KCSAN: data-race in ext4_xattr_get / ext4_xattr_release

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in ext4_xattr_get / ext4_xattr_release_block ext4				2	1629d	1630d	0/26	closed as invalid on 2019/11/19 13:44
upstream	KCSAN: data-race in ext4_xattr_get / ext4_xattr_release_block (2) ext4				1	1609d	1609d	0/26	auto-closed as invalid on 2020/02/01 05:27

================================================================== BUG: KCSAN: data-race in ext4_xattr_get / ext4_xattr_release_block write to 0xffff8880a07e5004 of 4 bytes by task 7908 on cpu 1: ext4_xattr_release_block+0x15e/0x4b0 fs/ext4/xattr.c:1259 ext4_xattr_delete_inode+0x6e0/0x820 fs/ext4/xattr.c:2912 ext4_evict_inode+0x617/0xa40 fs/ext4/inode.c:281 evict+0x244/0x410 fs/inode.c:575 iput_final fs/inode.c:1571 [inline] iput+0x371/0x4e0 fs/inode.c:1597 do_unlinkat+0x378/0x530 fs/namei.c:4143 __do_sys_unlink fs/namei.c:4184 [inline] __se_sys_unlink fs/namei.c:4182 [inline] __x64_sys_unlink+0x3b/0x50 fs/namei.c:4182 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8880a07e5004 of 4 bytes by task 9624 on cpu 0: ext4_xattr_block_cache_insert fs/ext4/xattr.c:2959 [inline] ext4_xattr_block_get fs/ext4/xattr.c:537 [inline] ext4_xattr_get+0x31e/0x5c0 fs/ext4/xattr.c:652 ext4_xattr_security_get+0x3b/0x50 fs/ext4/xattr_security.c:20 __vfs_getxattr+0x9a/0xd0 fs/xattr.c:311 cap_inode_need_killpriv+0x3a/0x60 security/commoncap.c:300 security_inode_need_killpriv+0x5d/0x90 security/security.c:1327 dentry_needs_remove_privs.part.0+0x2d/0x80 fs/inode.c:1816 dentry_needs_remove_privs include/linux/fs.h:3561 [inline] file_remove_privs+0x1e9/0x2b0 fs/inode.c:1856 file_modified+0x22/0x80 fs/inode.c:1925 ext4_write_checks+0x4d/0x80 fs/ext4/file.c:249 ext4_buffered_write_iter+0x8a/0x290 fs/ext4/file.c:265 ext4_file_write_iter+0xfa/0xd70 fs/ext4/file.c:642 call_write_iter include/linux/fs.h:1901 [inline] do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693 do_iter_write fs/read_write.c:998 [inline] do_iter_write+0x13b/0x3c0 fs/read_write.c:979 vfs_iter_write+0x5c/0x80 fs/read_write.c:1039 iter_file_splice_write+0x536/0x850 fs/splice.c:760 do_splice_from fs/splice.c:863 [inline] direct_splice_actor+0xa0/0xc0 fs/splice.c:1037 splice_direct_to_actor+0x22b/0x540 fs/splice.c:992 do_splice_direct+0x161/0x1e0 fs/splice.c:1080 do_sendfile+0x384/0x7f0 fs/read_write.c:1520 __do_sys_sendfile64 fs/read_write.c:1581 [inline] __se_sys_sendfile64 fs/read_write.c:1567 [inline] __x64_sys_sendfile64+0x12a/0x140 fs/read_write.c:1567 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 9624 Comm: syz-executor.5 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================