================================================================== BUG: KFENCE: out-of-bounds read in memcpy+0xc/0x20 arch/x86/lib/memcpy_64.S:37 Out-of-bounds read at 0xffff88823bd73000 (512B right of kfence-#184): memcpy+0xc/0x20 arch/x86/lib/memcpy_64.S:37 memcpy_from_iter lib/iov_iter.c:73 [inline] iterate_bvec include/linux/iov_iter.h:122 [inline] iterate_and_advance2 include/linux/iov_iter.h:249 [inline] iterate_and_advance include/linux/iov_iter.h:271 [inline] __copy_from_iter lib/iov_iter.c:249 [inline] copy_page_from_iter_atomic+0x8b8/0x1130 lib/iov_iter.c:481 generic_perform_write+0x2ee/0x620 mm/filemap.c:3982 shmem_file_write_iter+0x114/0x140 mm/shmem.c:2920 call_write_iter include/linux/fs.h:2110 [inline] do_iter_readv_writev+0x507/0x780 fs/read_write.c:741 vfs_iter_write+0x1eb/0x990 fs/read_write.c:895 lo_write_bvec drivers/block/loop.c:246 [inline] lo_write_simple drivers/block/loop.c:267 [inline] do_req_filebacked drivers/block/loop.c:491 [inline] loop_handle_cmd drivers/block/loop.c:1907 [inline] loop_process_work+0x1577/0x20c0 drivers/block/loop.c:1942 process_one_work+0x9ac/0x1ac0 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c4/0x3a0 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 kfence-#184: 0xffff88823bd72e00-0xffff88823bd72fff, size=512, cache=kmalloc-512 allocated by task 6008 on cpu 0 at 1179.058712s: kmalloc include/linux/slab.h:632 [inline] hfsplus_read_wrapper+0x37d/0x1070 fs/hfsplus/wrapper.c:179 hfsplus_fill_super+0x352/0x1bc0 fs/hfsplus/super.c:419 mount_bdev+0x1e6/0x2d0 fs/super.c:1658 legacy_get_tree+0x10c/0x220 fs/fs_context.c:662 vfs_get_tree+0x92/0x380 fs/super.c:1779 do_new_mount fs/namespace.c:3352 [inline] path_mount+0x14e6/0x1f20 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __x64_sys_mount+0x297/0x320 fs/namespace.c:3875 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 0 PID: 5155 Comm: kworker/u8:0 Not tainted 6.9.0-rc5-syzkaller-00007-g4d2008430ce8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: loop0 loop_rootcg_workfn RIP: 0010:memcpy+0xc/0x20 arch/x86/lib/memcpy_64.S:38 Code: 2d 18 8f e8 f6 1f d5 f9 e9 53 fd ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 48 89 f8 48 89 d1 a4 e9 f8 19 34 00 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 RSP: 0018:ffffc90004c976e8 EFLAGS: 00010206 RAX: ffff888076388200 RBX: dffffc0000000000 RCX: 0000000000000600 RDX: 0000000000000600 RSI: ffff88823bd73000 RDI: ffff888076388200 RBP: ffffc90004c97bc8 R08: 0000000000000001 R09: 0000000000000002 R10: 0000000000000002 R11: 0000000000000004 R12: ffffc90004c97bd0 R13: 0000000000000600 R14: 0000000000000600 R15: 0000000000000600 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff88823bd73000 CR3: 000000002290a000 CR4: 0000000000350ef0 Call Trace: memcpy_from_iter lib/iov_iter.c:73 [inline] iterate_bvec include/linux/iov_iter.h:122 [inline] iterate_and_advance2 include/linux/iov_iter.h:249 [inline] iterate_and_advance include/linux/iov_iter.h:271 [inline] __copy_from_iter lib/iov_iter.c:249 [inline] copy_page_from_iter_atomic+0x8b8/0x1130 lib/iov_iter.c:481 generic_perform_write+0x2ee/0x620 mm/filemap.c:3982 shmem_file_write_iter+0x114/0x140 mm/shmem.c:2920 call_write_iter include/linux/fs.h:2110 [inline] do_iter_readv_writev+0x507/0x780 fs/read_write.c:741 vfs_iter_write+0x1eb/0x990 fs/read_write.c:895 lo_write_bvec drivers/block/loop.c:246 [inline] lo_write_simple drivers/block/loop.c:267 [inline] do_req_filebacked drivers/block/loop.c:491 [inline] loop_handle_cmd drivers/block/loop.c:1907 [inline] loop_process_work+0x1577/0x20c0 drivers/block/loop.c:1942 process_one_work+0x9ac/0x1ac0 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c4/0x3a0 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 18 8f e8 f6 1f d5 sbb %cl,-0x2ae00918(%rdi) 6: f9 stc 7: e9 53 fd ff ff jmp 0xfffffd5f c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: f3 0f 1e fa endbr64 21: 66 90 xchg %ax,%ax 23: 48 89 f8 mov %rdi,%rax 26: 48 89 d1 mov %rdx,%rcx * 29: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2b: e9 f8 19 34 00 jmp 0x341a28 30: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) 37: 00 00 00 00 3b: 66 90 xchg %ax,%ax 3d: 90 nop 3e: 90 nop