linux.git/fs/erofs, branch v6.11

erofs: fix out-of-bound access when z_erofs_gbuf_growsize() partially fails

2024-08-21T00:12:05+00:00

If z_erofs_gbuf_growsize() partially fails on a global buffer due to
memory allocation failure or fault injection (as reported by syzbot [1]),
new pages need to be freed by comparing to the existing pages to avoid
memory leaks.

However, the old gbuf->pages[] array may not be large enough, which can
lead to null-ptr-deref or out-of-bound access.

Fix this by checking against gbuf->nrpages in advance.

[1] https://lore.kernel.org/r/000000000000f7b96e062018c6e3@google.com

Reported-by: syzbot+242ee56aaa9585553766@syzkaller.appspotmail.com
Fixes: d6db47e571dc ("erofs: do not use pagepool in z_erofs_gbuf_growsize()")
Cc:  # 6.10+
Reviewed-by: Chunhai Guo 
Reviewed-by: Sandeep Dhavale 
Signed-off-by: Gao Xiang 
Link: https://lore.kernel.org/r/20240820085619.1375963-1-hsiangkao@linux.alibaba.com

erofs: allow large folios for compressed files

2024-08-19T08:10:04+00:00

As commit 2e6506e1c4ee ("mm/migrate: fix deadlock in
migrate_pages_batch() on large folios") has landed upstream, large
folios can be safely enabled for compressed inodes since all
prerequisites have already landed in 6.11-rc1.

Stress tests has been running on my fleet for over 20 days without any
regression.  Additionally, users [1] have requested it for months.
Let's allow large folios for EROFS full cases upstream now for wider
testing.

[1] https://lore.kernel.org/r/CAGsJ_4wtE8OcpinuqVwG4jtdx6Qh5f+TON6wz+4HMCq=A2qFcA@mail.gmail.com

Cc: Barry Song <21cnbao@gmail.com>
Cc: Matthew Wilcox (Oracle) 
[ Gao Xiang: minor commit typo fixes. ]
Signed-off-by: Gao Xiang 
Link: https://lore.kernel.org/r/20240819025207.3808649-1-hsiangkao@linux.alibaba.com

erofs: get rid of check_layout_compatibility()

2024-08-19T03:06:20+00:00

Simple enough to just open-code it.

Signed-off-by: Hongzhen Luo 
Reviewed-by: Sandeep Dhavale 
Reviewed-by: Gao Xiang 
Link: https://lore.kernel.org/r/20240806112208.150323-1-hongzhen@linux.alibaba.com
Signed-off-by: Gao Xiang

erofs: simplify readdir operation

2024-08-19T03:06:20+00:00

 - Use i_size instead of i_size_read() due to immutable fses;

 - Get rid of an unneeded goto since erofs_fill_dentries() also works;

 - Remove unnecessary lines.

Signed-off-by: Hongzhen Luo 
Link: https://lore.kernel.org/r/20240801112622.2164029-1-hongzhen@linux.alibaba.com
Reviewed-by: Gao Xiang 
Signed-off-by: Gao Xiang

erofs: convert comma to semicolon

2024-07-26T10:48:12+00:00

Replace a comma between expression statements by a semicolon.

Signed-off-by: Chen Ni 
Link: https://lore.kernel.org/r/20240724020721.2389738-1-nichen@iscas.ac.cn
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: support multi-page folios for erofs_bread()

2024-07-26T10:47:57+00:00

If the requested page is part of the previous multi-page folio, there
is no need to call read_mapping_folio() again.

Also, get rid of the remaining one of page->index [1] in our codebase.

