linux.git/fs/erofs, branch v5.8

erofs: fix partially uninitialized misuse in z_erofs_onlinepage_fixup

2020-06-24T01:47:44+00:00

Hongyu reported "id != index" in z_erofs_onlinepage_fixup() with
specific aarch64 environment easily, which wasn't shown before.

After digging into that, I found that high 32 bits of page->private
was set to 0xaaaaaaaa rather than 0 (due to z_erofs_onlinepage_init
behavior with specific compiler options). Actually we only use low
32 bits to keep the page information since page->private is only 4
bytes on most 32-bit platforms. However z_erofs_onlinepage_fixup()
uses the upper 32 bits by mistake.

Let's fix it now.

Reported-and-tested-by: Hongyu Jin 
Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support")
Cc:  # 4.19+
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20200618234349.22553-1-hsiangkao@aol.com
Signed-off-by: Gao Xiang

Merge tag 'erofs-for-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

2020-06-03T03:16:55+00:00

Pull erofs updates from Gao Xiang:
 "The most interesting part is the new mount api conversion, which is
  actually a old patch already pending for several cycles. And the
  others are recent trivial cleanups here.

  Summary:

   - Convert to use the new mount apis

   - Some random cleanup patches"

* tag 'erofs-for-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: suppress false positive last_block warning
  erofs: convert to use the new mount fs_context api
  erofs: code cleanup by removing ifdef macro surrounding

mm: remove the prot argument from vm_map_ram

2020-06-02T17:59:11+00:00

This is always PAGE_KERNEL - for long term mappings with other properties
vmap should be used.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Acked-by: Peter Zijlstra (Intel) 
Cc: Christian Borntraeger 
Cc: Christophe Leroy 
Cc: Daniel Vetter 
Cc: David Airlie 
Cc: Gao Xiang 
Cc: Greg Kroah-Hartman 
Cc: Haiyang Zhang 
Cc: Johannes Weiner 
Cc: "K. Y. Srinivasan" 
Cc: Laura Abbott 
Cc: Mark Rutland 
Cc: Michael Kelley 
Cc: Minchan Kim 
Cc: Nitin Gupta 
Cc: Robin Murphy 
Cc: Sakari Ailus 
Cc: Stephen Hemminger 
Cc: Sumit Semwal 
Cc: Wei Liu 
Cc: Benjamin Herrenschmidt 
Cc: Catalin Marinas 
Cc: Heiko Carstens 
Cc: Paul Mackerras 
Cc: Vasily Gorbik 
Cc: Will Deacon 
Link: http://lkml.kernel.org/r/20200414131348.444715-19-hch@lst.de
Signed-off-by: Linus Torvalds

erofs: convert compressed files from readpages to readahead

2020-06-02T17:59:07+00:00

Use the new readahead operation in erofs.

Signed-off-by: Matthew Wilcox (Oracle) 
Signed-off-by: Andrew Morton 
Reviewed-by: Dave Chinner 
Reviewed-by: William Kucharski 
Reviewed-by: Chao Yu 
Acked-by: Gao Xiang 
Cc: Christoph Hellwig 
Cc: Cong Wang 
Cc: Darrick J. Wong 
Cc: Eric Biggers 
Cc: Jaegeuk Kim 
Cc: John Hubbard 
Cc: Joseph Qi 
Cc: Junxiao Bi 
Cc: Michal Hocko 
Cc: Zi Yan 
Cc: Johannes Thumshirn 
Cc: Miklos Szeredi 
Link: http://lkml.kernel.org/r/20200414150233.24495-20-willy@infradead.org
Signed-off-by: Linus Torvalds

