Hi Thomas :)
On 2023-05-20 06:51, Thomas Weißschuh wrote:
Could you test the fix proposed in
https://github.com/util-linux/util-linux/pull/2248 ?
(For testing on a real system you only need the changes to
libmount/src/hook_mount.c, ignore the testing stuff)
This is addressing the reported
mount --make-slave /proc
issue. I.e. in strace you will see your added call to
mount_setattr_is_supported() which will fail because it is not supported
but afterwards it will try old syscall:
getuid() = 0
geteuid() = 0
open_tree(AT_FDCWD, "/", OPEN_TREE_CLOEXEC) = 3
mount_setattr(-1, NULL, 0, NULL, 0) = -1 ENOSYS (Function not implemented)
getuid() = 0
geteuid() = 0
getgid() = 0
getegid() = 0
prctl(PR_GET_DUMPABLE) = 1 (SUID_DUMP_USER)
newfstatat(AT_FDCWD, "/run/mount/utab", 0x7ffdfabad380, AT_SYMLINK_NOFOLLOW) = -1 ENOENT (No such file or directory)
mkdir("/run/mount", 0755) = -1 EEXIST (File exists)
newfstatat(AT_FDCWD, "/run/mount/utab", 0x7ffdfabad270, 0) = -1 ENOENT (No such file or directory)
newfstatat(AT_FDCWD, "/run/mount", {st_mode=S_IFDIR|0755, st_size=40, ...}, 0) = 0
geteuid() = 0
getegid() = 0
getuid() = 0
getgid() = 0
access("/run/mount", R_OK|W_OK) = 0
mount("none", "/", NULL, MS_SLAVE, NULL) = 0
close(3) = 0
However, I noticed additional problems. Remounts for example are still
not working but no error is shown:
~ # findmnt /
TARGET SOURCE FSTYPE OPTIONS
/ /dev/dm-0 ext4 ro,relatime,stripe=32650
~ # mount -o remount,rw /
~ # findmnt /
TARGET SOURCE FSTYPE OPTIONS
/ /dev/dm-0 ext4 ro,relatime,stripe=32650
I don't see a fallback in strace:
> [...]
open_tree(AT_FDCWD, "/", OPEN_TREE_CLOEXEC) = 3
mount_setattr(-1, NULL, 0, NULL, 0) = -1 ENOSYS (Function not implemented)
getuid() = 0
geteuid() = 0
getgid() = 0
getegid() = 0
prctl(PR_GET_DUMPABLE) = 1 (SUID_DUMP_USER)
newfstatat(AT_FDCWD, "/run/mount/utab", 0x7ffe4fe7c590, AT_SYMLINK_NOFOLLOW) = -1 ENOENT (No such file or directory)
mkdir("/run/mount", 0755) = -1 EEXIST (File exists)
newfstatat(AT_FDCWD, "/run/mount/utab", 0x7ffe4fe7c480, 0) = -1 ENOENT (No such file or directory)
newfstatat(AT_FDCWD, "/run/mount", {st_mode=S_IFDIR|0755, st_size=40, ...}, 0) = 0
geteuid() = 0
getegid() = 0
getuid() = 0
getgid() = 0
access("/run/mount", R_OK|W_OK) = 0
fspick(3, "", FSPICK_NO_AUTOMOUNT|FSPICK_EMPTY_PATH) = 4
fsconfig(4, FSCONFIG_SET_FLAG, "rw", NULL, 0) = 0
fsconfig(4, FSCONFIG_CMD_RECONFIGURE, NULL, NULL, 0) = 0
close(4) = 0
close(3) = 0
dup(1) = 3
close(3) = 0
dup(2) = 3
close(3) = 0
exit_group(0) = ?
+++ exited with 0 +++
--
Regards,
Thomas
