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| author |   Vaibhav Jain <vaibhav@linux.ibm.com> | 2019-09-27 11:50:02 +0530 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2019-10-10 20:15:53 +1100 |
| commit | 612ee81b9461475b5a5612c2e8d71559dd3c7920 (patch) | |
| tree | 36eeb3aeaaa1b767b2fe786d0b8b1dc74591d509 | |
| parent | Linux 5.4-rc2 (diff) | |
| download | linux-dev-612ee81b9461475b5a5612c2e8d71559dd3c7920.tar.xz linux-dev-612ee81b9461475b5a5612c2e8d71559dd3c7920.zip | |
powerpc/papr_scm: Fix an off-by-one check in papr_scm_meta_{get, set}
A validation check to prevent out of bounds read/write inside
functions papr_scm_meta_{get,set}() is off-by-one that prevent reads
and writes to the last byte of the label area.
This bug manifests as a failure to probe a dimm when libnvdimm is
unable to read the entire config-area as advertised by
ND_CMD_GET_CONFIG_SIZE. This usually happens when there are large
number of namespaces created in the region backed by the dimm and the
label-index spans max possible config-area. An error of the form below
usually reported in the kernel logs:
[ 255.293912] nvdimm: probe of nmem0 failed with error -22
The patch fixes these validation checks there by letting libnvdimm
access the entire config-area.
Fixes: 53e80bd042773('powerpc/nvdimm: Add support for multibyte read/write for metadata')
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190927062002.3169-1-vaibhav@linux.ibm.com
| -rw-r--r-- | arch/powerpc/platforms/pseries/papr_scm.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c index 61883291defc..ee07d0718bf1 100644 --- a/arch/powerpc/platforms/pseries/papr_scm.c +++ b/arch/powerpc/platforms/pseries/papr_scm.c @@ -152,7 +152,7 @@ static int papr_scm_meta_get(struct papr_scm_priv *p, int len, read; int64_t ret; - if ((hdr->in_offset + hdr->in_length) >= p->metadata_size) + if ((hdr->in_offset + hdr->in_length) > p->metadata_size) return -EINVAL; for (len = hdr->in_length; len; len -= read) { @@ -206,7 +206,7 @@ static int papr_scm_meta_set(struct papr_scm_priv *p, __be64 data_be; int64_t ret; - if ((hdr->in_offset + hdr->in_length) >= p->metadata_size) + if ((hdr->in_offset + hdr->in_length) > p->metadata_size) return -EINVAL; for (len = hdr->in_length; len; len -= wrote) { |