From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org, andi@firstfloor.org,
David Howells <dhowells@redhat.com>,
Neil Horman <nhorman@tuxdriver.com>,
Roland McGrath <roland@redhat.com>
Subject: [PATCH 2/4] coredump: cleanup "ispipe" code
Date: Tue, 16 Mar 2010 20:38:53 +0100 [thread overview]
Message-ID: <20100316193853.GC31632@redhat.com> (raw)
In-Reply-To: <20100316193750.GA31632@redhat.com>
- kill "int dump_count", argv_split(argcp) accepts argcp == NULL.
- move "int dump_count" under " if (ispipe)" branch, fail_dropcount
can check ispipe.
- move "char **helper_argv" as well, change the code to do argv_free()
right after call_usermodehelper_fns().
- If call_usermodehelper_fns() fails goto close_fail label instead
of closing the file by hand.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
fs/exec.c | 39 +++++++++++++++++----------------------
1 file changed, 17 insertions(+), 22 deletions(-)
--- 34-rc1/fs/exec.c~2_IFIFO 2010-03-16 18:06:12.000000000 +0100
+++ 34-rc1/fs/exec.c 2010-03-16 18:09:13.000000000 +0100
@@ -1838,10 +1838,7 @@ void do_coredump(long signr, int exit_co
struct cred *cred;
int retval = 0;
int flag = 0;
- int ispipe = 0;
- char **helper_argv = NULL;
- int helper_argc = 0;
- int dump_count = 0;
+ int ispipe;
static atomic_t core_dump_count = ATOMIC_INIT(0);
struct coredump_params cprm = {
.signr = signr,
@@ -1911,6 +1908,9 @@ void do_coredump(long signr, int exit_co
unlock_kernel();
if (ispipe) {
+ int dump_count;
+ char **helper_argv;
+
if (cprm.limit == 1) {
/*
* Normally core limits are irrelevant to pipes, since
@@ -1932,6 +1932,7 @@ void do_coredump(long signr, int exit_co
printk(KERN_WARNING "Aborting core\n");
goto fail_unlock;
}
+ cprm.limit = RLIM_INFINITY;
dump_count = atomic_inc_return(&core_dump_count);
if (core_pipe_limit && (core_pipe_limit < dump_count)) {
@@ -1941,26 +1942,21 @@ void do_coredump(long signr, int exit_co
goto fail_dropcount;
}
- helper_argv = argv_split(GFP_KERNEL, corename+1, &helper_argc);
+ helper_argv = argv_split(GFP_KERNEL, corename+1, NULL);
if (!helper_argv) {
printk(KERN_WARNING "%s failed to allocate memory\n",
__func__);
goto fail_dropcount;
}
- cprm.limit = RLIM_INFINITY;
-
- /* SIGPIPE can happen, but it's just never processed */
- cprm.file = NULL;
- if (call_usermodehelper_fns(helper_argv[0], helper_argv, NULL,
- UMH_WAIT_EXEC, umh_pipe_setup,
- NULL, &cprm)) {
- if (cprm.file)
- filp_close(cprm.file, NULL);
-
+ retval = call_usermodehelper_fns(helper_argv[0], helper_argv,
+ NULL, UMH_WAIT_EXEC, umh_pipe_setup,
+ NULL, &cprm);
+ argv_free(helper_argv);
+ if (retval) {
printk(KERN_INFO "Core dump to %s pipe failed\n",
corename);
- goto fail_dropcount;
+ goto close_fail;
}
} else {
struct inode *inode;
@@ -2000,17 +1996,16 @@ void do_coredump(long signr, int exit_co
retval = binfmt->core_dump(&cprm);
if (retval)
current->signal->group_exit_code |= 0x80;
-close_fail:
+
if (ispipe && core_pipe_limit)
wait_for_dump_helpers(cprm.file);
- filp_close(cprm.file, NULL);
+close_fail:
+ if (cprm.file)
+ filp_close(cprm.file, NULL);
fail_dropcount:
- if (dump_count)
+ if (ispipe)
atomic_dec(&core_dump_count);
fail_unlock:
- if (helper_argv)
- argv_free(helper_argv);
-
revert_creds(old_cred);
put_cred(cred);
coredump_finish(mm);
next prev parent reply other threads:[~2010-03-16 19:40 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-15 12:29 [PATCH 0/2] exec: refactor how call_usermodehelper works, and update the sense of the core_pipe recursion check (v4 rediff) Neil Horman
2010-03-15 12:33 ` [PATCH 1/2] kmod: add init function to usermodehelper Neil Horman
2010-03-15 17:34 ` Oleg Nesterov
2010-03-15 17:56 ` Neil Horman
2010-03-15 12:36 ` [PATCH 2/2] exec: replace call_usermodehelper_pipe with use of umh init function and resolve limit Neil Horman
2010-03-15 17:39 ` Oleg Nesterov
2010-03-15 19:46 ` [PATCH 0/6] umh: keys, signals, misc Oleg Nesterov
2010-03-15 19:46 ` [PATCH 1/6] umh: creds: convert call_usermodehelper_keys() to use subprocess_info->init() Oleg Nesterov
2010-03-15 19:47 ` [PATCH 2/6] umh: creds: kill subprocess_info->cred logic Oleg Nesterov
2010-03-15 19:47 ` [PATCH 3/6] call_usermodehelper: no need to unblock signals Oleg Nesterov
2010-03-15 19:48 ` [PATCH 4/6] wait_for_helper: SIGCHLD from user-space can lead to use-after-free Oleg Nesterov
2010-03-15 19:48 ` [PATCH 5/6] call_usermodehelper: simplify/fix UMH_NO_WAIT case Oleg Nesterov
2010-03-15 19:49 ` [PATCH 6/6] call_usermodehelper: UMH_WAIT_EXEC ignores kernel_thread() failure Oleg Nesterov
2010-03-16 19:37 ` [PATCH 0/4] do_coredump: cleanups Oleg Nesterov
2010-03-16 19:38 ` [PATCH 1/4] coredump: factor out the not-ispipe file checks Oleg Nesterov
2010-03-16 19:38 ` Oleg Nesterov [this message]
2010-03-16 19:39 ` [PATCH 3/4] coredump: factor out put_cred() calls Oleg Nesterov
2010-03-16 19:39 ` [PATCH 4/4] coredump: shift down_write(mmap_sem) into coredump_wait() Oleg Nesterov
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