[1] https://lore.kernel.org/r/Zp8fgUSIBGQ1TN0D@casper.infradead.org

Cc: Matthew Wilcox 
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang 
Link: https://lore.kernel.org/r/20240723073024.875290-1-hsiangkao@linux.alibaba.com

erofs: add support for FS_IOC_GETFSSYSFSPATH

2024-07-26T10:47:46+00:00

FS_IOC_GETFSSYSFSPATH ioctl exposes /sys/fs path of a given filesystem,
potentially standarizing sysfs reporting. This patch add support for
FS_IOC_GETFSSYSFSPATH for erofs, "erofs/" will be outputted for bdev
cases, "erofs/[domain_id,]" will be outputted for fscache cases.

Signed-off-by: Huang Xiaojia 
Link: https://lore.kernel.org/r/20240720082335.441563-1-huangxiaojia2@huawei.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: fix race in z_erofs_get_gbuf()

2024-07-26T10:47:33+00:00

In z_erofs_get_gbuf(), the current task may be migrated to another
CPU between `z_erofs_gbuf_id()` and `spin_lock(&gbuf->lock)`.

Therefore, z_erofs_put_gbuf() will trigger the following issue
which was found by stress test:

<2>[772156.434168] kernel BUG at fs/erofs/zutil.c:58!
..
<4>[772156.435007]
<4>[772156.439237] CPU: 0 PID: 3078 Comm: stress Kdump: loaded Tainted: G            E      6.10.0-rc7+ #2
<4>[772156.439239] Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 1.0.0 01/01/2017
<4>[772156.439241] pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
<4>[772156.439243] pc : z_erofs_put_gbuf+0x64/0x70 [erofs]
<4>[772156.439252] lr : z_erofs_lz4_decompress+0x600/0x6a0 [erofs]
..
<6>[772156.445958] stress (3127): drop_caches: 1
<4>[772156.446120] Call trace:
<4>[772156.446121]  z_erofs_put_gbuf+0x64/0x70 [erofs]
<4>[772156.446761]  z_erofs_lz4_decompress+0x600/0x6a0 [erofs]
<4>[772156.446897]  z_erofs_decompress_queue+0x740/0xa10 [erofs]
<4>[772156.447036]  z_erofs_runqueue+0x428/0x8c0 [erofs]
<4>[772156.447160]  z_erofs_readahead+0x224/0x390 [erofs]
..

Fixes: f36f3010f676 ("erofs: rename per-CPU buffers to global buffer pool and make it configurable")
Cc:  # 6.10+
Reviewed-by: Chunhai Guo 
Reviewed-by: Sandeep Dhavale 
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang 
Link: https://lore.kernel.org/r/20240722035110.3456740-1-hsiangkao@linux.alibaba.com

erofs: support STATX_DIOALIGN

2024-07-26T10:47:22+00:00

Add support for STATX_DIOALIGN to EROFS, so that direct I/O
alignment restrictions are exposed to userspace in a generic
way.

[Before]
```
./statx_test /mnt/erofs/testfile
statx(/mnt/erofs/testfile) = 0
dio mem align:0
dio offset align:0
```

[After]
```
./statx_test /mnt/erofs/testfile
statx(/mnt/erofs/testfile) = 0
dio mem align:512
dio offset align:512
```

Signed-off-by: Hongbo Li 
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang 
Link: https://lore.kernel.org/r/20240718083243.2485437-1-hsiangkao@linux.alibaba.com

erofs: silence uninitialized variable warning in z_erofs_scan_folio()

2024-07-13T04:47:34+00:00

Smatch complains that:

    fs/erofs/zdata.c:1047 z_erofs_scan_folio()
    error: uninitialized symbol 'err'.

The issue is if we hit this (!(map->m_flags & EROFS_MAP_MAPPED)) {
condition then "err" isn't set.  It's inside a loop so we would have to
hit that condition on every iteration.  Initialize "err" to zero to
solve this.

Fixes: 5b9654efb604 ("erofs: teach z_erofs_scan_folios() to handle multi-page folios")
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/f78ab50e-ed6d-4275-8dd4-a4159fa565a2@stanley.mountain
Signed-off-by: Gao Xiang