erofs: convert uncompressed files from readpages to readahead

2020-06-02T17:59:07+00:00

Use the new readahead operation in erofs

Signed-off-by: Matthew Wilcox (Oracle) 
Signed-off-by: Andrew Morton 
Reviewed-by: William Kucharski 
Reviewed-by: Chao Yu 
Acked-by: Gao Xiang 
Cc: Christoph Hellwig 
Cc: Cong Wang 
Cc: Darrick J. Wong 
Cc: Dave Chinner 
Cc: Eric Biggers 
Cc: Jaegeuk Kim 
Cc: John Hubbard 
Cc: Joseph Qi 
Cc: Junxiao Bi 
Cc: Michal Hocko 
Cc: Zi Yan 
Cc: Johannes Thumshirn 
Cc: Miklos Szeredi 
Link: http://lkml.kernel.org/r/20200414150233.24495-19-willy@infradead.org
Signed-off-by: Linus Torvalds

erofs: suppress false positive last_block warning

2020-05-29T10:58:13+00:00

As Andrew mentioned, some rare specific gcc versions could report
last_block uninitialized warning. Actually last_block doesn't need
to be uninitialized first from its implementation due to bio == NULL
condition. After a bio is allocated, last_block will be assigned
then.

The detailed analysis is in this thread [1]. So let's silence those
confusing gccs simply.

[1] https://lore.kernel.org/r/20200421072839.GA13867@hsiangkao-HP-ZHAN-66-Pro-G1

Cc: Andrew Morton 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20200528084844.23359-1-hsiangkao@redhat.com
Signed-off-by: Gao Xiang

erofs: convert to use the new mount fs_context api

2020-05-29T10:57:58+00:00

Convert the erofs to use new internal mount API as the old one will
be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Cc: Al Viro 
Cc: David Howells 
Signed-off-by: Chao Yu 
Link: https://lore.kernel.org/r/20200529104836.17843-1-hsiangkao@redhat.com
Signed-off-by: Gao Xiang

erofs: code cleanup by removing ifdef macro surrounding

2020-05-27T08:46:20+00:00

Define erofs_listxattr and erofs_xattr_handlers to NULL when
CONFIG_EROFS_FS_XATTR is not enabled, then we can remove many
ugly ifdef macros in the code.

Signed-off-by: Chengguang Xu 
Reviewed-by: Gao Xiang 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20200526090343.22794-1-cgxu519@mykernel.net
Signed-off-by: Gao Xiang

erofs: handle corrupted images whose decompressed size less than it'd be

2020-03-03T15:40:52+00:00

As Lasse pointed out, "Looking at fs/erofs/decompress.c,
the return value from LZ4_decompress_safe_partial is only
checked for negative value to catch errors. ... So if
I understood it correctly, if there is bad data whose
uncompressed size is much less than it should be, it can
leave part of the output buffer untouched and expose the
previous data as the file content. "

Let's fix it now.

Cc: Lasse Collin 
Fixes: 7fc45dbc938a ("staging: erofs: introduce generic decompression backend")
[ Gao Xiang: v5.3+, I will manually backport this to stable later. ]
Link: https://lore.kernel.org/r/20200226081008.86348-3-gaoxiang25@huawei.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: use LZ4_decompress_safe() for full decoding

2020-03-03T15:40:16+00:00

As Lasse pointed out, "EROFS uses LZ4_decompress_safe_partial
for both partial and full blocks. Thus when it is decoding a
full block, it doesn't know if the LZ4 decoder actually decoded
all the input. The real uncompressed size could be bigger than
the value stored in the file system metadata.

Using LZ4_decompress_safe instead of _safe_partial when
decompressing a full block would help to detect errors."

So it's reasonable to use _safe in case of potential corrupted
images and it might have some speed gain as well although
I didn't observe much difference.

Note that legacy compressor (< 5.3, no LZ4_0PADDING) could
encode extra data in a pcluster, which is excluded as well.

Cc: Lasse Collin 
Fixes: 0ffd71bcc3a0 ("staging: erofs: introduce LZ4 decompression inplace")
[ Gao Xiang: v5.3+, I will manually backport this to stable later. ]
Link: https://lore.kernel.org/r/20200226081008.86348-2-gaoxiang25@huawei.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang