ci2 starts bisection 2023-03-29 14:31:55.853593835 +0000 UTC m=+18216.867252834 bisecting fixing commit since 01f856ae6d0ca5ad0505b79bf2d22d7ca439b2a1 building syzkaller on 4c2a66e8f105ab184bc7ed6d8ca283a5a3c03045 ensuring issue is reproducible on original commit 01f856ae6d0ca5ad0505b79bf2d22d7ca439b2a1 testing commit 01f856ae6d0ca5ad0505b79bf2d22d7ca439b2a1 gcc compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 11ae105442c030fba7ef30921a07c0566b7ae3d4aa20fa070266c9b5cf7d694e run #0: crashed: KASAN: use-after-free Read in sysv_new_block run #1: crashed: KASAN: use-after-free Read in sysv_new_block run #2: crashed: KASAN: use-after-free Read in sysv_new_block run #3: crashed: KASAN: use-after-free Read in sysv_new_block run #4: crashed: KASAN: use-after-free Read in sysv_new_block run #5: crashed: KASAN: use-after-free Read in sysv_new_block run #6: crashed: KASAN: use-after-free Read in sysv_new_block run #7: crashed: KASAN: use-after-free Read in sysv_new_block run #8: crashed: KASAN: use-after-free Read in sysv_new_block run #9: crashed: KASAN: use-after-free Read in sysv_new_block run #10: crashed: KASAN: use-after-free Read in sysv_new_block run #11: crashed: KASAN: use-after-free Read in sysv_new_block run #12: crashed: KASAN: null-ptr-deref Write in get_block run #13: crashed: KASAN: use-after-free Read in sysv_new_block run #14: crashed: KASAN: use-after-free Read in sysv_new_block run #15: crashed: KASAN: use-after-free Read in sysv_new_block run #16: crashed: KASAN: use-after-free Read in sysv_new_block run #17: crashed: KASAN: use-after-free Read in sysv_new_block run #18: crashed: KASAN: use-after-free Read in sysv_new_block run #19: crashed: KASAN: null-ptr-deref Write in get_block testing current HEAD fcd476ea6a888ef6e6627f4c21a2ea8cca3e9312 testing commit fcd476ea6a888ef6e6627f4c21a2ea8cca3e9312 gcc compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 4e1e9de5712ea859656b0567a64b62f4f8f6bc209754abebc64c8d6137397209 run #0: crashed: KASAN: use-after-free Read in sysv_new_block run #1: crashed: KASAN: null-ptr-deref Write in get_block run #2: crashed: KASAN: use-after-free Read in sysv_new_block run #3: crashed: KASAN: use-after-free Read in sysv_new_block run #4: crashed: KASAN: use-after-free Read in sysv_new_block run #5: crashed: KASAN: use-after-free Read in sysv_new_block run #6: crashed: KASAN: null-ptr-deref Write in get_block run #7: crashed: KASAN: use-after-free Read in sysv_new_block run #8: crashed: KASAN: use-after-free Read in sysv_new_block run #9: crashed: KASAN: use-after-free Read in sysv_new_block revisions tested: 2, total time: 50m26.092730966s (build: 30m48.49378871s, test: 17m16.073970331s) the crash still happens on HEAD commit msg: Merge tag 'urgent-rcu.2023.03.28a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu crash: KASAN: use-after-free Read in sysv_new_block sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size ================================================================== BUG: KASAN: use-after-free in sysv_new_block+0x67e/0x8b0 Read of size 4 at addr ffff888070a290c8 by task syz-executor.0/14360 CPU: 0 PID: 14360 Comm: syz-executor.0 Not tainted 6.3.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: dump_stack_lvl+0x12e/0x1d0 print_report+0x163/0x510 kasan_report+0x108/0x140 sysv_new_block+0x67e/0x8b0 get_block+0x2cf/0x11f0 __block_write_begin_int+0x37f/0x1240 block_write_begin+0x72/0x150 sysv_write_begin+0x29/0x50 generic_perform_write+0x2b6/0x500 __generic_file_write_iter+0x143/0x340 generic_file_write_iter+0x9d/0x230 vfs_write+0x7be/0xb10 ksys_write+0x122/0x200 do_syscall_64+0x41/0xc0 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fb2acc8c0d9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb2ada5c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fb2acdabf80 RCX: 00007fb2acc8c0d9 RDX: 00000000fffffd5e RSI: 000000002000ad00 RDI: 0000000000000004 RBP: 00007fb2acce7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd56d14ddf R14: 00007fb2ada5c300 R15: 0000000000022000 The buggy address belongs to the physical page: page:ffffea0001c28a40 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x70a29 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), pid 11685, tgid 11684 (syz-executor.0), ts 264769663805, free_ts 264772992138 get_page_from_freelist+0x31e9/0x3360 __alloc_pages+0x255/0x670 __folio_alloc+0x13/0x30 vma_alloc_folio+0x308/0x680 handle_mm_fault+0x2afa/0x3d50 exc_page_fault+0x5a4/0x7b0 asm_exc_page_fault+0x26/0x30 page last free stack trace: free_unref_page_prepare+0xe2f/0xe70 free_unref_page_list+0x596/0x830 release_pages+0x1a07/0x1bc0 tlb_flush_mmu+0xe9/0x1e0 tlb_finish_mmu+0xb6/0x1c0 unmap_region+0x221/0x270 do_vmi_align_munmap+0x937/0xec0 do_vmi_munmap+0x199/0x1f0 __vm_munmap+0x1cc/0x2b0 __x64_sys_munmap+0x5b/0x70 do_syscall_64+0x41/0xc0 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888070a28f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888070a29000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888070a29080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888070a29100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888070a29180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================