================================================================== 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 ffffc9000aaef594 by task syz-executor.4/5539 CPU: 0 PID: 5539 Comm: syz-executor.4 Not tainted 6.6.0-rc3-next-20230929-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 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 generic_perform_write+0x2e9/0x600 mm/filemap.c:3964 ext4_buffered_write_iter+0x11f/0x3c0 fs/ext4/file.c:299 ext4_file_write_iter+0x7f7/0x1860 fs/ext4/file.c:717 __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 irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:309 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564 RIP: 0033:0x7ff717a7caf1 Code: 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 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:0000000020000090 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007ff717b9bf80 RCX: 00007ff717a7cae9 RDX: 00000000200000c0 RSI: 0000000020000090 RDI: 0000000043182000 RBP: 00007ff717ac847a R08: 0000000020000140 R09: 0000000020000140 R10: 0000000020000100 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007ff717b9bf80 R15: 00007ffcf1ee0af8 The buggy address belongs to stack of task syz-executor.4/5539 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 [ffffc9000aae8000, ffffc9000aaf1000) created by: kernel_clone+0xfd/0x920 kernel/fork.c:2902 The buggy address belongs to the physical page: page:ffffea0000a48440 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29211 memcg:ffff88802097c082 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff ffff88802097c082 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 5094, tgid 5094 (syz-executor.5), ts 305817121800, free_ts 286910529668 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x98f/0x32a0 mm/page_alloc.c:3333 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4589 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 __do_sys_clone+0xba/0x100 kernel/fork.c:3045 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 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1134 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2383 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2518 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x180/0x3e0 mm/slub.c:3523 __alloc_skb+0x287/0x330 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1286 [inline] nlmsg_new include/net/netlink.h:999 [inline] rtmsg_ifinfo_build_skb+0x7d/0x270 net/core/rtnetlink.c:4067 rtmsg_ifinfo_event net/core/rtnetlink.c:4110 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4100 [inline] rtmsg_ifinfo+0x9f/0x1a0 net/core/rtnetlink.c:4119 netdev_state_change net/core/dev.c:1354 [inline] netdev_state_change+0x12b/0x140 net/core/dev.c:1345 linkwatch_do_dev+0x122/0x150 net/core/link_watch.c:182 __linkwatch_run_queue+0x233/0x680 net/core/link_watch.c:235 linkwatch_event+0x8f/0xc0 net/core/link_watch.c:278 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 Memory state around the buggy address: ffffc9000aaef480: f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc9000aaef500: 00 00 00 00 00 f1 f1 f1 f1 f1 f1 00 f2 f2 f2 00 >ffffc9000aaef580: 00 f2 f2 00 00 00 00 00 f3 f3 f3 f3 f3 00 00 00 ^ ffffc9000aaef600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc9000aaef680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 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