Merge tag 'v3.10.90' into update

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / coredump.c

diff --git a/fs/coredump.c b/fs/coredump.c
index 4f03b2b503756a03338e21f92e74b1fb84784c62..81c862591ca1da42885fab5f686fcad531c3c9e2 100644 (file)
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -512,14 +512,23 @@ void do_coredump(siginfo_t *siginfo)
        audit_core_dumps(siginfo->si_signo);
 
        binfmt = mm->binfmt;
-       if (!binfmt || !binfmt->core_dump)
+       if (!binfmt || !binfmt->core_dump) {
+               printk(KERN_WARNING "Skip process %d(%s) core dump(!binfmt?%s)\n",
+                       task_tgid_vnr(current), current->comm, (!binfmt) ? "yes":"no");
                goto fail;
-       if (!__get_dumpable(cprm.mm_flags))
+       }
+       if (!__get_dumpable(cprm.mm_flags)) {
+               printk(KERN_WARNING "Skip process %d(%s) core dump(mm_flags:%x)\n",
+                       task_tgid_vnr(current), current->comm, (unsigned int)cprm.mm_flags);
                goto fail;
+       }
 
        cred = prepare_creds();
-       if (!cred)
+       if (!cred) {
+               printk(KERN_WARNING "Skip process %d(%s) core dump(prepare_creds failed)\n",
+                       task_tgid_vnr(current), current->comm);
                goto fail;
+       }
        /*
         * We cannot trust fsuid as being the "true" uid of the process
         * nor do we know its entire history. We only know it was tainted
@@ -682,9 +691,12 @@ void do_coredump(siginfo_t *siginfo)
                put_files_struct(displaced);
        if (!dump_interrupted()) {
                file_start_write(cprm.file);
+               printk(KERN_WARNING "before %d core dump\n", current->pid);
                core_dumped = binfmt->core_dump(&cprm);
                file_end_write(cprm.file);
        }
+       else
+               printk(KERN_WARNING "before %d core dump interrupted error\n", current->pid);
        if (ispipe && core_pipe_limit)
                wait_for_dump_helpers(cprm.file);
 close_fail:
@@ -711,9 +723,26 @@ fail:
  */
 int dump_write(struct file *file, const void *addr, int nr)
 {
-       return !dump_interrupted() &&
-               access_ok(VERIFY_READ, addr, nr) &&
-               file->f_op->write(file, addr, nr, &file->f_pos) == nr;
+       if (!dump_interrupted()) {
+               if (access_ok(VERIFY_READ, addr, nr)) {
+                       int pipe_ret = file->f_op->write(file, addr, nr, &file->f_pos);
+                       if (pipe_ret == nr) {
+                               return 1;
+                       }
+                       if (pipe_ret == -ERESTARTSYS) {
+                       }
+                       else {
+                               printk(KERN_WARNING "coredump(%d): pipe dump write error nr:%d, ret:%d\n", current->pid, nr, pipe_ret);
+                       }
+               }
+               else {
+                       printk(KERN_WARNING "coredump(%d): access verify error\n", current->pid);
+               }
+       }
+       else {
+               printk(KERN_WARNING "coredump(%d): interrupted error\n", current->pid);
+       }
+       return 0;
 }
 EXPORT_SYMBOL(dump_write);