KASAN: null-ptr-deref Write in x25

Title	Replies (including bot)	Last reply
[PATCH 4.19 00/92] 4.19.100-stable review	98 (98)	2020/01/31 13:57
[PATCH 4.9 000/271] 4.9.212-stable review	283 (283)	2020/01/29 22:35
[PATCH 5.4 000/104] 5.4.16-stable review	113 (113)	2020/01/29 15:36
[PATCH 4.14 00/46] 4.14.169-stable review	51 (51)	2020/01/29 14:42
[PATCH 4.4 000/183] 4.4.212-stable review	190 (190)	2020/01/29 13:12
[PATCH] net/x25: fix nonblocking connect	2 (2)	2020/01/10 02:40
[PATCH 1/4] [net-next] wan: remove stale Kconfig entries	12 (12)	2019/12/11 13:34
KASAN: null-ptr-deref Write in x25_connect	1 (2)	2019/12/06 12:41

================================================================== BUG: KASAN: null-ptr-deref in atomic_fetch_sub include/asm-generic/atomic-instrumented.h:199 [inline] BUG: KASAN: null-ptr-deref in refcount_sub_and_test include/linux/refcount.h:253 [inline] BUG: KASAN: null-ptr-deref in refcount_dec_and_test include/linux/refcount.h:281 [inline] BUG: KASAN: null-ptr-deref in x25_neigh_put include/net/x25.h:252 [inline] BUG: KASAN: null-ptr-deref in x25_connect+0x974/0x1020 net/x25/af_x25.c:820 Write of size 4 at addr 00000000000000c8 by task syz-executor.5/32400 CPU: 1 PID: 32400 Comm: syz-executor.5 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 __kasan_report.cold+0x5/0x41 mm/kasan/report.c:510 kasan_report+0x12/0x20 mm/kasan/common.c:634 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 __kasan_check_write+0x14/0x20 mm/kasan/common.c:98 atomic_fetch_sub include/asm-generic/atomic-instrumented.h:199 [inline] refcount_sub_and_test include/linux/refcount.h:253 [inline] refcount_dec_and_test include/linux/refcount.h:281 [inline] x25_neigh_put include/net/x25.h:252 [inline] x25_connect+0x974/0x1020 net/x25/af_x25.c:820 __sys_connect_file+0x25d/0x2e0 net/socket.c:1847 __sys_connect+0x51/0x90 net/socket.c:1860 __do_sys_connect net/socket.c:1871 [inline] __se_sys_connect net/socket.c:1868 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1868 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fa58a10ec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679 RDX: 0000000000000012 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa58a10f6d4 R13: 00000000004c0f1c R14: 00000000004d4088 R15: 00000000ffffffff ==================================================================