Subject: Re: memory leak in create_ctx

From: syzbot <[email-masked]>
Date: Sun, 30 Jun 2019 22:40:00 -0700

Hello,

syzbot has tested the proposed patch but the reproducer still triggered  
crash:
memory leak in create_ctx

2019/07/01 05:38:26 executed programs: 23
BUG: memory leak
unreferenced object 0xffff888102914e00 (size 512):
   comm "syz-executor.4", pid 7333, jiffies 4294944085 (age 13.950s)
   hex dump (first 32 bytes):
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
   backtrace:
     [<000000002f2bb8be>] kmemleak_alloc_recursive  
include/linux/kmemleak.h:55 [inline]
     [<000000002f2bb8be>] slab_post_alloc_hook mm/slab.h:439 [inline]
     [<000000002f2bb8be>] slab_alloc mm/slab.c:3326 [inline]
     [<000000002f2bb8be>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553
     [<00000000b76aef16>] kmalloc include/linux/slab.h:547 [inline]
     [<00000000b76aef16>] kzalloc include/linux/slab.h:742 [inline]
     [<00000000b76aef16>] create_ctx+0x25/0x70 net/tls/tls_main.c:648
     [<00000000dc9c9d2e>] tls_init net/tls/tls_main.c:837 [inline]
     [<00000000dc9c9d2e>] tls_init+0x97/0x1f0 net/tls/tls_main.c:819
     [<000000009d663c39>] __tcp_set_ulp net/ipv4/tcp_ulp.c:126 [inline]
     [<000000009d663c39>] tcp_set_ulp+0xe2/0x190 net/ipv4/tcp_ulp.c:147
     [<00000000551f7621>] do_tcp_setsockopt.isra.0+0x19a/0xd60  
net/ipv4/tcp.c:2789
     [<00000000d02c41d7>] tcp_setsockopt+0x71/0x80 net/ipv4/tcp.c:3103
     [<0000000085d221c1>] sock_common_setsockopt+0x38/0x50  
net/core/sock.c:3129
     [<00000000d294eeda>] __sys_setsockopt+0x98/0x120 net/socket.c:2072
     [<00000000f1f1d607>] __do_sys_setsockopt net/socket.c:2083 [inline]
     [<00000000f1f1d607>] __se_sys_setsockopt net/socket.c:2080 [inline]
     [<00000000f1f1d607>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2080
     [<00000000fbd4f794>] do_syscall_64+0x76/0x1a0  
arch/x86/entry/common.c:301
     [<000000007383b736>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: memory leak
unreferenced object 0xffff888103860c00 (size 512):
   comm "syz-executor.0", pid 7342, jiffies 4294944115 (age 13.650s)
   hex dump (first 32 bytes):
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
   backtrace:
     [<000000002f2bb8be>] kmemleak_alloc_recursive  
include/linux/kmemleak.h:55 [inline]
     [<000000002f2bb8be>] slab_post_alloc_hook mm/slab.h:439 [inline]
     [<000000002f2bb8be>] slab_alloc mm/slab.c:3326 [inline]
     [<000000002f2bb8be>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553
     [<00000000b76aef16>] kmalloc include/linux/slab.h:547 [inline]
     [<00000000b76aef16>] kzalloc include/linux/slab.h:742 [inline]
     [<00000000b76aef16>] create_ctx+0x25/0x70 net/tls/tls_main.c:648
     [<00000000dc9c9d2e>] tls_init net/tls/tls_main.c:837 [inline]
     [<00000000dc9c9d2e>] tls_init+0x97/0x1f0 net/tls/tls_main.c:819
     [<000000009d663c39>] __tcp_set_ulp net/ipv4/tcp_ulp.c:126 [inline]
     [<000000009d663c39>] tcp_set_ulp+0xe2/0x190 net/ipv4/tcp_ulp.c:147
     [<00000000551f7621>] do_tcp_setsockopt.isra.0+0x19a/0xd60  
net/ipv4/tcp.c:2789
     [<00000000d02c41d7>] tcp_setsockopt+0x71/0x80 net/ipv4/tcp.c:3103
     [<0000000085d221c1>] sock_common_setsockopt+0x38/0x50  
net/core/sock.c:3129
     [<00000000d294eeda>] __sys_setsockopt+0x98/0x120 net/socket.c:2072
     [<00000000f1f1d607>] __do_sys_setsockopt net/socket.c:2083 [inline]
     [<00000000f1f1d607>] __se_sys_setsockopt net/socket.c:2080 [inline]
     [<00000000f1f1d607>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2080
     [<00000000fbd4f794>] do_syscall_64+0x76/0x1a0  
arch/x86/entry/common.c:301
     [<000000007383b736>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: memory leak
