/llc/llc_conn.c index 0b0c6f12153b..a79b739eb223 100644 --- a/net/llc/llc_conn.c +++ b/net/llc/llc_conn.c @@ -64,12 +64,6 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb) struct llc_sock *llc = llc_sk(skb->sk); struct llc_conn_state_ev *ev = llc_conn_ev(skb); - /* - * We have to hold the skb, because llc_conn_service will kfree it in - * the sending path and we need to look at the skb->cb, where we encode - * llc_conn_state_ev. - */ - skb_get(skb); ev->ind_prim = ev->cfm_prim = 0; /* * Send event to state machine @@ -77,21 +71,12 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb) rc = llc_conn_service(skb->sk, skb); if (unlikely(rc != 0)) { printk(KERN_ERR "%s: llc_conn_service failed\n", __func__); - goto out_kfree_skb; - } - - if (unlikely(!ev->ind_prim && !ev->cfm_prim)) { - /* indicate or confirm not required */ - if (!skb->next) - goto out_kfree_skb; goto out_skb_put; } - if (unlikely(ev->ind_prim && ev->cfm_prim)) /* Paranoia */ - skb_get(skb); - switch (ev->ind_prim) { case LLC_DATA_PRIM: + skb_get(skb); llc_save_primitive(sk, skb, LLC_DATA_PRIM); if (unlikely(sock_queue_rcv_skb(sk, skb))) { /* @@ -108,6 +93,7 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb) * skb->sk pointing to the newly created struct sock in * llc_conn_handler. -acme */ + skb_get(skb); skb_queue_tail(&sk->sk_receive_queue, skb); sk->sk_state_change(sk); break; @@ -123,7 +109,6 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb) sk->sk_state_change(sk); } } - kfree_skb(skb); sock_put(sk); break; case LLC_RESET_PRIM: @@ -132,14 +117,11 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb) * RESET is not being notified to upper layers for now */ printk(KERN_INFO "%s: received a reset ind!\n", __func__); - kfree_skb(skb); break; default: - if (ev->ind_prim) { + if (ev->ind_prim) printk(KERN_INFO "%s: received unknown %d prim!\n", __func__, ev->ind_prim); - kfree_skb(skb); - } /* No indication */ break; } @@ -181,15 +163,12 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb) printk(KERN_INFO "%s: received a reset conf!\n", __func__); break; default: - if (ev->cfm_prim) { + if (ev->cfm_prim) printk(KERN_INFO "%s: received unknown %d prim!\n", __func__, ev->cfm_prim); - break; - } - goto out_skb_put; /* No confirmation */ + /* No confirmation */ + break; } -out_kfree_skb: - kfree_skb(skb); out_skb_put: kfree_skb(skb); return rc;