* [PATCH v2] md : Replace snprintf with scnprintf
@ 2022-08-23 18:51 Saurabh Sengar
2022-09-19 16:47 ` Saurabh Singh Sengar
0 siblings, 1 reply; 3+ messages in thread
From: Saurabh Sengar @ 2022-08-23 18:51 UTC (permalink / raw)
To: song, shli, neilb, linux-raid, linux-kernel, ssengar, mikelley,
guoqing.jiang
Current code produces a warning as shown below when total characters
in the constituent block device names plus the slashes exceeds 200.
snprintf() returns the number of characters generated from the given
input, which could cause the expression “200 – len” to wrap around
to a large positive number. Fix this by using scnprintf() instead,
which returns the actual number of characters written into the buffer.
[ 1513.267938] ------------[ cut here ]------------
[ 1513.267943] WARNING: CPU: 15 PID: 37247 at <snip>/lib/vsprintf.c:2509 vsnprintf+0x2c8/0x510
[ 1513.267944] Modules linked in: <snip>
[ 1513.267969] CPU: 15 PID: 37247 Comm: mdadm Not tainted 5.4.0-1085-azure #90~18.04.1-Ubuntu
[ 1513.267969] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022
[ 1513.267971] RIP: 0010:vsnprintf+0x2c8/0x510
<-snip->
[ 1513.267982] Call Trace:
[ 1513.267986] snprintf+0x45/0x70
[ 1513.267990] ? disk_name+0x71/0xa0
[ 1513.267993] dump_zones+0x114/0x240 [raid0]
[ 1513.267996] ? _cond_resched+0x19/0x40
[ 1513.267998] raid0_run+0x19e/0x270 [raid0]
[ 1513.268000] md_run+0x5e0/0xc50
[ 1513.268003] ? security_capable+0x3f/0x60
[ 1513.268005] do_md_run+0x19/0x110
[ 1513.268006] md_ioctl+0x195e/0x1f90
[ 1513.268007] blkdev_ioctl+0x91f/0x9f0
[ 1513.268010] block_ioctl+0x3d/0x50
[ 1513.268012] do_vfs_ioctl+0xa9/0x640
[ 1513.268014] ? __fput+0x162/0x260
[ 1513.268016] ksys_ioctl+0x75/0x80
[ 1513.268017] __x64_sys_ioctl+0x1a/0x20
[ 1513.268019] do_syscall_64+0x5e/0x200
[ 1513.268021] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 766038846e875 ("md/raid0: replace printk() with pr_*()")
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
---
V2 :
- Rebase
drivers/md/raid0.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index 78addfe..857c493 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -47,7 +47,7 @@ static void dump_zones(struct mddev *mddev)
int len = 0;
for (k = 0; k < conf->strip_zone[j].nb_dev; k++)
- len += snprintf(line+len, 200-len, "%s%pg", k?"/":"",
+ len += scnprintf(line+len, 200-len, "%s%pg", k?"/":"",
conf->devlist[j * raid_disks + k]->bdev);
pr_debug("md: zone%d=[%s]\n", j, line);
--
1.8.3.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* RE: [PATCH v2] md : Replace snprintf with scnprintf
2022-08-23 18:51 [PATCH v2] md : Replace snprintf with scnprintf Saurabh Sengar
@ 2022-09-19 16:47 ` Saurabh Singh Sengar
2022-09-19 18:09 ` Song Liu
0 siblings, 1 reply; 3+ messages in thread
From: Saurabh Singh Sengar @ 2022-09-19 16:47 UTC (permalink / raw)
To: Saurabh Sengar, song, shli, neilb, linux-raid, linux-kernel,
Michael Kelley (LINUX),
guoqing.jiang
Is this queued for 6.0 ?
