diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-03 10:33:36 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-05 13:54:15 +0100 |
| commit | b8b0e9650eeb6637b4e1cf3d6aaf0e96f87862e7 (patch) | |
| tree | e13bf9143996003e7e8c724535439b8385fbaf04 /fs | |
| parent | cf3998254f02b60234dcedef6b2979e7208b3f58 (diff) | |
Revert "exec: don't WARN for racy path_noexec check"
This reverts commit d62ba2a5536df83473a2ac15ab302258e3845251 which is
commit 0d196e7589cefe207d5d41f37a0a28a1fdeeb7c6 upstream.
A later commit needs to be reverted so revert this one as well to allow
that to happen properly.
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/exec.c | 31 |
1 files changed, 19 insertions, 12 deletions
diff --git a/fs/exec.c b/fs/exec.c index dad402d55681..00c968a739c3 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -145,11 +145,13 @@ SYSCALL_DEFINE1(uselib, const char __user *, library) goto out; /* - * Check do_open_execat() for an explanation. + * may_open() has already checked for this, so it should be + * impossible to trip now. But we need to be extra cautious + * and check again at the very end too. */ error = -EACCES; - if (WARN_ON_ONCE(!S_ISREG(file_inode(file)->i_mode)) || - path_noexec(&file->f_path)) + if (WARN_ON_ONCE(!S_ISREG(file_inode(file)->i_mode) || + path_noexec(&file->f_path))) goto exit; error = -ENOEXEC; @@ -953,6 +955,7 @@ EXPORT_SYMBOL(transfer_args_to_stack); static struct file *do_open_execat(int fd, struct filename *name, int flags) { struct file *file; + int err; struct open_flags open_exec_flags = { .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, .acc_mode = MAY_EXEC, @@ -969,20 +972,24 @@ static struct file *do_open_execat(int fd, struct filename *name, int flags) file = do_filp_open(fd, name, &open_exec_flags); if (IS_ERR(file)) - return file; + goto out; /* - * In the past the regular type check was here. It moved to may_open() in - * 633fb6ac3980 ("exec: move S_ISREG() check earlier"). Since then it is - * an invariant that all non-regular files error out before we get here. + * may_open() has already checked for this, so it should be + * impossible to trip now. But we need to be extra cautious + * and check again at the very end too. */ - if (WARN_ON_ONCE(!S_ISREG(file_inode(file)->i_mode)) || - path_noexec(&file->f_path)) { - fput(file); - return ERR_PTR(-EACCES); - } + err = -EACCES; + if (WARN_ON_ONCE(!S_ISREG(file_inode(file)->i_mode) || + path_noexec(&file->f_path))) + goto exit; +out: return file; + +exit: + fput(file); + return ERR_PTR(err); } /** |