From fcfe1a5cde0ad12a52f580037da201de667c5ced Mon Sep 17 00:00:00 2001 From: Tobias Stoeckmann Date: Sun, 25 Feb 2018 20:27:59 +0100 Subject: [PATCH] fincore: Handle large files on 32 bit without LFS If util-linux is installed on a system without large file support, an out of memory issue can occur while processing a file which is 2 GB in size: $ ./configure --disable-largefile && make $ dd if=/dev/zero of=2gb-file seek=2147483646 count=1 bs=1 $ fincore 2gb-file (endless loop) fincore: failed to do mmap: 2gb-file: Cannot allocate memory Even though iterating with "len" seems counter-intuitive, it fixes this issue. The variable len is only in the last iteration not a multiplication of pagesize -- which is the requirement for mmap. Signed-off-by: Tobias Stoeckmann --- misc-utils/fincore.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/misc-utils/fincore.c b/misc-utils/fincore.c index ab11594cc..f9534e85b 100644 --- a/misc-utils/fincore.c +++ b/misc-utils/fincore.c @@ -194,12 +194,11 @@ static int fincore_fd (struct fincore_control *ctl, off_t *count_incore) { size_t window_size = N_PAGES_IN_WINDOW * ctl->pagesize; - off_t file_offset; + off_t file_offset, len; int rc = 0; int warned_once = 0; - for (file_offset = 0; file_offset < file_size; file_offset += window_size) { - off_t len; + for (file_offset = 0; file_offset < file_size; file_offset += len) { void *window = NULL; len = file_size - file_offset;