| Message ID | 20231017182026.2141163-1-danielmentz@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | scsi: ufs: Leave space for '\0' in utf8 desc string | expand |
> utf16s_to_utf8s does not NULL terminate the output string. For us to be able > to add a NULL character when utf16s_to_utf8s returns, we need to make > sure that there is space for such NULL character at the end of the output > buffer. We can achieve this by passing an output buffer size to > utf16s_to_utf8s that is one character less than what we allocated. > > Other call sites of utf16s_to_utf8s appear to be using the same technique > where they artificially reduce the buffer size by one to leave space for a > NULL character or line feed character. > > Fixes: 4b828fe156a6 ("scsi: ufs: revamp string descriptor reading") I think this code goes back to commit b573d484e4ff (scsi: ufs: add support to read device and string descriptors) Reviewed-by: Avri Altman <avri.altman@wdc.com> > Reviewed-by: Mars Cheng <marscheng@google.com> > Reviewed-by: Bart Van Assche <bvanassche@acm.org> > Reviewed-by: Yen-lin Lai <yenlinlai@google.com> > Signed-off-by: Daniel Mentz <danielmentz@google.com> > --- > drivers/ufs/core/ufshcd.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index > 8382e8cfa414..5767642982c1 100644 > --- a/drivers/ufs/core/ufshcd.c > +++ b/drivers/ufs/core/ufshcd.c > @@ -3632,7 +3632,7 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, > u8 desc_index, > */ > ret = utf16s_to_utf8s(uc_str->uc, > uc_str->len - QUERY_DESC_HDR_SIZE, > - UTF16_BIG_ENDIAN, str, ascii_len); > + UTF16_BIG_ENDIAN, str, ascii_len - > + 1); > > /* replace non-printable or non-ASCII characters with spaces */ > for (i = 0; i < ret; i++) > -- > 2.42.0.655.g421f12c284-goog
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 8382e8cfa414..5767642982c1 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -3632,7 +3632,7 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, u8 desc_index, */ ret = utf16s_to_utf8s(uc_str->uc, uc_str->len - QUERY_DESC_HDR_SIZE, - UTF16_BIG_ENDIAN, str, ascii_len); + UTF16_BIG_ENDIAN, str, ascii_len - 1); /* replace non-printable or non-ASCII characters with spaces */ for (i = 0; i < ret; i++)
utf16s_to_utf8s does not NULL terminate the output string. For us to be able to add a NULL character when utf16s_to_utf8s returns, we need to make sure that there is space for such NULL character at the end of the output buffer. We can achieve this by passing an output buffer size to utf16s_to_utf8s that is one character less than what we allocated. Other call sites of utf16s_to_utf8s appear to be using the same technique where they artificially reduce the buffer size by one to leave space for a NULL character or line feed character. Fixes: 4b828fe156a6 ("scsi: ufs: revamp string descriptor reading") Reviewed-by: Mars Cheng <marscheng@google.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Yen-lin Lai <yenlinlai@google.com> Signed-off-by: Daniel Mentz <danielmentz@google.com> --- drivers/ufs/core/ufshcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)