From: Christoph Hellwig <hch@lst.de>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>, Brian Gerst <brgerst@gmail.com>,
Luis Chamberlain <mcgrof@kernel.org>,
linux-arm-kernel@lists.infradead.org, x86@kernel.org,
linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org,
linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 4/5] exec: split prepare_arg_pages
Date: Sat, 27 Jun 2020 09:27:03 +0200 [thread overview]
Message-ID: <20200627072704.2447163-5-hch@lst.de> (raw)
In-Reply-To: <20200627072704.2447163-1-hch@lst.de>
Move counting the arguments and enviroment variables out of
prepare_arg_pages and rename the rest of the function to check_arg_limit.
This prepares for a version of do_execvat that takes kernel pointers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/exec.c | 26 ++++++++++++++------------
1 file changed, 14 insertions(+), 12 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index a5d91f8b1341d5..34781db6bf6889 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -435,20 +435,10 @@ static int count_strings(const char __user *const __user *argv)
return i;
}
-static int prepare_arg_pages(struct linux_binprm *bprm,
- const char __user *const __user *argv,
- const char __user *const __user *envp)
+static int check_arg_limit(struct linux_binprm *bprm)
{
unsigned long limit, ptr_size;
- bprm->argc = count_strings(argv);
- if (bprm->argc < 0)
- return bprm->argc;
-
- bprm->envc = count_strings(envp);
- if (bprm->envc < 0)
- return bprm->envc;
-
/*
* Limit to 1/4 of the max stack size or 3/4 of _STK_LIM
* (whichever is smaller) for the argv+env strings.
@@ -1886,7 +1876,19 @@ int do_execveat(int fd, struct filename *filename,
if (retval)
goto out_unmark;
- retval = prepare_arg_pages(bprm, argv, envp);
+ bprm->argc = count_strings(argv);
+ if (bprm->argc < 0) {
+ retval = bprm->argc;
+ goto out;
+ }
+
+ bprm->envc = count_strings(envp);
+ if (bprm->envc < 0) {
+ retval = bprm->envc;
+ goto out;
+ }
+
+ retval = check_arg_limit(bprm);
if (retval < 0)
goto out;
--
2.26.2
next prev parent reply other threads:[~2020-06-27 7:27 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-27 7:26 properly support exec with kernel pointers v3 Christoph Hellwig
2020-06-27 7:26 ` Christoph Hellwig
2020-06-27 7:27 ` [PATCH 1/5] exec: cleanup the execve wrappers Christoph Hellwig
2020-06-27 7:27 ` Christoph Hellwig
2020-06-27 7:27 ` [PATCH 2/5] exec: simplify the compat syscall handling Christoph Hellwig
2020-06-27 7:27 ` Christoph Hellwig
2020-06-27 7:27 ` [PATCH 3/5] exec: cleanup the count() function Christoph Hellwig
2020-06-27 7:27 ` Christoph Hellwig
2020-06-27 7:27 ` Christoph Hellwig [this message]
2020-06-27 7:27 ` [PATCH 4/5] exec: split prepare_arg_pages Christoph Hellwig
2020-06-27 7:27 ` [PATCH 5/5] exec: add a kernel_execveat helper Christoph Hellwig
2020-06-27 7:27 ` Christoph Hellwig
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