> -----Original Message-----
> From: Saurabh Sengar <ssengar@linux.microsoft.com>
> Sent: Wednesday, August 24, 2022 12:21 AM
> To: song@kernel.org; shli@fb.com; neilb@suse.com; linux-
> raid@vger.kernel.org; linux-kernel@vger.kernel.org; Saurabh Singh Sengar
> <ssengar@microsoft.com>; Michael Kelley (LINUX)
> <mikelley@microsoft.com>; guoqing.jiang@linux.dev
> Subject: [PATCH v2] md : Replace snprintf with scnprintf
>
> Current code produces a warning as shown below when total characters in
> the constituent block device names plus the slashes exceeds 200.
> snprintf() returns the number of characters generated from the given input,
> which could cause the expression “200 – len” to wrap around to a large
> positive number. Fix this by using scnprintf() instead, which returns the
> actual number of characters written into the buffer.
>
> [ 1513.267938] ------------[ cut here ]------------ [ 1513.267943] WARNING:
> CPU: 15 PID: 37247 at <snip>/lib/vsprintf.c:2509 vsnprintf+0x2c8/0x510 [
> 1513.267944] Modules linked in: <snip> [ 1513.267969] CPU: 15 PID: 37247
> Comm: mdadm Not tainted 5.4.0-1085-azure #90~18.04.1-Ubuntu [
> 1513.267969] Hardware name: Microsoft Corporation Virtual Machine/Virtual
> Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022 [ 1513.267971] RIP:
> 0010:vsnprintf+0x2c8/0x510 <-snip-> [ 1513.267982] Call Trace:
> [ 1513.267986] snprintf+0x45/0x70
> [ 1513.267990] ? disk_name+0x71/0xa0
> [ 1513.267993] dump_zones+0x114/0x240 [raid0] [ 1513.267996] ?
> _cond_resched+0x19/0x40 [ 1513.267998] raid0_run+0x19e/0x270 [raid0] [
> 1513.268000] md_run+0x5e0/0xc50 [ 1513.268003] ?
> security_capable+0x3f/0x60 [ 1513.268005] do_md_run+0x19/0x110 [
> 1513.268006] md_ioctl+0x195e/0x1f90 [ 1513.268007]
> blkdev_ioctl+0x91f/0x9f0 [ 1513.268010] block_ioctl+0x3d/0x50 [
> 1513.268012] do_vfs_ioctl+0xa9/0x640 [ 1513.268014] ? __fput+0x162/0x260
> [ 1513.268016] ksys_ioctl+0x75/0x80 [ 1513.268017]
> __x64_sys_ioctl+0x1a/0x20 [ 1513.268019] do_syscall_64+0x5e/0x200 [
> 1513.268021] entry_SYSCALL_64_after_hwframe+0x44/0xa9
>
> Fixes: 766038846e875 ("md/raid0: replace printk() with pr_*()")
> Reviewed-by: Michael Kelley <mikelley@microsoft.com>
> Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
> Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
> ---
> V2 :
> - Rebase
>
> drivers/md/raid0.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index 78addfe..857c493
> 100644
> --- a/drivers/md/raid0.c
> +++ b/drivers/md/raid0.c
> @@ -47,7 +47,7 @@ static void dump_zones(struct mddev *mddev)
> int len = 0;
>
> for (k = 0; k < conf->strip_zone[j].nb_dev; k++)
> - len += snprintf(line+len, 200-len, "%s%pg", k?"/":"",
> + len += scnprintf(line+len, 200-len, "%s%pg", k?"/":"",
> conf->devlist[j * raid_disks + k]->bdev);
> pr_debug("md: zone%d=[%s]\n", j, line);
>
> --
> 1.8.3.1
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v2] md : Replace snprintf with scnprintf
2022-09-19 16:47 ` Saurabh Singh Sengar
@ 2022-09-19 18:09 ` Song Liu
0 siblings, 0 replies; 3+ messages in thread
From: Song Liu @ 2022-09-19 18:09 UTC (permalink / raw)
To: Saurabh Singh Sengar
Cc: Saurabh Sengar, shli, neilb, linux-raid, linux-kernel,
Michael Kelley (LINUX),
guoqing.jiang
On Mon, Sep 19, 2022 at 9:47 AM Saurabh Singh Sengar
<ssengar@microsoft.com> wrote:
>
> Is this queued for 6.0 ?
This is queued for 6.1.
