prueba con chmod 777 nombre_carpeta y si quieres que lo haga efectivo al resto pon -R (recursivo)
Puede que también te de guerra con propietario y grupo, usa el comando Chown
Chown -R propietario.grupo nombre_carpeta
Pero sobre todo usa la ayuda
$ man chmod
CHMOD(1) BSD General Commands Manual CHMOD(1)
NAME
chmod -- change file modes or Access Control Lists
SYNOPSIS
chmod [-fv] [-R [-H | -L | -P]] mode file ...
chmod [-fv] [-R [-H | -L | -P]] [-a | +a | =a] ACE file ...
chmod [-fv] [-R [-H | -L | -P]] [-E] file ...
chmod [-fv] [-R [-H | -L | -P]] [-C] file ...
DESCRIPTION
The chmod utility modifies the file mode bits of the listed files as
specified by the mode operand. It may also be used to modify the Access
Control Lists (ACLs) associated with the listed files.
The generic options are as follows:
-H If the -R option is specified, symbolic links on the command line
are followed. (Symbolic links encountered in the tree traversal
are not followed by default.)
-L If the -R option is specified, all symbolic links are followed.
-P If the -R option is specified, no symbolic links are followed.
This is the default.
-R Change the modes of the file hierarchies rooted in the files
instead of just the files themselves.
-f Do not display a diagnostic message if chmod could not modify the
mode for file.
-v Cause chmod to be verbose, showing filenames as the mode is modi-
fied. If the -v flag is specified more than once, the old and
new modes of the file will also be printed, in both octal and
The -H, -L and -P options are ignored unless the -R option is specified.
In addition, these options override each other and the command's actions
are determined by the last one specified.
Only the owner of a file or the super-user is permitted to change the
mode of a file.
DIAGNOSTICS
The chmod utility exits 0 on success, and >0 if an error occurs.
MODES
Modes may be absolute or symbolic. An absolute mode is an octal number
constructed from the sum of one or more of the following values:
4000 (the set-user-ID-on-execution bit) Executable files with
this bit set will run with effective uid set to the uid of
the file owner. Directories with the set-user-id bit set
will force all files and sub-directories created in them to
be owned by the directory owner and not by the uid of the
creating process, if the underlying file system supports
this feature: see chmod(2) and the suiddir option to
mount(8).
2000 (the set-group-ID-on-execution bit) Executable files with
this bit set will run with effective gid set to the gid of
the file owner.
1000 (the sticky bit) See chmod(2) and sticky(8).
0400 Allow read by owner.
0200 Allow write by owner.
0100 For files, allow execution by owner. For directories,
allow the owner to search in the directory.
0040 Allow read by group members.
0020 Allow write by group members.
0010 For files, allow execution by group members. For directo-
ries, allow group members to search in the directory.
0004 Allow read by others.
0002 Allow write by others.
0001 For files, allow execution by others. For directories
allow others to search in the directory.
For example, the absolute mode that permits read, write and execute by
the owner, read and execute by group members, read and execute by others,
and no set-uid or set-gid behaviour is 755 (400+200+100+040+010+004+001).
The symbolic mode is described by the following grammar:
mode ::= clause [, clause ...]
clause ::= [who ...] [action ...] action
action ::= op [perm ...]
who ::= a | u | g | o
op ::= + | - | =
perm ::= r | s | t | w | x | X | u | g | o
The who symbols ``u'', ``g'', and ``o'' specify the user, group, and
other parts of the mode bits, respectively. The who symbol ``a'' is
equivalent to ``ugo''.
The perm symbols represent the portions of the mode bits as follows:
r The read bits.
s The set-user-ID-on-execution and set-group-ID-on-execution
bits.
t The sticky bit.
w The write bits.
x The execute/search bits.
X The execute/search bits if the file is a directory or any
of the execute/search bits are set in the original (unmodi-
fied) mode. Operations with the perm symbol ``X'' are only
meaningful in conjunction with the op symbol ``+'', and are
ignored in all other cases.
u The user permission bits in the original mode of the file.
etc etc
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