From 5a03bc73abed6ae196c15e9950afde19d48be12c Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 10 Apr 2019 11:04:30 -0700 Subject: [PATCH 1/3] net/tls: fix the IV leaks Commit f66de3ee2c16 ("net/tls: Split conf to rx + tx") made freeing of IV and record sequence number conditional to SW path only, but commit e8f69799810c ("net/tls: Add generic NIC offload infrastructure") also allocates that state for the device offload configuration. Remember to free it. Fixes: e8f69799810c ("net/tls: Add generic NIC offload infrastructure") Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- net/tls/tls_device.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c index 135a7ee9db03..38b3b2a9835a 100644 --- a/net/tls/tls_device.c +++ b/net/tls/tls_device.c @@ -52,8 +52,11 @@ static DEFINE_SPINLOCK(tls_device_lock); static void tls_device_free_ctx(struct tls_context *ctx) { - if (ctx->tx_conf == TLS_HW) + if (ctx->tx_conf == TLS_HW) { kfree(tls_offload_ctx_tx(ctx)); + kfree(ctx->tx.rec_seq); + kfree(ctx->tx.iv); + } if (ctx->rx_conf == TLS_HW) kfree(tls_offload_ctx_rx(ctx)); From 35b71a34ada62c9573847a324bf06a133fe11b11 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 10 Apr 2019 11:04:31 -0700 Subject: [PATCH 2/3] net/tls: don't leak partially sent record in device mode David reports that tls triggers warnings related to sk->sk_forward_alloc not being zero at destruction time: WARNING: CPU: 5 PID: 6831 at net/core/stream.c:206 sk_stream_kill_queues+0x103/0x110 WARNING: CPU: 5 PID: 6831 at net/ipv4/af_inet.c:160 inet_sock_destruct+0x15b/0x170 When sender fills up the write buffer and dies from SIGPIPE. This is due to the device implementation not cleaning up the partially_sent_record. This is because commit a42055e8d2c3 ("net/tls: Add support for async encryption of records for performance") moved the partial record cleanup to the SW-only path. Fixes: a42055e8d2c3 ("net/tls: Add support for async encryption of records for performance") Reported-by: David Beckett Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- include/net/tls.h | 2 ++ net/tls/tls_device.c | 7 +++++++ net/tls/tls_main.c | 22 ++++++++++++++++++++++ net/tls/tls_sw.c | 15 +-------------- 4 files changed, 32 insertions(+), 14 deletions(-) diff --git a/include/net/tls.h b/include/net/tls.h index a5a938583295..c7f7dc344e73 100644 --- a/include/net/tls.h +++ b/include/net/tls.h @@ -307,6 +307,7 @@ int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); int tls_device_sendpage(struct sock *sk, struct page *page, int offset, size_t size, int flags); void tls_device_sk_destruct(struct sock *sk); +void tls_device_free_resources_tx(struct sock *sk); void tls_device_init(void); void tls_device_cleanup(void); int tls_tx_records(struct sock *sk, int flags); @@ -330,6 +331,7 @@ int tls_push_sg(struct sock *sk, struct tls_context *ctx, int flags); int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, int flags); +bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx); static inline struct tls_msg *tls_msg(struct sk_buff *skb) { diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c index 38b3b2a9835a..9f3bdbc1e593 100644 --- a/net/tls/tls_device.c +++ b/net/tls/tls_device.c @@ -219,6 +219,13 @@ void tls_device_sk_destruct(struct sock *sk) } EXPORT_SYMBOL(tls_device_sk_destruct); +void tls_device_free_resources_tx(struct sock *sk) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + + tls_free_partial_record(sk, tls_ctx); +} + static void tls_append_frag(struct tls_record_info *record, struct page_frag *pfrag, int size) diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c index df921a2904b9..a3cca1ef0098 100644 --- a/net/tls/tls_main.c +++ b/net/tls/tls_main.c @@ -208,6 +208,26 @@ int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, return tls_push_sg(sk, ctx, sg, offset, flags); } +bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx) +{ + struct scatterlist *sg; + + sg = ctx->partially_sent_record; + if (!sg) + return false; + + while (1) { + put_page(sg_page(sg)); + sk_mem_uncharge(sk, sg->length); + + if (sg_is_last(sg)) + break; + sg++; + } + ctx->partially_sent_record = NULL; + return true; +} + static void tls_write_space(struct sock *sk) { struct tls_context *ctx = tls_get_ctx(sk); @@ -267,6 +287,8 @@ static void tls_sk_proto_close(struct sock *sk, long timeout) kfree(ctx->tx.rec_seq); kfree(ctx->tx.iv); tls_sw_free_resources_tx(sk); + } else if (ctx->tx_conf == TLS_HW) { + tls_device_free_resources_tx(sk); } if (ctx->rx_conf == TLS_SW) { diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 20b191227969..b50ced862f6f 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -2052,20 +2052,7 @@ void tls_sw_free_resources_tx(struct sock *sk) /* Free up un-sent records in tx_list. First, free * the partially sent record if any at head of tx_list. */ - if (tls_ctx->partially_sent_record) { - struct scatterlist *sg = tls_ctx->partially_sent_record; - - while (1) { - put_page(sg_page(sg)); - sk_mem_uncharge(sk, sg->length); - - if (sg_is_last(sg)) - break; - sg++; - } - - tls_ctx->partially_sent_record = NULL; - + if (tls_free_partial_record(sk, tls_ctx)) { rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); list_del(&rec->list); From 4a9c2e3746e6151fd5d077259d79ce9ca86d47d7 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 10 Apr 2019 11:04:32 -0700 Subject: [PATCH 3/3] net: strparser: partially revert "strparser: Call skb_unclone conditionally" This reverts the first part of commit 4e485d06bb8c ("strparser: Call skb_unclone conditionally"). To build a message with multiple fragments we need our own root of frag_list. We can't simply use the frag_list of orig_skb, because it will lead to linking all orig_skbs together creating very long frag chains, and causing stack overflow on kfree_skb() (which is called recursively on the frag_lists). BUG: stack guard page was hit at 00000000d40fad41 (stack is 0000000029dde9f4..000000008cce03d5) kernel stack overflow (double-fault): 0000 [#1] PREEMPT SMP RIP: 0010:free_one_page+0x2b/0x490 Call Trace: __free_pages_ok+0x143/0x2c0 skb_release_data+0x8e/0x140 ? skb_release_data+0xad/0x140 kfree_skb+0x32/0xb0 [...] skb_release_data+0xad/0x140 ? skb_release_data+0xad/0x140 kfree_skb+0x32/0xb0 skb_release_data+0xad/0x140 ? skb_release_data+0xad/0x140 kfree_skb+0x32/0xb0 skb_release_data+0xad/0x140 ? skb_release_data+0xad/0x140 kfree_skb+0x32/0xb0 skb_release_data+0xad/0x140 ? skb_release_data+0xad/0x140 kfree_skb+0x32/0xb0 skb_release_data+0xad/0x140 __kfree_skb+0xe/0x20 tcp_disconnect+0xd6/0x4d0 tcp_close+0xf4/0x430 ? tcp_check_oom+0xf0/0xf0 tls_sk_proto_close+0xe4/0x1e0 [tls] inet_release+0x36/0x60 __sock_release+0x37/0xa0 sock_close+0x11/0x20 __fput+0xa2/0x1d0 task_work_run+0x89/0xb0 exit_to_usermode_loop+0x9a/0xa0 do_syscall_64+0xc0/0xf0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Let's leave the second unclone conditional, as I'm not entirely sure what is its purpose :) Fixes: 4e485d06bb8c ("strparser: Call skb_unclone conditionally") Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller --- net/strparser/strparser.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/net/strparser/strparser.c b/net/strparser/strparser.c index 860dcfb95ee4..fa6c977b4c41 100644 --- a/net/strparser/strparser.c +++ b/net/strparser/strparser.c @@ -140,13 +140,11 @@ static int __strp_recv(read_descriptor_t *desc, struct sk_buff *orig_skb, /* We are going to append to the frags_list of head. * Need to unshare the frag_list. */ - if (skb_has_frag_list(head)) { - err = skb_unclone(head, GFP_ATOMIC); - if (err) { - STRP_STATS_INCR(strp->stats.mem_fail); - desc->error = err; - return 0; - } + err = skb_unclone(head, GFP_ATOMIC); + if (err) { + STRP_STATS_INCR(strp->stats.mem_fail); + desc->error = err; + return 0; } if (unlikely(skb_shinfo(head)->frag_list)) {