* [PATCH 2/2] fincore: Handle large files on 32 bit without LFS
@ 2018-02-25 19:27 Tobias Stoeckmann
2018-02-26 10:56 ` Karel Zak
0 siblings, 1 reply; 2+ messages in thread
From: Tobias Stoeckmann @ 2018-02-25 19:27 UTC (permalink / raw)
To: util-linux
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 <tobias@stoeckmann.org>
---
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;
--
2.16.2
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH 2/2] fincore: Handle large files on 32 bit without LFS
2018-02-25 19:27 [PATCH 2/2] fincore: Handle large files on 32 bit without LFS Tobias Stoeckmann
@ 2018-02-26 10:56 ` Karel Zak
0 siblings, 0 replies; 2+ messages in thread
From: Karel Zak @ 2018-02-26 10:56 UTC (permalink / raw)
To: Tobias Stoeckmann; +Cc: util-linux
On Sun, Feb 25, 2018 at 08:27:59PM +0100, Tobias Stoeckmann wrote:
> misc-utils/fincore.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
Applied, thanks.
--
Karel Zak <kzak@redhat.com>
http://karelzak.blogspot.com
^ permalink raw reply [flat|nested] 2+ messages in thread
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