shaba/ostree
1
0
Fork 0
mirror of https://github.com/ostreedev/ostree.git synced 2025-03-08 08:58:46 +03:00
Code Issues Projects Releases Wiki Activity

rofiles-fuse: also pass mode for O_RDONLY

Browse Source 
In the `O_RDONLY` case, we were calling `openat` without a mode
argument. However, it's perfectly legal (albeit unusual) to do
`open(O_RDONLY|O_CREAT)`. One such application that makes use of this is
`flock(1)`.

This was actually caught by `_FORTIFY_SOURCE=2`, and once we run
`rofiles-fuse` with `-f`, the message is clear:

```
*** invalid openat64 call: O_CREAT or O_TMPFILE without mode ***:
rofiles-fuse terminated
======= Backtrace: =========
/lib64/libc.so.6(+0x7c8dc)[0x7f36d9f188dc]
/lib64/libc.so.6(__fortify_fail+0x37)[0x7f36d9fbfaa7]
/lib64/libc.so.6(+0x10019a)[0x7f36d9f9c19a]
rofiles-fuse[0x401768]
...
```

Without `_FORTIFY_SOURCE`, the file gets created, but its mode is
completely random.

I ran into this while investigating
https://github.com/projectatomic/rpm-ostree/pull/1003.

Closes: #1200
Approved by: cgwalters
This commit is contained in:
Jonathan Lebon 2017-09-20 18:38:16 +00:00 committed by Atomic Bot
parent 3f8f878fa3
commit d4c7093e37
2 changed files with 5 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/rofiles-fuse/main.c
View File

@ -313,7 +313,7 @@ do_open (const char *path, mode_t mode, struct fuse_file_info *finfo)
if ((finfo->flags & O_ACCMODE) == O_RDONLY)
{
/* Read */
fd = openat (basefd, path, finfo->flags);
fd = openat (basefd, path, finfo->flags, mode);
if (fd == -1)
return -errno;
}

5
tests/test-rofiles-fuse.sh
View File

@ -26,7 +26,7 @@ skip_without_user_xattrs
setup_test_repository "bare"
echo "1..7"
echo "1..8"
cd ${test_tmpdir}
mkdir mnt
@ -114,3 +114,6 @@ fi
assert_file_has_content err.txt "Unable to do hardlink checkout across devices"
echo "ok checkout copy fallback"
# check that O_RDONLY|O_CREAT is handled correctly; used by flock(1) at least
flock mnt/nonexistent-file echo "ok create file in ro mode"