* stack overflow in printk_all_partitions.
@ 2012-05-09 19:58 Dave Jones
2012-05-14 21:03 ` [PATCH] block: fix buffer overflow when printing partition UUIDs Tejun Heo
0 siblings, 1 reply; 3+ messages in thread
From: Dave Jones @ 2012-05-09 19:58 UTC (permalink / raw)
To: Linux Kernel; +Cc: Szymon Gruszczynski, Fedora Kernel Team, Al Viro, Tejun Heo
Szymon (cc'd) reported this oops that prevents his machine booting
a 3.3.4 kernel.
[ 2.892504] Kernel panic - not syncing: stack-protector: Kernel stack corrupted in: ffffffff81b14c7e
[ 2.892506]
[ 2.892872] [<ffffffff815e226b>] panic+0xba/0x1c6
[ 2.892961] [<ffffffff81b14c7e>] ? printk_all_partitions+0x259/0x26xb
[ 2.893057] [<ffffffff810566bb>] __stack_chk_fail+0x1b/0x20
[ 2.893147] [<ffffffff81b15c7e>] printk_all_paritions+0x259/0x26xb
[ 2.893244] [<ffffffff81aedfe0>] mount_block_root+0x1bc/0x27f
[ 2.893336] [<ffffffff81aee0fa>] mount_root+0x57/0x5b
[ 2.893425] [<ffffffff81aee23b>] prepare_namespace+0x13d/0x176
[ 2.893522] [<ffffffff8107eec0>] ? release_tgcred.isra.4+0x330/0x30
[ 2.893616] [<ffffffff81aedd60>] kernel_init+0x155/0x15a
[ 2.893708] [<ffffffff81087b97>] ? schedule_tail+0x27/0xb0
[ 2.893800] [<ffffffff815f4d24>] kernel_thread_helper+0x5/0x10
[ 2.893893] [<ffffffff81aedc0b>] ? start_kernel+0x3c5/0x3c5
[ 2.893984] [<ffffffff815f4d20>] ? gs_change+0x13/0x13
His partition tables don't look anything out of the ordinary to me.
http://wklej.org/id/748085/
Any ideas what's going wrong here ?
original report at https://bugzilla.redhat.com/show_bug.cgi?id=819624,
though all pertinent info so far is captured above.
Dave
^ permalink raw reply [flat|nested] 3+ messages in thread
* [PATCH] block: fix buffer overflow when printing partition UUIDs
2012-05-09 19:58 stack overflow in printk_all_partitions Dave Jones
@ 2012-05-14 21:03 ` Tejun Heo
2012-05-15 6:22 ` Jens Axboe
0 siblings, 1 reply; 3+ messages in thread
From: Tejun Heo @ 2012-05-14 21:03 UTC (permalink / raw)
To: Dave Jones, Jens Axboe
Cc: Linux Kernel, Szymon Gruszczynski, Fedora Kernel Team, Al Viro
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
---
block/genhd.c | 10 ++++++----
include/linux/genhd.h | 6 ------
2 files changed, 6 insertions(+), 10 deletions(-)
diff --git a/block/genhd.c b/block/genhd.c
index df9816e..9cf5583 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)
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index e61d319..017a7fb 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -222,12 +222,6 @@ static inline void part_pack_uuid(const u8 *uuid_str, u8 *to)
}
}
-static inline char *part_unpack_uuid(const u8 *uuid, char *out)
-{
- sprintf(out, "%pU", uuid);
- return out;
-}
-
static inline int disk_max_parts(struct gendisk *disk)
{
if (disk->flags & GENHD_FL_EXT_DEVT)
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] block: fix buffer overflow when printing partition UUIDs
2012-05-14 21:03 ` [PATCH] block: fix buffer overflow when printing partition UUIDs Tejun Heo
@ 2012-05-15 6:22 ` Jens Axboe
0 siblings, 0 replies; 3+ messages in thread
From: Jens Axboe @ 2012-05-15 6:22 UTC (permalink / raw)
To: Tejun Heo
Cc: Dave Jones, Linux Kernel, Szymon Gruszczynski, Fedora Kernel Team,
Al Viro
On 05/14/2012 11:03 PM, Tejun Heo wrote:
> 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().
Ooops, thanks Tejun, applied for current branch.
--
Jens Axboe
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2012-05-15 6:22 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-05-09 19:58 stack overflow in printk_all_partitions Dave Jones
2012-05-14 21:03 ` [PATCH] block: fix buffer overflow when printing partition UUIDs Tejun Heo
2012-05-15 6:22 ` Jens Axboe
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).