Gao Xiang 2f44013e39 erofs: fix pcluster use-after-free on UP platforms ... During stress testing with CONFIG_SMP disabled, KASAN reports as below: ================================================================== BUG: KASAN: use-after-free in __mutex_lock+0xe5/0xc30 Read of size 8 at addr ffff8881094223f8 by task stress/7789 CPU: 0 PID: 7789 Comm: stress Not tainted 6.0.0-rc1-00002-g0d53d2e882f9 #3 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 Call Trace: <TASK> .. __mutex_lock+0xe5/0xc30 .. z_erofs_do_read_page+0x8ce/0x1560 .. z_erofs_readahead+0x31c/0x580 .. Freed by task 7787 kasan_save_stack+0x1e/0x40 kasan_set_track+0x20/0x30 kasan_set_free_info+0x20/0x40 __kasan_slab_free+0x10c/0x190 kmem_cache_free+0xed/0x380 rcu_core+0x3d5/0xc90 __do_softirq+0x12d/0x389 Last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0x97/0xb0 call_rcu+0x3d/0x3f0 erofs_shrink_workstation+0x11f/0x210 erofs_shrink_scan+0xdc/0x170 shrink_slab.constprop.0+0x296/0x530 drop_slab+0x1c/0x70 drop_caches_sysctl_handler+0x70/0x80 proc_sys_call_handler+0x20a/0x2f0 vfs_write+0x555/0x6c0 ksys_write+0xbe/0x160 do_syscall_64+0x3b/0x90 The root cause is that erofs_workgroup_unfreeze() doesn't reset to orig_val thus it causes a race that the pcluster reuses unexpectedly before freeing. Since UP platforms are quite rare now, such path becomes unnecessary. Let's drop such specific-designed path directly instead. Fixes: 73f5c66df3 ("staging: erofs: fix `erofs_workgroup_{try_to_freeze, unfreeze}'") Reviewed-by: Yue Hu <huyue2@coolpad.com> Reviewed-by: Chao Yu <chao@kernel.org> Link: https://lore.kernel.org/r/20220902045710.109530-1-hsiangkao@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>		2022-09-05 23:23:30 +08:00
..
compress.h	erofs: introduce multi-reference pclusters (fully-referenced)	2022-07-22 21:44:27 +08:00
data.c	erofs: get rid of erofs_prepare_dio() helper	2022-07-22 21:46:03 +08:00
decompressor_lzma.c	erofs: wake up all waiters after z_erofs_lzma_head ready	2022-07-09 06:32:29 +08:00
decompressor.c	erofs: introduce multi-reference pclusters (fully-referenced)	2022-07-22 21:44:27 +08:00
dir.c	erofs: update ctx->pos for every emitted dirent	2022-07-31 22:26:29 +08:00
erofs_fs.h	erofs: scan devices from device table	2022-05-18 00:11:21 +08:00
fscache.c	erofs: fix error return code in erofs_fscache_{meta_,}read_folio	2022-09-05 23:21:15 +08:00
inode.c	erofs: leave compressed inodes unsupported in fscache mode for now	2022-05-29 15:34:54 +08:00
internal.h	erofs: fix pcluster use-after-free on UP platforms	2022-09-05 23:23:30 +08:00
Kconfig	erofs: register fscache volume	2022-05-18 00:11:19 +08:00
Makefile	erofs: register fscache volume	2022-05-18 00:11:19 +08:00
namei.c	erofs: make filesystem exportable	2022-05-17 23:48:54 +08:00
pcpubuf.c	erofs: get rid of ->lru usage	2021-10-25 08:22:59 +08:00
super.c	dax: introduce holder for dax_device	2022-07-17 17:14:30 -07:00
sysfs.c	erofs: add 'fsid' mount option	2022-05-18 00:11:21 +08:00
tagptr.h	erofs: clean up file headers & footers	2021-06-08 00:41:24 +08:00
utils.c	mm: shrinkers: provide shrinkers with names	2022-07-03 18:08:40 -07:00
xattr.c	erofs: use meta buffers for xattr operations	2022-01-04 23:47:08 +08:00
xattr.h	erofs: use meta buffers for xattr operations	2022-01-04 23:47:08 +08:00
zdata.c	erofs: introduce multi-reference pclusters (fully-referenced)	2022-07-22 21:44:27 +08:00
zdata.h	erofs: introduce multi-reference pclusters (fully-referenced)	2022-07-22 21:44:27 +08:00
zmap.c	erofs: avoid the potentially wrong m_plen for big pcluster	2022-09-05 23:22:01 +08:00