util-linux/SOURCES/0023-libblkid-fix-file-descriptor-leak-in-blkid_verify.patch
2021-10-08 17:29:53 +00:00

88 lines
3.0 KiB
Diff

From e431bfeca0f3e7be2eba30be83260f20976f871d Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Wed, 31 Jul 2019 16:18:27 +0200
Subject: [PATCH 23/24] libblkid: fix file descriptor leak in blkid_verify()
The function blkid_verify() uses private device file descriptor and
uses blkid_probe_set_device() to assign the descriptor to low-level
probing code. Unfortunately, close() in this case is not enough as the
prober can internally open whole-disk device too.
The library API has been extended so blkid_probe_set_device()
deallocates and close previously used prober for whole-disk. This new
functionality is used in blkid_verify() now.
Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1734553
Upstream: http://github.com/karelzak/util-linux/commit/c4d6d1c54dcd0eff701236d396d88b1fc6251768
Signed-off-by: Karel Zak <kzak@redhat.com>
---
libblkid/src/probe.c | 19 ++++++++++++++++---
libblkid/src/verify.c | 4 +++-
2 files changed, 19 insertions(+), 4 deletions(-)
diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
index 647ae416a..a6dc8416a 100644
--- a/libblkid/src/probe.c
+++ b/libblkid/src/probe.c
@@ -848,10 +848,15 @@ failed:
* @off: begin of probing area
* @size: size of probing area (zero means whole device/file)
*
- * Assigns the device to probe control struct, resets internal buffers and
- * resets the current probing.
+ * Assigns the device to probe control struct, resets internal buffers, resets
+ * the current probing, and close previously associated device (if open by
+ * libblkid).
*
- * Returns: -1 in case of failure, or 0 on success.
+ * If @fd is < 0 than only resets the prober and returns 1. Note that
+ * blkid_reset_probe() keeps the device associated with the prober, but
+ * blkid_probe_set_device() does complete reset.
+ *
+ * Returns: -1 in case of failure, 0 on success and 1 on reset.
*/
int blkid_probe_set_device(blkid_probe pr, int fd,
blkid_loff_t off, blkid_loff_t size)
@@ -866,6 +871,11 @@ int blkid_probe_set_device(blkid_probe pr, int fd,
if ((pr->flags & BLKID_FL_PRIVATE_FD) && pr->fd >= 0)
close(pr->fd);
+ if (pr->disk_probe) {
+ blkid_free_probe(pr->disk_probe);
+ pr->disk_probe = NULL;
+ }
+
pr->flags &= ~BLKID_FL_PRIVATE_FD;
pr->flags &= ~BLKID_FL_TINY_DEV;
pr->flags &= ~BLKID_FL_CDROM_DEV;
@@ -881,6 +891,9 @@ int blkid_probe_set_device(blkid_probe pr, int fd,
pr->wipe_size = 0;
pr->wipe_chain = NULL;
+ if (fd < 0)
+ return 1;
+
#if defined(POSIX_FADV_RANDOM) && defined(HAVE_POSIX_FADVISE)
/* Disable read-ahead */
posix_fadvise(fd, 0, 0, POSIX_FADV_RANDOM);
diff --git a/libblkid/src/verify.c b/libblkid/src/verify.c
index 7f44f5497..750378f8c 100644
--- a/libblkid/src/verify.c
+++ b/libblkid/src/verify.c
@@ -184,9 +184,11 @@ blkid_dev blkid_verify(blkid_cache cache, blkid_dev dev)
dev->bid_name, (long long)st.st_rdev, dev->bid_type));
}
- blkid_reset_probe(cache->probe);
+ /* reset prober */
blkid_probe_reset_superblocks_filter(cache->probe);
+ blkid_probe_set_device(cache->probe, -1, 0, 0);
close(fd);
+
return dev;
}
--
2.21.0