diff options
| author | Heinrich Schuchardt <xypron.glpk@gmx.de> | 2018-07-02 02:41:23 +0200 |
|---|---|---|
| committer | Alexander Graf <agraf@suse.de> | 2018-07-25 14:59:44 +0200 |
| commit | 0dc1bfb7302d220a48364263d5632d6d572b069b (patch) | |
| tree | f300fb9a8dcd6c034735ab1b5e8d6d7768656c2f /fs | |
| parent | 1fcb7ea28400aa69e157dc4b19c9667e96d3a033 (diff) | |
fs: fat: cannot write to subdirectories
fs_fat_write() is not able to write to subdirectories.
Currently if a filepath with a leading slash is passed, the slash is
treated as part of the filename to be created in the root directory.
Strip leading (back-)slashes.
Check that the remaining filename does not contain any illegal characters
(<>:"/\|?*). This way we will throw an error when trying to write to a
subdirectory.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/fat/fat_write.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index 3b77557b3e..27e0ff6696 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -909,9 +909,11 @@ static int do_fat_write(const char *filename, void *buffer, loff_t size, volume_info volinfo; fsdata datablock; fsdata *mydata = &datablock; - int cursect; + int cursect, i; int ret = -1, name_len; char l_filename[VFAT_MAXLEN_BYTES]; + char bad[2] = " "; + const char illegal[] = "<>:\"/\\|?*"; *actwrite = size; dir_curclust = 0; @@ -971,6 +973,18 @@ static int do_fat_write(const char *filename, void *buffer, loff_t size, } dentptr = (dir_entry *) do_fat_read_at_block; + /* Strip leading (back-)slashes */ + while ISDIRDELIM(*filename) + ++filename; + /* Check that the filename is valid */ + for (i = 0; i < strlen(illegal); ++i) { + *bad = illegal[i]; + if (strstr(filename, bad)) { + printf("FAT: illegal filename (%s)\n", filename); + return -1; + } + } + name_len = strlen(filename); if (name_len >= VFAT_MAXLEN_BYTES) name_len = VFAT_MAXLEN_BYTES - 1; |