The patch titled
coredump: factor out the not-ispipe file checks
has been added to the -mm tree. Its filename is
coredump-factor-out-the-not-ispipe-file-checks.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: coredump: factor out the not-ispipe file checks
From: Oleg Nesterov <oleg@xxxxxxxxxx>
do_coredump() does a lot of file checks after it opens the file or calls
usermode helper. But all of these checks are only needed in !ispipe case.
Move this code into the "else" branch and kill the ugly repetitive ispipe
checks.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Neil Horman <nhorman@xxxxxxxxxxxxx>
Cc: Roland McGrath <roland@xxxxxxxxxx>
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/exec.c | 63 +++++++++++++++++++++++++---------------------------
1 file changed, 31 insertions(+), 32 deletions(-)
diff -puN fs/exec.c~coredump-factor-out-the-not-ispipe-file-checks fs/exec.c
--- a/fs/exec.c~coredump-factor-out-the-not-ispipe-file-checks
+++ a/fs/exec.c
@@ -1834,7 +1834,6 @@ void do_coredump(long signr, int exit_co
char corename[CORENAME_MAX_SIZE + 1];
struct mm_struct *mm = current->mm;
struct linux_binfmt * binfmt;
- struct inode * inode;
const struct cred *old_cred;
struct cred *cred;
int retval = 0;
@@ -1911,9 +1910,6 @@ void do_coredump(long signr, int exit_co
ispipe = format_corename(corename, signr);
unlock_kernel();
- if ((!ispipe) && (cprm.limit < binfmt->min_coredump))
- goto fail_unlock;
-
if (ispipe) {
if (cprm.limit == 1) {
/*
@@ -1966,39 +1962,42 @@ void do_coredump(long signr, int exit_co
corename);
goto fail_dropcount;
}
- } else
+ } else {
+ struct inode *inode;
+
+ if (cprm.limit < binfmt->min_coredump)
+ goto fail_unlock;
+
cprm.file = filp_open(corename,
O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE | flag,
0600);
- if (IS_ERR(cprm.file))
- goto fail_dropcount;
- inode = cprm.file->f_path.dentry->d_inode;
- if (inode->i_nlink > 1)
- goto close_fail; /* multiple links - don't dump */
- if (!ispipe && d_unhashed(cprm.file->f_path.dentry))
- goto close_fail;
-
- /* AK: actually i see no reason to not allow this for named pipes etc.,
- but keep the previous behaviour for now. */
- if (!ispipe && !S_ISREG(inode->i_mode))
- goto close_fail;
- /*
- * Dont allow local users get cute and trick others to coredump
- * into their pre-created files:
- * Note, this is not relevant for pipes
- */
- if (!ispipe && (inode->i_uid != current_fsuid()))
- goto close_fail;
- if (!cprm.file->f_op)
- goto close_fail;
- if (!cprm.file->f_op->write)
- goto close_fail;
- if (!ispipe &&
- do_truncate(cprm.file->f_path.dentry, 0, 0, cprm.file) != 0)
- goto close_fail;
+ if (IS_ERR(cprm.file))
+ goto fail_unlock;
- retval = binfmt->core_dump(&cprm);
+ inode = cprm.file->f_path.dentry->d_inode;
+ if (inode->i_nlink > 1)
+ goto close_fail;
+ if (d_unhashed(cprm.file->f_path.dentry))
+ goto close_fail;
+ /*
+ * AK: actually i see no reason to not allow this for named
+ * pipes etc, but keep the previous behaviour for now.
+ */
+ if (!S_ISREG(inode->i_mode))
+ goto close_fail;
+ /*
+ * Dont allow local users get cute and trick others to coredump
+ * into their pre-created files.
+ */
+ if (inode->i_uid != current_fsuid())
+ goto close_fail;
+ if (!cprm.file->f_op || !cprm.file->f_op->write)
+ goto close_fail;
+ if (do_truncate(cprm.file->f_path.dentry, 0, 0, cprm.file))
+ goto close_fail;
+ }
+ retval = binfmt->core_dump(&cprm);
if (retval)
current->signal->group_exit_code |= 0x80;
close_fail:
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
origin.patch
linux-next.patch
posix-cpu-timers-reset-expire-cache-when-no-timer-is-running.patch
cpu-timers-simplify-rlimit_cpu-handling.patch
cpu-timers-cleanup-arm_timer.patch
cpu-timers-return-correct-previous-timer-reload-value.patch
cpu-timers-change-sigev_none-timer-implementation.patch
cpu-timers-assure-to-not-iterate-over-all-threads-in-fastpath_timer_check.patch
cpu-timers-optimize-run_posix_cpu_timers.patch
proc-cleanup-remove-unused-assignments.patch
kmod-add-init-function-to-usermodehelper.patch
exec-replace-call_usermodehelper_pipe-with-use-of-umh-init-function-and-resolve-limit.patch
umh-creds-convert-call_usermodehelper_keys-to-use-subprocess_info-init.patch
umh-creds-kill-subprocess_info-cred-logic.patch
call_usermodehelper-no-need-to-unblock-signals.patch
wait_for_helper-sigchld-from-user-space-can-lead-to-use-after-free.patch
call_usermodehelper-simplify-fix-umh_no_wait-case.patch
call_usermodehelper-umh_wait_exec-ignores-kernel_thread-failure.patch
coredump-factor-out-the-not-ispipe-file-checks.patch
coredump-cleanup-ispipe-code.patch
coredump-factor-out-put_cred-calls.patch
coredump-shift-down_writemmap_sem-into-coredump_wait.patch
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