diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2017-10-04 01:15:58 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-10-04 02:54:25 +0200 |
| commit | 50097f74934e3ec8fb1e6f3087568b958972817d (patch) | |
| tree | 686cdcc7ec9506b3a9175903a12e9354f376bd5e /fs/binfmt_misc.c | |
| parent | exec: binfmt_misc: fix race between load_misc_binary() and kill_node() (diff) | |
| download | linux-50097f74934e3ec8fb1e6f3087568b958972817d.tar.xz linux-50097f74934e3ec8fb1e6f3087568b958972817d.zip | |
exec: binfmt_misc: kill the onstack iname[BINPRM_BUF_SIZE] array
After the previous change "fmt" can't go away, we can kill
iname/iname_addr and use fmt->interpreter.
Link: http://lkml.kernel.org/r/20170922143653.GA17232@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ben Woodard <woodard@redhat.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jim Foraker <foraker1@llnl.gov>
Cc: <tdhooge@llnl.gov>
Cc: Travis Gummels <tgummels@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/binfmt_misc.c')
| -rw-r--r-- | fs/binfmt_misc.c | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c index f5f8c2541790..2a46762def31 100644 --- a/fs/binfmt_misc.c +++ b/fs/binfmt_misc.c @@ -54,7 +54,7 @@ typedef struct { int size; /* size of magic/mask */ char *magic; /* magic or filename extension */ char *mask; /* mask, NULL for exact match */ - char *interpreter; /* filename of interpreter */ + const char *interpreter; /* filename of interpreter */ char *name; struct dentry *dentry; struct file *interp_file; @@ -131,8 +131,6 @@ static int load_misc_binary(struct linux_binprm *bprm) { Node *fmt; struct file *interp_file = NULL; - char iname[BINPRM_BUF_SIZE]; - const char *iname_addr = iname; int retval; int fd_binary = -1; @@ -143,10 +141,8 @@ static int load_misc_binary(struct linux_binprm *bprm) /* to keep locking time low, we copy the interpreter string */ read_lock(&entries_lock); fmt = check_file(bprm); - if (fmt) { + if (fmt) dget(fmt->dentry); - strlcpy(iname, fmt->interpreter, BINPRM_BUF_SIZE); - } read_unlock(&entries_lock); if (!fmt) return retval; @@ -198,13 +194,13 @@ static int load_misc_binary(struct linux_binprm *bprm) bprm->argc++; /* add the interp as argv[0] */ - retval = copy_strings_kernel(1, &iname_addr, bprm); + retval = copy_strings_kernel(1, &fmt->interpreter, bprm); if (retval < 0) goto error; bprm->argc++; /* Update interp in case binfmt_script needs it. */ - retval = bprm_change_interp(iname, bprm); + retval = bprm_change_interp(fmt->interpreter, bprm); if (retval < 0) goto error; @@ -213,7 +209,7 @@ static int load_misc_binary(struct linux_binprm *bprm) if (!IS_ERR(interp_file)) deny_write_access(interp_file); } else { - interp_file = open_exec(iname); + interp_file = open_exec(fmt->interpreter); } retval = PTR_ERR(interp_file); if (IS_ERR(interp_file)) |