================================================================== BUG: KASAN: slab-out-of-bounds in tcp_retransmit_timer+0x2d30/0x3220 net/ipv4/tcp_timer.c:500 Read of size 8 at addr ffff88809c3882d0 by task syz-executor.4/31960 CPU: 1 PID: 31960 Comm: syz-executor.4 Not tainted 5.9.0-rc1-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+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 tcp_retransmit_timer+0x2d30/0x3220 net/ipv4/tcp_timer.c:500 tcp_write_timer_handler+0x79b/0xa60 net/ipv4/tcp_timer.c:611 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:631 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1413 expire_timers kernel/time/timer.c:1458 [inline] __run_timers.part.0+0x67c/0xaa0 kernel/time/timer.c:1755 __run_timers kernel/time/timer.c:1736 [inline] run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1768 __do_softirq+0x2de/0xa24 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x9d/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x1f3/0x230 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:lockdep_init_map_waits+0xa/0x8a0 kernel/locking/lockdep.c:4177 Code: 00 48 8b 74 24 08 e9 bf f6 ff ff 4c 89 e7 e8 0d 19 5a 00 e9 8e f6 ff ff 0f 1f 84 00 00 00 00 00 48 b8 00 00 00 00 00 fc ff df <41> 55 41 89 cd 41 54 49 89 d4 55 48 89 fd 48 83 c7 08 48 89 fa 53 RSP: 0018:ffffc900062a7ae8 EFLAGS: 00000282 RAX: dffffc0000000000 RBX: ffff888058159578 RCX: 0000000000000000 RDX: ffffffff89d2b2f8 RSI: ffffffff88577940 RDI: ffff8880581596c8 RBP: ffff888058159784 R08: 0000000000000003 R09: 0000000000000000 R10: ffffed100b02b2cd R11: 0000000000000001 R12: 0000000000000000 R13: ffff8880581597a0 R14: ffff8880985f4028 R15: ffff8880554ae4b8 inode_init_always+0x74d/0xd10 fs/inode.c:177 alloc_inode+0x82/0x230 fs/inode.c:239 new_inode_pseudo fs/inode.c:928 [inline] new_inode+0x27/0x2f0 fs/inode.c:957 __ext4_new_inode+0x3f6/0x5390 fs/ext4/ialloc.c:842 ext4_symlink+0x4b0/0xe10 fs/ext4/namei.c:3303 vfs_symlink fs/namei.c:3959 [inline] vfs_symlink+0x44e/0x690 fs/namei.c:3945 do_symlinkat+0x258/0x2c0 fs/namei.c:3986 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d2e7 Code: 0f 1f 00 b8 5c 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 1d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 58 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 fd b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffcc9026238 EFLAGS: 00000202 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045d2e7 RDX: 00007ffcc90262d3 RSI: 00000000004c30cd RDI: 00007ffcc90262c0 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000013 R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000001 R13: 00007ffcc9026270 R14: 0000000000000000 R15: 00007ffcc9026280 Allocated by task 6897: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 slab_post_alloc_hook mm/slab.h:518 [inline] slab_alloc mm/slab.c:3312 [inline] kmem_cache_alloc+0x138/0x3a0 mm/slab.c:3482 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags fs/namei.c:2646 [inline] user_path_at_empty+0xa1/0x100 fs/namei.c:2646 user_path_at include/linux/namei.h:59 [inline] vfs_statx+0x14e/0x390 fs/stat.c:202 vfs_lstat include/linux/fs.h:3175 [inline] __do_sys_newlstat+0x91/0x110 fs/stat.c:374 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 6897: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422 __cache_free mm/slab.c:3418 [inline] kmem_cache_free.part.0+0x67/0x1f0 mm/slab.c:3693 putname+0xe1/0x120 fs/namei.c:259 filename_lookup+0x3b1/0x560 fs/namei.c:2376 user_path_at include/linux/namei.h:59 [inline] vfs_statx+0x14e/0x390 fs/stat.c:202 vfs_lstat include/linux/fs.h:3175 [inline] __do_sys_newlstat+0x91/0x110 fs/stat.c:374 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88809c388e00 which belongs to the cache names_cache of size 4096 The buggy address is located 2864 bytes to the left of 4096-byte region [ffff88809c388e00, ffff88809c389e00) The buggy address belongs to the page: page:00000000eee81010 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9c388 head:00000000eee81010 order:1 compound_mapcount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea0002745d88 ffffea0000e20408 ffff8880aa241c00 raw: 0000000000000000 ffff88809c388e00 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809c388180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809c388200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88809c388280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809c388300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809c388380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================