From 2507a4fbd48a96bc4236e584252635f8539079df Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 8 Oct 2013 09:11:48 -0400 Subject: [PATCH] make dump_emit() use vfs_write() instead of banging at ->f_op->write directly ... and deal with short writes properly - the output might be to pipe, after all; as it is, e.g. no-MMU case of elf_fdpic coredump can write a whole lot more than a page worth of data at one call. Signed-off-by: Al Viro --- fs/coredump.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/coredump.c b/fs/coredump.c index 319f973..2472ed9 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -696,13 +696,20 @@ EXPORT_SYMBOL(dump_write); int dump_emit(struct coredump_params *cprm, const void *addr, int nr) { struct file *file = cprm->file; - if (dump_interrupted() || !access_ok(VERIFY_READ, addr, nr)) - return 0; + loff_t pos = file->f_pos; + ssize_t n; if (cprm->written + nr > cprm->limit) return 0; - if (file->f_op->write(file, addr, nr, &file->f_pos) != nr) - return 0; - cprm->written += nr; + while (nr) { + if (dump_interrupted()) + return 0; + n = vfs_write(file, addr, nr, &pos); + if (n <= 0) + return 0; + file->f_pos = pos; + cprm->written += n; + nr -= n; + } return 1; } EXPORT_SYMBOL(dump_emit); -- 2.7.4