Lintian tag: binary-file-built-without-LFS-support

Type: information

Description (from lintian-explain-tags)

The listed ELF binary appears to be (partially) built without "Large File
Support" (LFS). If so, it may not be able to handle large files or files
with large metadata values, such as inode numbers, correctly.

To support large files, code review might be needed to make sure that
those files are not slurped into memory or mmap(2)ed, and that correct
64-bit data types are used (ex: off_t instead of ssize_t), etc. Once that
has been done ensure _FILE_OFFSET_BITS is defined and set to 64 before any
system headers are included (note that on systems were the ABI has LFS
enabled by default, setting _FILE_OFFSET_BITS to 64 will be a no-op, and
as such optional). This can be done by using the AC_SYS_LARGEFILE macro
with autoconf which will set any macro required to enable LFS when
necessary, or by enabling the lfs feature from the future dpkg-buildflags
feature area which sets the CPPFLAGS variable (since dpkg-dev 1.19.0).
Note though, that getconf LFS_CFLAGS must not be used, as it does not
support cross-building. Using _FILE_OFFSET_BITS should require no system
function renames (eg. from open(2) to open64(2)), and if this tag is still
emitted, the most probable cause is because the macro is not seen by the
system code being compiled.

Take into account that even if this tag is not emitted, that does not mean
the binary is LFS-safe (ie. no OOM conditions, file truncation or
overwrite will happen).

Also note that enabling LFS on a shared library is not always safe as it
might break ABI in case some of the exported types change size, in those
cases a SOVERSION bump might be required. Or alternatively, on systems
with an ABI without LFS, defining _LARGEFILE64_SOURCE and exporting both
32 and 64-bit variants of the interfaces can avoid the SOVERSION bump, at
the cost of more complex maintenance.

Please refer to http://www.unix.org/version2/whatsnew/lfs20mar.html and
https://www.gnu.org/software/libc/manual/html_node/Feature-Test-Macros.html
for details.

Visibility: info
Show-Always: no
Check: binaries/large-file-support
This tag is experimental.

Affected packages

Output limited to the first 5000 results.