================================================================== BUG: KASAN: stack-out-of-bounds in iterate_bvec include/linux/iov_iter.h:116 [inline] BUG: KASAN: stack-out-of-bounds in __copy_from_iter_mc+0x30a/0x3f0 lib/iov_iter.c:262 Read of size 4 at addr ffffc90015a6f574 by task syz-executor.5/7460 CPU: 0 PID: 7460 Comm: syz-executor.5 Not tainted 6.6.0-rc3-next-20230926-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 iterate_bvec include/linux/iov_iter.h:116 [inline] __copy_from_iter_mc+0x30a/0x3f0 lib/iov_iter.c:262 __copy_from_iter lib/iov_iter.c:271 [inline] copy_page_from_iter_atomic+0x471/0x11e0 lib/iov_iter.c:504 btrfs_copy_from_user+0xe7/0x310 fs/btrfs/file.c:61 btrfs_buffered_write+0xabe/0x12d0 fs/btrfs/file.c:1337 btrfs_do_write_iter+0xa56/0x1120 fs/btrfs/file.c:1686 __kernel_write_iter+0x261/0x7e0 fs/read_write.c:517 dump_emit_page fs/coredump.c:888 [inline] dump_user_range+0x299/0x790 fs/coredump.c:915 elf_core_dump+0x2700/0x3900 fs/binfmt_elf.c:2142 do_coredump+0x2c97/0x3fc0 fs/coredump.c:764 get_signal+0x2434/0x2790 kernel/signal.c:2890 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f29d267cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f29d33670c8 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffe5 RBX: 00007f29d279bf80 RCX: 00007f29d267cae9 RDX: 0000000100000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f29d26c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f29d279bf80 R15: 00007fffa1fc8c78 The buggy address belongs to stack of task syz-executor.5/7460 and is located at offset 108 in frame: dump_user_range+0x0/0x790 fs/coredump.c:482 This frame has 3 objects: [48, 56) 'pos' [80, 96) 'bvec' [112, 152) 'iter' The buggy address belongs to the virtual mapping at [ffffc90015a68000, ffffc90015a71000) created by: kernel_clone+0xfd/0x920 kernel/fork.c:2902 The buggy address belongs to the physical page: page:ffffea0000a91ac0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a46b memcg:ffff888074b04882 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff ffff888074b04882 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 2, tgid 2 (kthreadd), ts 409457561721, free_ts 402582339324 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1530 prep_new_page mm/page_alloc.c:1537 [inline] get_page_from_freelist+0xf17/0x2e50 mm/page_alloc.c:3200 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4456 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2304 vm_area_alloc_pages mm/vmalloc.c:3063 [inline] __vmalloc_area_node mm/vmalloc.c:3139 [inline] __vmalloc_node_range+0x8f3/0x1bf0 mm/vmalloc.c:3320 alloc_thread_stack_node kernel/fork.c:309 [inline] dup_task_struct kernel/fork.c:1118 [inline] copy_process+0x13e3/0x74b0 kernel/fork.c:2327 kernel_clone+0xfd/0x920 kernel/fork.c:2902 kernel_thread+0xc0/0x100 kernel/fork.c:2964 create_kthread kernel/kthread.c:411 [inline] kthreadd+0x4fb/0x7d0 kernel/kthread.c:764 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1130 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2342 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2435 vfree mm/vmalloc.c:2842 [inline] vfree+0x3fb/0xe40 mm/vmalloc.c:2807 snd_dma_free_pages+0xcf/0x130 sound/core/memalloc.c:126 do_free_pages sound/core/pcm_memory.c:93 [inline] do_free_pages sound/core/pcm_memory.c:88 [inline] snd_pcm_lib_free_pages+0x216/0x450 sound/core/pcm_memory.c:499 do_hw_free sound/core/pcm_native.c:876 [inline] snd_pcm_release_substream.part.0+0x29c/0x330 sound/core/pcm_native.c:2709 snd_pcm_release_substream+0x5b/0x70 sound/core/pcm_native.c:2703 snd_pcm_oss_release_file sound/core/oss/pcm_oss.c:2413 [inline] snd_pcm_oss_release_file sound/core/oss/pcm_oss.c:2405 [inline] snd_pcm_oss_release+0x13b/0x310 sound/core/oss/pcm_oss.c:2592 __fput+0x3f7/0xa70 fs/file_table.c:384 __fput_sync+0x47/0x50 fs/file_table.c:465 __do_sys_close fs/open.c:1572 [inline] __se_sys_close fs/open.c:1557 [inline] __x64_sys_close+0x87/0xf0 fs/open.c:1557 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffffc90015a6f400: f1 f1 f1 00 00 00 00 00 00 f3 f3 f3 f3 00 00 00 ffffc90015a6f480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc90015a6f500: 00 f1 f1 f1 f1 f1 f1 00 f2 f2 f2 00 00 f2 f2 00 ^ ffffc90015a6f580: 00 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 ffffc90015a6f600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 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