| Message ID | 20230127172834.391311-1-adhemerval.zanella@linaro.org |
|---|---|
| Headers | show |
| Series | Fix opendir regression on some FS | expand |
Am Freitag, 27. Januar 2023, 18:28:29 CET schrieben Sie: > Some filesystem might return a non-representable d_off on getdents > call, even if there are few entries in the directories (for instance > ext4, which returns a hash). This trigger issues with non-LFS readdir [...] Ping- anything still missing here? Thanks :)
Am Freitag, 27. Januar 2023, 18:28:29 CET schrieben Sie: > Some filesystem might return a non-representable d_off on getdents > call, even if there are few entries in the directories (for instance > ext4, which returns a hash). This trigger issues with non-LFS readdir [...] Ping- anything still missing here? Thanks :)
Some filesystem might return a non-representable d_off on getdents call, even if there are few entries in the directories (for instance ext4, which returns a hash). This trigger issues with non-LFS readdir when it finds the first non representable entry, and also for LFS interface when used along with telldir (which return a 'long int', while d_off is potentially off64_t). This patch changes non-LFS readdir so it ignore non representable entries. The opendir now uses getdents64, even for non-LFS and uses a translation buffer to return the getdents entry from the getdents64 buffer. The second part fixes the broken telldir on non LP64 ABIs, where returning d_off as stream position might overflow. For these ABIs, readdir updates an internal list that maps the DIR object off64_t offsets to the returned long int (the function return value). The seekdir will then set the correct offset from the internal list using the telldir as the list key. I have checked on x86_64-linux-gnu, i686-linux-gnu, and arm-linux-gnueabihf. Changes from v4: * Allocate the telldir map an readdir, thus avoid telldir failure. * The translation buffer now uses a fixed size struct. * Fixed the condition to use the long to off64_t map. Changes from v3: * Rebase against master. * Fixed a missing lock unlock on telldir. * Renamed tst-seekdir2 to tst-opendir-nolfs and check the opendir result against getdents64. Adhemerval Zanella (5): linux: Use getdents64 on non-LFS readdir linux: Set internal DIR filepos as off64_t (BZ #23960, BZ #24050) linux: Add __readdir64_unlocked linux: Add __old_readdir64_unlocked linux: Use getdents64 on readdir64 compat implementation dirent/tst-scandir.c | 6 +- dirent/tst-seekdir.c | 8 + include/dirent.h | 3 +- sysdeps/unix/sysv/linux/Makefile | 1 + sysdeps/unix/sysv/linux/alpha/bits/dirent.h | 3 + sysdeps/unix/sysv/linux/bits/dirent.h | 4 + sysdeps/unix/sysv/linux/closedir.c | 4 + sysdeps/unix/sysv/linux/dirstream.h | 22 ++- sysdeps/unix/sysv/linux/getdents64.c | 93 ------------ sysdeps/unix/sysv/linux/olddirent.h | 4 +- sysdeps/unix/sysv/linux/opendir.c | 3 + sysdeps/unix/sysv/linux/readdir.c | 88 ++++++++--- sysdeps/unix/sysv/linux/readdir64.c | 92 ++++++++--- sysdeps/unix/sysv/linux/readdir64_r.c | 159 +++++--------------- sysdeps/unix/sysv/linux/rewinddir.c | 5 + sysdeps/unix/sysv/linux/seekdir.c | 35 ++++- sysdeps/unix/sysv/linux/telldir.c | 35 +++++ sysdeps/unix/sysv/linux/telldir.h | 65 ++++++++ sysdeps/unix/sysv/linux/tst-opendir-nolfs.c | 146 ++++++++++++++++++ 19 files changed, 499 insertions(+), 277 deletions(-) create mode 100644 sysdeps/unix/sysv/linux/telldir.h create mode 100644 sysdeps/unix/sysv/linux/tst-opendir-nolfs.c