Thanks,
Song
>
> > -----Original Message-----
> > From: Saurabh Sengar <ssengar@linux.microsoft.com>
> > Sent: Wednesday, August 24, 2022 12:21 AM
> > To: song@kernel.org; shli@fb.com; neilb@suse.com; linux-
> > raid@vger.kernel.org; linux-kernel@vger.kernel.org; Saurabh Singh Sengar
> > <ssengar@microsoft.com>; Michael Kelley (LINUX)
> > <mikelley@microsoft.com>; guoqing.jiang@linux.dev
> > Subject: [PATCH v2] md : Replace snprintf with scnprintf
> >
> > Current code produces a warning as shown below when total characters in
> > the constituent block device names plus the slashes exceeds 200.
> > snprintf() returns the number of characters generated from the given input,
> > which could cause the expression “200 – len” to wrap around to a large
> > positive number. Fix this by using scnprintf() instead, which returns the
> > actual number of characters written into the buffer.
> >
> > [ 1513.267938] ------------[ cut here ]------------ [ 1513.267943] WARNING:
> > CPU: 15 PID: 37247 at <snip>/lib/vsprintf.c:2509 vsnprintf+0x2c8/0x510 [
> > 1513.267944] Modules linked in: <snip> [ 1513.267969] CPU: 15 PID: 37247
> > Comm: mdadm Not tainted 5.4.0-1085-azure #90~18.04.1-Ubuntu [
> > 1513.267969] Hardware name: Microsoft Corporation Virtual Machine/Virtual
> > Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022 [ 1513.267971] RIP:
> > 0010:vsnprintf+0x2c8/0x510 <-snip-> [ 1513.267982] Call Trace:
> > [ 1513.267986] snprintf+0x45/0x70
> > [ 1513.267990] ? disk_name+0x71/0xa0
> > [ 1513.267993] dump_zones+0x114/0x240 [raid0] [ 1513.267996] ?
> > _cond_resched+0x19/0x40 [ 1513.267998] raid0_run+0x19e/0x270 [raid0] [
> > 1513.268000] md_run+0x5e0/0xc50 [ 1513.268003] ?
> > security_capable+0x3f/0x60 [ 1513.268005] do_md_run+0x19/0x110 [
> > 1513.268006] md_ioctl+0x195e/0x1f90 [ 1513.268007]
> > blkdev_ioctl+0x91f/0x9f0 [ 1513.268010] block_ioctl+0x3d/0x50 [
> > 1513.268012] do_vfs_ioctl+0xa9/0x640 [ 1513.268014] ? __fput+0x162/0x260
> > [ 1513.268016] ksys_ioctl+0x75/0x80 [ 1513.268017]
> > __x64_sys_ioctl+0x1a/0x20 [ 1513.268019] do_syscall_64+0x5e/0x200 [
> > 1513.268021] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> >
> > Fixes: 766038846e875 ("md/raid0: replace printk() with pr_*()")
> > Reviewed-by: Michael Kelley <mikelley@microsoft.com>
> > Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
> > Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
> > ---
> > V2 :
> > - Rebase
> >
> > drivers/md/raid0.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index 78addfe..857c493
> > 100644
> > --- a/drivers/md/raid0.c
> > +++ b/drivers/md/raid0.c
> > @@ -47,7 +47,7 @@ static void dump_zones(struct mddev *mddev)
> > int len = 0;
> >
> > for (k = 0; k < conf->strip_zone[j].nb_dev; k++)
> > - len += snprintf(line+len, 200-len, "%s%pg", k?"/":"",
> > + len += scnprintf(line+len, 200-len, "%s%pg", k?"/":"",
> > conf->devlist[j * raid_disks + k]->bdev);
> > pr_debug("md: zone%d=[%s]\n", j, line);
> >
> > --
> > 1.8.3.1
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2022-09-19 18:10 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2022-08-23 18:51 [PATCH v2] md : Replace snprintf with scnprintf Saurabh Sengar
2022-09-19 16:47 ` Saurabh Singh Sengar
2022-09-19 18:09 ` Song Liu
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