Avoid remounting already mounted /run and /tmp directories #408
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troglobit
requested changes
Aug 5, 2024
src/util.c
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| struct statfs info; | ||
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| statfs(dir, &info); | ||
| if (info.f_type == TMPFS_MAGIC || info.f_type == OVERLAYFS_SUPER_MAGIC) | ||
| return 1; |
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Either initialize the stack variable with { 0 }, and/or check the return value of statfs(), e.g., on error return 0;
Adds the function fistmpfs to determine if a new tmpfs mount should be performed on /run and /tmp. The function supports cases where more complex mount hierarchies are in use, including overlayfs backed mounts. Signed-off-by: Mathias Thore <[email protected]>
troglobit
approved these changes
Aug 5, 2024
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This is a patch for finit 4.8 beta 1.
It adds the function fistmpfs to determine if a new tmpfs mount should be performed on /run and /tmp. The function supports cases where more complex mount hierarchies are in use, including overlayfs backed mounts.
In our system, /tmp is a symbolic link to a subdirectory in an overlayfs mount. This means that /tmp does not explicitly show up in /proc/mounts, so in fs_finalize, finit decides to mount a new tmpfs on top of it.
This turns out to be problematic for our smallest systems where the new tmpfs on /tmp is not large enough.
I do realize this may be a bit particular to our specific setup, but the patch works on our system. Any comments are welcome.