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| author | Alexey Dobriyan <adobriyan@gmail.com> | 2018-04-11 01:32:11 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-11 19:28:34 +0200 |
| commit | b77d70db659ad3aa662c80cff4475e773a531fbe (patch) | |
| tree | 453429d7d9b3ac146a5a76247a10ed5695e69c8b /fs/proc/generic.c | |
| parent | proc: add selftest for last field of /proc/loadavg (diff) | |
| download | linux-b77d70db659ad3aa662c80cff4475e773a531fbe.tar.xz linux-b77d70db659ad3aa662c80cff4475e773a531fbe.zip | |
proc: reject "." and ".." as filenames
Various subsystems can create files and directories in /proc with names
directly controlled by userspace.
Which means "/", "." and ".." are no-no.
"/" split is already taken care of, do the other 2 prohibited names.
Link: http://lkml.kernel.org/r/20180310001223.GB12443@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/proc/generic.c')
| -rw-r--r-- | fs/proc/generic.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 800247a256c9..5dad2e89007b 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -366,6 +366,14 @@ static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, WARN(1, "name len %u\n", qstr.len); return NULL; } + if (qstr.len == 1 && fn[0] == '.') { + WARN(1, "name '.'\n"); + return NULL; + } + if (qstr.len == 2 && fn[0] == '.' && fn[1] == '.') { + WARN(1, "name '..'\n"); + return NULL; + } if (*parent == &proc_root && name_to_int(&qstr) != ~0U) { WARN(1, "create '/proc/%s' by hand\n", qstr.name); return NULL; |