5.10-stable review patch. If anyone has any objections, please let me know.
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From: Eric W. Biederman ebiederm@xmission.com
[ Upstream commit 878f12dbb8f514799d126544d59be4d2675caac3 ]
Al Viro pointed out that using the phrase "close_on_exec(fd, rcu_dereference_raw(current->files->fdt))" instead of wrapping it in rcu_read_lock(), rcu_read_unlock() is a very questionable optimization[1].
Once wrapped with rcu_read_lock()/rcu_read_unlock() that phrase becomes equivalent the helper function get_close_on_exec so simplify the code and make it more robust by simply using get_close_on_exec.
[1] https://lkml.kernel.org/r/20201207222214.GA4115853@ZenIV.linux.org.uk Suggested-by: Al Viro viro@ftp.linux.org.uk Link: https://lkml.kernel.org/r/87k0tqr6zi.fsf_-_@x220.int.ebiederm.org Signed-off-by: Eric W. Biederman ebiederm@xmission.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/exec.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c index ebe9011955b9b..fb8813cc532d0 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1821,8 +1821,7 @@ static int bprm_execve(struct linux_binprm *bprm, * inaccessible after exec. Relies on having exclusive access to * current->files (due to unshare_files above). */ - if (bprm->fdpath && - close_on_exec(fd, rcu_dereference_raw(current->files->fdt))) + if (bprm->fdpath && get_close_on_exec(fd)) bprm->interp_flags |= BINPRM_FLAGS_PATH_INACCESSIBLE;
/* Set the unchanging part of bprm->cred */