5.4-stable review patch. If anyone has any objections, please let me know.
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From: Daniel Mentz danielmentz@google.com
[ Upstream commit a75a16c62a2540f11eeae4f2b50e95deefb652ea ]
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 Link: https://lore.kernel.org/r/20231017182026.2141163-1-danielmentz@google.com Reviewed-by: Avri Altman avri.altman@wdc.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/ufs/ufshcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 9d13226d2324a..363adf489079a 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3265,7 +3265,7 @@ 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++)