The "umount -f -a -r" get stuck in a endless loop when run with a mountinfo like below: 15 0 179:2 / / ro,relatime - ext4 /dev/root ro 16 15 0:6 / /dev rw,relatime - devtmpfs devtmpfs rw,size=242896k,nr_inodes=60724,mode=755 17 15 0:4 / /proc rw,relatime - proc proc rw 18 15 0:15 / /mnt/.psplash rw,relatime - tmpfs tmpfs rw,size=40k 19 15 0:16 / /sys rw,relatime - sysfs sysfs rw 20 19 0:7 / /sys/kernel/debug rw,relatime - debugfs debugfs rw 21 15 0:17 / /run rw,nosuid,nodev - tmpfs tmpfs rw,mode=755 22 15 0:18 / /var/volatile rw,relatime - tmpfs tmpfs rw 23 15 179:1 / /boot rw,relatime - vfat /dev/mmcblk0p1 rw,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro 24 16 0:19 / /dev/pts rw,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=000 25 18 0:20 / /mnt/.psplash rw,relatime - tmpfs tmpfs rw,size=40k The reason is that the two same mnt entry "/mnt/.psplash" will cause the dst->tab set to NULL when umount this mnt entry the second time. This will trigger an endless loop in mnt_reset_table() because that mnt entry is linked on the libmnt_table but its .tab is set to NULL. Signed-off-by: Kevin Hao <kexin.hao@xxxxxxxxxxxxx> --- libmount/src/fs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libmount/src/fs.c b/libmount/src/fs.c index eb89bb8a39be..4126ee9dce85 100644 --- a/libmount/src/fs.c +++ b/libmount/src/fs.c @@ -188,9 +188,10 @@ struct libmnt_fs *mnt_copy_fs(struct libmnt_fs *dest, dest = mnt_new_fs(); if (!dest) return NULL; + + dest->tab = NULL; } - dest->tab = NULL; dest->id = src->id; dest->parent = src->parent; dest->devno = src->devno; -- 2.14.4
