summaryrefslogtreecommitdiff
path: root/block/genhd.c
diff options
context:
space:
mode:
authorTejun Heo <tj@kernel.org>2012-05-15 08:22:04 +0200
committerJens Axboe <axboe@kernel.dk>2012-05-15 08:22:04 +0200
commit05c69d298c96703741cac9a5cbbf6c53bd55a6e2 (patch)
treea9918d8c056adcd527b6cdf23ec9dc26e585efe9 /block/genhd.c
parent85fd0bc95bc76d129db0d0114c40665745bbba07 (diff)
downloadkernel-05c69d298c96703741cac9a5cbbf6c53bd55a6e2.tar.gz
block: fix buffer overflow when printing partition UUIDs
6d1d8050b4bc8 "block, partition: add partition_meta_info to hd_struct" added part_unpack_uuid() which assumes that the passed in buffer has enough space for sprintfing "%pU" - 37 characters including '\0'. Unfortunately, b5af921ec0233 "init: add support for root devices specified by partition UUID" supplied 33 bytes buffer to the function leading to the following panic with stackprotector enabled. Kernel panic - not syncing: stack-protector: Kernel stack corrupted in: ffffffff81b14c7e [<ffffffff815e226b>] panic+0xba/0x1c6 [<ffffffff81b14c7e>] ? printk_all_partitions+0x259/0x26xb [<ffffffff810566bb>] __stack_chk_fail+0x1b/0x20 [<ffffffff81b15c7e>] printk_all_paritions+0x259/0x26xb [<ffffffff81aedfe0>] mount_block_root+0x1bc/0x27f [<ffffffff81aee0fa>] mount_root+0x57/0x5b [<ffffffff81aee23b>] prepare_namespace+0x13d/0x176 [<ffffffff8107eec0>] ? release_tgcred.isra.4+0x330/0x30 [<ffffffff81aedd60>] kernel_init+0x155/0x15a [<ffffffff81087b97>] ? schedule_tail+0x27/0xb0 [<ffffffff815f4d24>] kernel_thread_helper+0x5/0x10 [<ffffffff81aedc0b>] ? start_kernel+0x3c5/0x3c5 [<ffffffff815f4d20>] ? gs_change+0x13/0x13 Increase the buffer size, remove the dangerous part_unpack_uuid() and use snprintf() directly from printk_all_partitions(). Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Szymon Gruszczynski <sz.gruszczynski@googlemail.com> Cc: Will Drewry <wad@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/genhd.c')
-rw-r--r--block/genhd.c10
1 files changed, 6 insertions, 4 deletions
diff --git a/block/genhd.c b/block/genhd.c
index df9816ede75b..9cf5583c90ff 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -743,7 +743,7 @@ void __init printk_all_partitions(void)
struct hd_struct *part;
char name_buf[BDEVNAME_SIZE];
char devt_buf[BDEVT_SIZE];
- u8 uuid[PARTITION_META_INFO_UUIDLTH * 2 + 1];
+ char uuid_buf[PARTITION_META_INFO_UUIDLTH * 2 + 5];
/*
* Don't show empty devices or things that have been
@@ -762,14 +762,16 @@ void __init printk_all_partitions(void)
while ((part = disk_part_iter_next(&piter))) {
bool is_part0 = part == &disk->part0;
- uuid[0] = 0;
+ uuid_buf[0] = '\0';
if (part->info)
- part_unpack_uuid(part->info->uuid, uuid);
+ snprintf(uuid_buf, sizeof(uuid_buf), "%pU",
+ part->info->uuid);
printk("%s%s %10llu %s %s", is_part0 ? "" : " ",
bdevt_str(part_devt(part), devt_buf),
(unsigned long long)part->nr_sects >> 1,
- disk_name(disk, part->partno, name_buf), uuid);
+ disk_name(disk, part->partno, name_buf),
+ uuid_buf);
if (is_part0) {
if (disk->driverfs_dev != NULL &&
disk->driverfs_dev->driver != NULL)