================================================================== BUG: KASAN: slab-out-of-bounds in instrument_atomic_read include/linux/instrumented.h:72 [inline] BUG: KASAN: slab-out-of-bounds in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: slab-out-of-bounds in buffer_busy fs/buffer.c:2784 [inline] BUG: KASAN: slab-out-of-bounds in drop_buffers+0x70/0x49c fs/buffer.c:2796 Read of size 4 at addr ffff0000cabc1a60 by task syz.0.882/7798 CPU: 0 PID: 7798 Comm: syz.0.882 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026 Call trace: dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 print_address_description+0x88/0x218 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:420 kasan_report+0xa8/0xfc mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x258/0x290 mm/kasan/generic.c:189 __kasan_check_read+0x2c/0x3c mm/kasan/shadow.c:31 instrument_atomic_read include/linux/instrumented.h:72 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] buffer_busy fs/buffer.c:2784 [inline] drop_buffers+0x70/0x49c fs/buffer.c:2796 try_to_free_buffers+0x12c/0x2b0 fs/buffer.c:2835 filemap_release_folio+0x1ec/0x248 mm/filemap.c:4027 mapping_evict_folio+0x1a8/0x264 mm/truncate.c:303 invalidate_mapping_pagevec+0x2c0/0x50c mm/truncate.c:552 invalidate_mapping_pages+0x38/0x4c mm/truncate.c:591 drop_pagecache_sb+0x16c/0x220 fs/drop_caches.c:39 iterate_supers+0x11c/0x1d0 fs/super.c:757 drop_caches_sysctl_handler+0xb8/0x2fc fs/drop_caches.c:62 proc_sys_call_handler+0x400/0x6a4 fs/proc/proc_sysctl.c:602 proc_sys_write+0x2c/0x3c fs/proc/proc_sysctl.c:628 do_iter_readv_writev fs/read_write.c:-1 [inline] do_iter_write+0x53c/0x940 fs/read_write.c:861 vfs_iter_write+0x88/0xac fs/read_write.c:902 iter_file_splice_write+0x520/0xa7c fs/splice.c:685 do_splice_from fs/splice.c:763 [inline] direct_splice_actor+0xe4/0x134 fs/splice.c:950 splice_direct_to_actor+0x3a0/0x954 fs/splice.c:896 do_splice_direct+0x168/0x25c fs/splice.c:1002 do_sendfile+0x478/0xcc8 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1309 [inline] __arm64_sys_sendfile64+0x20c/0x36c fs/read_write.c:1309 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Allocated by task 7843: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:53 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc+0xec/0x178 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] iomap_page_create+0x1c4/0x47c fs/iomap/buffered-io.c:61 iomap_readpage_iter+0x1d8/0x820 fs/iomap/buffered-io.c:273 iomap_read_folio+0x2c0/0x68c fs/iomap/buffered-io.c:344 erofs_read_folio+0x100/0x310 fs/erofs/data.c:359 filemap_read_folio+0x134/0x384 mm/filemap.c:2490 do_read_cache_folio+0x24c/0x538 mm/filemap.c:3659 read_cache_folio+0x68/0x88 mm/filemap.c:3691 erofs_bread+0x13c/0x520 fs/erofs/data.c:50 erofs_find_target_block fs/erofs/namei.c:102 [inline] erofs_namei+0x218/0xc48 fs/erofs/namei.c:175 erofs_lookup+0x158/0x44c fs/erofs/namei.c:204 __lookup_slow+0x25c/0x38c fs/namei.c:1698 lookup_slow+0x5c/0x80 fs/namei.c:1715 walk_component fs/namei.c:2006 [inline] link_path_walk+0x794/0xcc0 fs/namei.c:2333 path_parentat fs/namei.c:2534 [inline] __filename_parentat+0x1d8/0x568 fs/namei.c:2558 filename_parentat fs/namei.c:2576 [inline] filename_create+0xd4/0x3a8 fs/namei.c:3865 do_mkdirat+0xac/0x3ec fs/namei.c:4129 __do_sys_mkdirat fs/namei.c:4154 [inline] __se_sys_mkdirat fs/namei.c:4152 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4152 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 The buggy address belongs to the object at ffff0000cabc1a00 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 96 bytes inside of 128-byte region [ffff0000cabc1a00, ffff0000cabc1a80) The buggy address belongs to