From ce5155c4f8226f4816f9f7cb88149ec275c7b0a8 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Tue, 18 Feb 2020 22:43:15 -0500
Subject: [PATCH 1/3] compat sysinfo(2): don't bother with field-by-field
copyout
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
kernel/sys.c | 33 +++++++++++++++++----------------
1 file changed, 17 insertions(+), 16 deletions(-)
diff --git a/kernel/sys.c b/kernel/sys.c
index d325f3ab624a9..b4a0324a0699d 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2634,6 +2634,7 @@ struct compat_sysinfo {
COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
{
struct sysinfo s;
+ struct compat_sysinfo s_32;
do_sysinfo(&s);
@@ -2658,23 +2659,23 @@ COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
s.freehigh >>= bitcount;
}
- if (!access_ok(info, sizeof(struct compat_sysinfo)) ||
- __put_user(s.uptime, &info->uptime) ||
- __put_user(s.loads[0], &info->loads[0]) ||
- __put_user(s.loads[1], &info->loads[1]) ||
- __put_user(s.loads[2], &info->loads[2]) ||
- __put_user(s.totalram, &info->totalram) ||
- __put_user(s.freeram, &info->freeram) ||
- __put_user(s.sharedram, &info->sharedram) ||
- __put_user(s.bufferram, &info->bufferram) ||
- __put_user(s.totalswap, &info->totalswap) ||
- __put_user(s.freeswap, &info->freeswap) ||
- __put_user(s.procs, &info->procs) ||
- __put_user(s.totalhigh, &info->totalhigh) ||
- __put_user(s.freehigh, &info->freehigh) ||
- __put_user(s.mem_unit, &info->mem_unit))
+ memset(&s_32, 0, sizeof(s_32));
+ s_32.uptime = s.uptime;
+ s_32.loads[0] = s.loads[0];
+ s_32.loads[1] = s.loads[1];
+ s_32.loads[2] = s.loads[2];
+ s_32.totalram = s.totalram;
+ s_32.freeram = s.freeram;
+ s_32.sharedram = s.sharedram;
+ s_32.bufferram = s.bufferram;
+ s_32.totalswap = s.totalswap;
+ s_32.freeswap = s.freeswap;
+ s_32.procs = s.procs;
+ s_32.totalhigh = s.totalhigh;
+ s_32.freehigh = s.freehigh;
+ s_32.mem_unit = s.mem_unit;
+ if (copy_to_user(info, &s_32, sizeof(s_32)))
return -EFAULT;
-
return 0;
}
#endif /* CONFIG_COMPAT */
From a656d47a010b74e390c4336efc0f617886ab407c Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 12 Feb 2020 11:36:05 -0500
Subject: [PATCH 2/3] scsi_ioctl.c: switch SCSI_IOCTL_GET_IDLUN to
copy_to_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
drivers/scsi/scsi_ioctl.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/scsi/scsi_ioctl.c b/drivers/scsi/scsi_ioctl.c
index 8f3af87b6bb0c..45d04b7b26439 100644
--- a/drivers/scsi/scsi_ioctl.c
+++ b/drivers/scsi/scsi_ioctl.c
@@ -211,18 +211,18 @@ static int scsi_ioctl_common(struct scsi_device *sdev, int cmd, void __user *arg
}
switch (cmd) {
- case SCSI_IOCTL_GET_IDLUN:
- if (!access_ok(arg, sizeof(struct scsi_idlun)))
+ case SCSI_IOCTL_GET_IDLUN: {
+ struct scsi_idlun v = {
+ .dev_id = (sdev->id & 0xff)
+ + ((sdev->lun & 0xff) << 8)
+ + ((sdev->channel & 0xff) << 16)
+ + ((sdev->host->host_no & 0xff) << 24),
+ .host_unique_id = sdev->host->unique_id
+ };
+ if (copy_to_user(arg, &v, sizeof(struct scsi_idlun)))
return -EFAULT;
-
- __put_user((sdev->id & 0xff)
- + ((sdev->lun & 0xff) << 8)
- + ((sdev->channel & 0xff) << 16)
- + ((sdev->host->host_no & 0xff) << 24),
- &((struct scsi_idlun __user *)arg)->dev_id);
- __put_user(sdev->host->unique_id,
- &((struct scsi_idlun __user *)arg)->host_unique_id);
return 0;
+ }
case SCSI_IOCTL_GET_BUS_NUMBER:
return put_user(sdev->host->host_no, (int __user *)arg);
case SCSI_IOCTL_PROBE_HOST:
From ebe6976d3634a311367f72c2402f148ab9f23920 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 19 Mar 2020 18:08:59 -0400
Subject: [PATCH 3/3] pcm_native: result of put_user() needs to be checked
... and no, __put_user() doesn't help here - skipping
access_ok() on the second call does not remove the
possibility of page having become unmapped or r/o
in the meanwhile
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
sound/core/pcm_native.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index aef8602562783..47838f57a6477 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -3093,7 +3093,8 @@ static int snd_pcm_xferi_frames_ioctl(struct snd_pcm_substream *substream,
result = snd_pcm_lib_write(substream, xferi.buf, xferi.frames);
else
result = snd_pcm_lib_read(substream, xferi.buf, xferi.frames);
- __put_user(result, &_xferi->result);
+ if (put_user(result, &_xferi->result))
+ return -EFAULT;
return result < 0 ? result : 0;
}
@@ -3122,7 +3123,8 @@ static int snd_pcm_xfern_frames_ioctl(struct snd_pcm_substream *substream,
else
result = snd_pcm_lib_readv(substream, bufs, xfern.frames);
kfree(bufs);
- __put_user(result, &_xfern->result);
+ if (put_user(result, &_xfern->result))
+ return -EFAULT;
return result < 0 ? result : 0;
}
@@ -3137,7 +3139,8 @@ static int snd_pcm_rewind_ioctl(struct snd_pcm_substream *substream,
if (put_user(0, _frames))
return -EFAULT;
result = snd_pcm_rewind(substream, frames);
- __put_user(result, _frames);
+ if (put_user(result, _frames))
+ return -EFAULT;
return result < 0 ? result : 0;
}
@@ -3152,7 +3155,8 @@ static int snd_pcm_forward_ioctl(struct snd_pcm_substream *substream,
if (put_user(0, _frames))
return -EFAULT;
result = snd_pcm_forward(substream, frames);
- __put_user(result, _frames);
+ if (put_user(result, _frames))
+ return -EFAULT;
return result < 0 ? result : 0;
}