diff options
| author | Aleksandr Nogikh <nogikh@google.com> | 2024-04-10 17:16:55 +0200 |
|---|---|---|
| committer | Aleksandr Nogikh <nogikh@google.com> | 2024-04-10 16:06:33 +0000 |
| commit | 33b9e058838dbe993f943107bcdd0223e831bd84 (patch) | |
| tree | 1e59a020dd3791e1b9f53fbd74bc8280c73b6f9e /executor/common_linux.h | |
| parent | 5b968ccf1481a8bae7fce49cca01cf3597da4be8 (diff) | |
executor: cleanup mounts with MNT_FORCE
Starting from v6.9, we can no longer reuse a loop device while some
filesystem is mounted on it. It conflicts with the MNT_DETACH approach
we were previously using.
Let's umount synchronously instead, but also with a MNT_FORCE flag to
abort potentially long graceful cleanup operations. We don't need them
for the filesystems mounted only for fuzzing purposes.
Diffstat (limited to 'executor/common_linux.h')
| -rw-r--r-- | executor/common_linux.h | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/executor/common_linux.h b/executor/common_linux.h index eea0fd2cf..e83bad6c0 100644 --- a/executor/common_linux.h +++ b/executor/common_linux.h @@ -4534,10 +4534,15 @@ static void remove_dir(const char* dir) DIR* dp = 0; retry: #if SYZ_EXECUTOR || !SYZ_SANDBOX_ANDROID + // Starting from v6.9, it does no longer make sense to use MNT_DETACH, because + // a loop device may only be reused in RW mode if no mounted filesystem keeps a + // reference to it. So we have to umount them synchronously. + // MNT_FORCE should hopefully prevent hangs for filesystems that may require a complex cleanup. + const int umount_flags = MNT_FORCE | UMOUNT_NOFOLLOW; #if SYZ_EXECUTOR if (!flag_sandbox_android) #endif - while (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) { + while (umount2(dir, umount_flags) == 0) { debug("umount(%s)\n", dir); } #endif @@ -4563,7 +4568,7 @@ retry: #if SYZ_EXECUTOR if (!flag_sandbox_android) #endif - while (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) { + while (umount2(filename, umount_flags) == 0) { debug("umount(%s)\n", filename); } #endif @@ -4601,7 +4606,7 @@ retry: if (!flag_sandbox_android) { #endif debug("umount(%s)\n", filename); - if (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW)) + if (umount2(filename, umount_flags)) exitf("umount(%s) failed", filename); #if SYZ_EXECUTOR } @@ -4636,7 +4641,7 @@ retry: if (!flag_sandbox_android) { #endif debug("umount(%s)\n", dir); - if (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW)) + if (umount2(dir, umount_flags)) exitf("umount(%s) failed", dir); #if SYZ_EXECUTOR } |