the physical page: page:00000000b0e3e20c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10abc1 flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000200 0000000000000000 dead000000000001 ffff0000c0002300 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000cabc1900: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000cabc1980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff0000cabc1a00: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ^ ffff0000cabc1a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000cabc1b00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Unable to handle kernel paging request at virtual address fbd529d5a000000c KASAN: maybe wild-memory-access in range [0xdead4ead00000060-0xdead4ead00000067] Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 [fbd529d5a000000c] address between user and kernel address ranges Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 7798 Comm: syz.0.882 Tainted: G B syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026 pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--) pc : atomic_read include/linux/atomic/atomic-instrumented.h:28 [inline] pc : buffer_busy fs/buffer.c:2784 [inline] pc : drop_buffers+0x7c/0x49c fs/buffer.c:2796 lr : instrument_atomic_read include/linux/instrumented.h:72 [inline] lr : atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] lr : buffer_busy fs/buffer.c:2784 [inline] lr : drop_buffers+0x70/0x49c fs/buffer.c:2796 sp : ffff800021d16ec0 x29: ffff800021d16ef0 x28: ffff0000cabc1a00 x27: dfff800000000000 x26: 1fffff8000807fd1 x25: 1fffff8000807fd0 x24: 1fffff8000807fd1 x23: dead4ead00000000 x22: dfff800000000000 x21: fffffc000403fe80 x20: dead4ead00000060 x19: 0000000000000000 x18: ffff800011b8bf60 x17: 0000000000000000 x16: ffff80000804309c x15: 0000000000000002 x14: 0000000000000001 x13: 1ffff00002fbf96c x12: 0000000000080000 x11: 000000000007ffff x10: ffff800022d69000 x9 : 0000000000000003 x8 : 1bd5a9d5a000000c x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff800021d16898 x4 : ffff8000152f4cc0 x3 : ffff800008a9843c x2 : 0000000000000000 x1 : 0000000000000004 x0 : 0000000000000001 Call trace: atomic_read include/linux/atomic/atomic-instrumented.h:28 [inline] buffer_busy fs/buffer.c:2784 [inline] drop_buffers+0x7c/0x49c fs/buffer.c:2796 try_to_free_buffers+0x12c/0x2b0 fs/buffer.c:2835 filemap_release_folio+0x1ec/0x248 mm/filemap.c:4027 mapping_evict_folio+0x1a8/0x264 mm/truncate.c:303 invalidate_mapping_pagevec+0x2c0/0x50c mm/truncate.c:552 invalidate_mapping_pages+0x38/0x4c mm/truncate.c:591 drop_pagecache_sb+0x16c/0x220 fs/drop_caches.c:39 iterate_supers+0x11c/0x1d0 fs/super.c:757 drop_caches_sysctl_handler+0xb8/0x2fc fs/drop_caches.c:62 proc_sys_call_handler+0x400/0x6a4 fs/proc/proc_sysctl.c:602 proc_sys_write+0x2c/0x3c fs/proc/proc_sysctl.c:628 do_iter_readv_writev fs/read_write.c:-1 [inline] do_iter_write+0x53c/0x940 fs/read_write.c:861 vfs_iter_write+0x88/0xac fs/read_write.c:902 iter_file_splice_write+0x520/0xa7c fs/splice.c:685 do_splice_from fs/splice.c:763 [inline] direct_splice_actor+0xe4/0x134 fs/splice.c:950 splice_direct_to_actor+0x3a0/0x954 fs/splice.c:896 do_splice_direct+0x168/0x25c fs/splice.c:1002 do_sendfile+0x478/0xcc8 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1309 [inline] __arm64_sys_sendfile64+0x20c/0x36c fs/read_write.c:1309 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Code: 97f935b3 d343fe88 12000a89 11000d29 (38fb6908) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 97f935b3 bl 0xffffffffffe4d6cc 4: d343fe88 lsr x8, x20, #3 8: 12000a89 and w9, w20, #0x7 c: 11000d29 add w9, w9, #0x3 * 10: 38fb6908 ldrsb w8, [x8, x27] <-- trapping instruction