From 8125a64ff9e98d09c659dbd5adbca521d63a268b Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Thu, 7 Jul 2016 14:22:41 +0200 Subject: [PATCH 86/86] libblkid: avoid recursion in EBR Upstream: http://github.com/karelzak/util-linux/commit/7164a1c34d18831ac61c6744ad14ce916d389b3f Upstream: http://github.com/karelzak/util-linux/commit/50d1594c2e6142a3b51d2143c74027480df082e0 Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1349536 Signed-off-by: Karel Zak --- libblkid/src/partitions/dos.c | 21 +++++++++++++++++++-- libblkid/src/partitions/partitions.c | 14 ++++++++++++++ libblkid/src/partitions/partitions.h | 2 ++ 3 files changed, 35 insertions(+), 2 deletions(-) diff --git a/libblkid/src/partitions/dos.c b/libblkid/src/partitions/dos.c index 2d4a537..563fe9a 100644 --- a/libblkid/src/partitions/dos.c +++ b/libblkid/src/partitions/dos.c @@ -48,6 +48,12 @@ static int parse_dos_extended(blkid_probe pr, blkid_parttable tab, int ct_nodata = 0; /* count ext.partitions without data partitions */ int i; + DBG(LOWPROBE, blkid_debug("parse EBR [start=%d, size=%d]", ex_start/ssf, ex_size/ssf)); + if (ex_start == 0) { + DBG(LOWPROBE, blkid_debug("Bad offset in primary extended partition -- ignore")); + return 0; + } + while (1) { struct dos_partition *p, *p0; uint32_t start, size; @@ -100,6 +106,13 @@ static int parse_dos_extended(blkid_probe pr, blkid_parttable tab, continue; } + /* Avoid recursive non-empty links, see ct_nodata counter */ + if (blkid_partlist_get_partition_by_start(ls, abs_start)) { + DBG(LOWPROBE, blkid_debug("#%d: EBR duplicate data partition [abs start=%u] -- ignore", + i + 1, abs_start)); + continue; + } + par = blkid_partlist_add_partition(ls, tab, abs_start, size); if (!par) return -ENOMEM; @@ -116,8 +129,12 @@ static int parse_dos_extended(blkid_probe pr, blkid_parttable tab, start = dos_partition_start(p) * ssf; size = dos_partition_size(p) * ssf; - if (size && is_extended(p)) - break; + if (size && is_extended(p)) { + if (start == 0) + DBG(LOWPROBE, blkid_debug("#%d: EBR link offset is zero -- ignore", i + 1)); + else + break; + } } if (i == 4) goto leave; diff --git a/libblkid/src/partitions/partitions.c b/libblkid/src/partitions/partitions.c index 752fc95..9d846ff 100644 --- a/libblkid/src/partitions/partitions.c +++ b/libblkid/src/partitions/partitions.c @@ -928,6 +928,20 @@ blkid_partition blkid_partlist_get_partition(blkid_partlist ls, int n) return &ls->parts[n]; } +blkid_partition blkid_partlist_get_partition_by_start(blkid_partlist ls, uint64_t start) +{ + int i, nparts; + blkid_partition par; + + nparts = blkid_partlist_numof_partitions(ls); + for (i = 0; i < nparts; i++) { + par = blkid_partlist_get_partition(ls, i); + if ((uint64_t) blkid_partition_get_start(par) == start) + return par; + } + return NULL; +} + /** * blkid_partlist_devno_to_partition: * @ls: partitions list diff --git a/libblkid/src/partitions/partitions.h b/libblkid/src/partitions/partitions.h index 61763bf..4e99e2a 100644 --- a/libblkid/src/partitions/partitions.h +++ b/libblkid/src/partitions/partitions.h @@ -20,6 +20,8 @@ extern int blkid_partlist_increment_partno(blkid_partlist ls); extern blkid_partition blkid_partlist_get_parent(blkid_partlist ls); +extern blkid_partition blkid_partlist_get_partition_by_start(blkid_partlist ls, uint64_t start); + extern int blkid_partitions_do_subprobe(blkid_probe pr, blkid_partition parent, const struct blkid_idinfo *id); -- 2.7.4