diff options
| author | Denys Vlasenko <vda.linux@googlemail.com> | 2019-04-29 17:59:08 +0200 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2019-04-29 17:59:08 +0200 |
| commit | f3a064f4956e113978e74486300dcd1e3e044efa (patch) | |
| tree | 1a122c33fd15dce4563cd70e3c3e2c852578986b | |
| parent | fa8878bf1fe331df752395cce90da212e25e07b7 (diff) | |
libbbb: find_mount_point() too eager to stat mounted devices
None of the below "devices" (first word on the line) are real.
sysfs /sys sysfs rw,nosuid,nodev,noexec,relatime 0 0
proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0
devtmpfs /dev devtmpfs rw,nosuid,size=7917900k,nr_inodes=1979475,mode=755 0 0
tmpfs /dev/shm tmpfs rw,nosuid,nodev 0 0
devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000 0 0
tmpfs /run tmpfs rw,nosuid,nodev,mode=755 0 0
pstore /sys/fs/pstore pstore rw,nosuid,nodev,noexec,relatime 0 0
configfs /sys/kernel/config configfs rw,relatime 0 0
tmpfs /tmp tmpfs rw,relatime 0 0
function old new delta
find_mount_point 297 302 +5
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
| -rw-r--r-- | libbb/find_mount_point.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/libbb/find_mount_point.c b/libbb/find_mount_point.c index 94bbf1d4a..0e1be3820 100644 --- a/libbb/find_mount_point.c +++ b/libbb/find_mount_point.c @@ -56,11 +56,22 @@ struct mntent* FAST_FUNC find_mount_point(const char *name, int subdir_too) continue; /* Is device's dev_t == name's dev_t? */ - if (stat(mountEntry->mnt_fsname, &s) == 0 && s.st_rdev == devno_of_name) + if (mountEntry->mnt_fsname[0] == '/' + /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + * avoid stat'ing "sysfs", "proc", "none" and such, + * useless at best, can stat unrelated files at worst. + */ + && stat(mountEntry->mnt_fsname, &s) == 0 + && s.st_rdev == devno_of_name + ) { break; + } /* Match the directory's mount point. */ - if (stat(mountEntry->mnt_dir, &s) == 0 && s.st_dev == devno_of_name) + if (stat(mountEntry->mnt_dir, &s) == 0 + && s.st_dev == devno_of_name + ) { break; + } } endmntent(mtab_fp); |