unreferenced object 0xffff88810e3e1c00 (size 512):
   comm "syz-executor.5", pid 7384, jiffies 4294944151 (age 13.290s)
   hex dump (first 32 bytes):
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
   backtrace:
     [<000000002f2bb8be>] kmemleak_alloc_recursive  
include/linux/kmemleak.h:55 [inline]
     [<000000002f2bb8be>] slab_post_alloc_hook mm/slab.h:439 [inline]
     [<000000002f2bb8be>] slab_alloc mm/slab.c:3326 [inline]
     [<000000002f2bb8be>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553
     [<00000000b76aef16>] kmalloc include/linux/slab.h:547 [inline]
     [<00000000b76aef16>] kzalloc include/linux/slab.h:742 [inline]
     [<00000000b76aef16>] create_ctx+0x25/0x70 net/tls/tls_main.c:648
     [<00000000dc9c9d2e>] tls_init net/tls/tls_main.c:837 [inline]
     [<00000000dc9c9d2e>] tls_init+0x97/0x1f0 net/tls/tls_main.c:819
     [<000000009d663c39>] __tcp_set_ulp net/ipv4/tcp_ulp.c:126 [inline]
     [<000000009d663c39>] tcp_set_ulp+0xe2/0x190 net/ipv4/tcp_ulp.c:147
     [<00000000551f7621>] do_tcp_setsockopt.isra.0+0x19a/0xd60  
net/ipv4/tcp.c:2789
     [<00000000d02c41d7>] tcp_setsockopt+0x71/0x80 net/ipv4/tcp.c:3103
     [<0000000085d221c1>] sock_common_setsockopt+0x38/0x50  
net/core/sock.c:3129
     [<00000000d294eeda>] __sys_setsockopt+0x98/0x120 net/socket.c:2072
     [<00000000f1f1d607>] __do_sys_setsockopt net/socket.c:2083 [inline]
     [<00000000f1f1d607>] __se_sys_setsockopt net/socket.c:2080 [inline]
     [<00000000f1f1d607>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2080
     [<00000000fbd4f794>] do_syscall_64+0x76/0x1a0  
arch/x86/entry/common.c:301
     [<000000007383b736>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: memory leak
unreferenced object 0xffff88811a0a7200 (size 512):
   comm "syz-executor.0", pid 7423, jiffies 4294944702 (age 7.780s)
   hex dump (first 32 bytes):
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
   backtrace:
     [<000000002f2bb8be>] kmemleak_alloc_recursive  
include/linux/kmemleak.h:55 [inline]
     [<000000002f2bb8be>] slab_post_alloc_hook mm/slab.h:439 [inline]
     [<000000002f2bb8be>] slab_alloc mm/slab.c:3326 [inline]
     [<000000002f2bb8be>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553
     [<00000000b76aef16>] kmalloc include/linux/slab.h:547 [inline]
     [<00000000b76aef16>] kzalloc include/linux/slab.h:742 [inline]
     [<00000000b76aef16>] create_ctx+0x25/0x70 net/tls/tls_main.c:648
     [<00000000dc9c9d2e>] tls_init net/tls/tls_main.c:837 [inline]
     [<00000000dc9c9d2e>] tls_init+0x97/0x1f0 net/tls/tls_main.c:819
     [<000000009d663c39>] __tcp_set_ulp net/ipv4/tcp_ulp.c:126 [inline]
     [<000000009d663c39>] tcp_set_ulp+0xe2/0x190 net/ipv4/tcp_ulp.c:147
     [<00000000551f7621>] do_tcp_setsockopt.isra.0+0x19a/0xd60  
net/ipv4/tcp.c:2789
     [<00000000d02c41d7>] tcp_setsockopt+0x71/0x80 net/ipv4/tcp.c:3103
     [<0000000085d221c1>] sock_common_setsockopt+0x38/0x50  
net/core/sock.c:3129
     [<00000000d294eeda>] __sys_setsockopt+0x98/0x120 net/socket.c:2072
     [<00000000f1f1d607>] __do_sys_setsockopt net/socket.c:2083 [inline]
     [<00000000f1f1d607>] __se_sys_setsockopt net/socket.c:2080 [inline]
     [<00000000f1f1d607>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2080
     [<00000000fbd4f794>] do_syscall_64+0x76/0x1a0  
arch/x86/entry/common.c:301
     [<000000007383b736>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Tested on:

commit:         0b58d013 bpf: tls, implement unhash to avoid transition ou..
git tree:       git://github.com/cilium/linux ktls-unhash
console output: https://syzkaller.appspot.com/x/log.txt?x=134f2e0ba00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=3bd5897d1df43b97
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)