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KCSAN: data-race in proc_evict_inode / proc_pid_permission

Status: auto-obsoleted due to no activity on 2023/04/03 17:17
Subsystems: kernel
[Documentation on labels]
First crash: 721d, last: 721d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in proc_evict_inode / proc_pid_permission

write to 0xffff88810aeee5e0 of 8 bytes by task 3124 on cpu 1:
 proc_evict_inode+0x4d/0xe0
 evict+0x1aa/0x410
 iput+0x42c/0x5b0
 dentry_unlink_inode+0x22a/0x240
 __dentry_kill+0x2db/0x4a0
 shrink_dentry_list+0x207/0x380
 prune_dcache_sb+0x81/0xb0
 super_cache_scan+0x26c/0x310
 do_shrink_slab+0x2a0/0x640
 shrink_slab+0x2bc/0x520
 shrink_node+0xaf5/0x14f0
 do_try_to_free_pages+0x40d/0xc80
 try_to_free_mem_cgroup_pages+0x1e2/0x480
 reclaim_high+0xca/0x110
 mem_cgroup_handle_over_high+0x8c/0x1a0
 exit_to_user_mode_loop+0x99/0xe0
 exit_to_user_mode_prepare+0x6a/0xa0
 irqentry_exit_to_user_mode+0x9/0x20
 irqentry_exit+0x12/0x40
 asm_exc_page_fault+0x26/0x30

read to 0xffff88810aeee5e0 of 8 bytes by task 26982 on cpu 0:
 proc_pid_permission+0x42/0x1a0
 inode_permission+0x184/0x300
 link_path_walk+0x162/0x860
 path_openat+0x19c/0x1b70
 do_filp_open+0xf6/0x200
 do_sys_openat2+0xb5/0x2a0
 __x64_sys_openat+0xf3/0x120
 do_syscall_64+0x41/0xc0
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xffff88816294d300 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 26982 Comm: syz-executor.5 Tainted: G        W          6.2.0-rc7-syzkaller-00002-gd2d11f342b17-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
==================================================================
9pnet_fd: Insufficient options for proto=fd

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/06 16:52 upstream d2d11f342b17 0a9c11b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in proc_evict_inode / proc_pid_permission
* Struck through repros no longer work on HEAD.