There is a general misunderstanding amongst engineers that {v}snprintf()
returns the length of the data *actually* encoded into the destination
array.  However, as per the C99 standard {v}snprintf() really returns
the length of the data that *would have been* written if there were
enough space for it.  This misunderstanding has led to buffer-overruns
in the past.  It's generally considered safer to use the {v}scnprintf()
variants in their place (or even sprintf() in simple cases).  So let's
do that.

Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Signed-off-by: Lee Jones <l...@kernel.org>
---
Cc: Hannes Reinecke <h...@suse.com>
Cc: "James E.J. Bottomley" <j...@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.peter...@oracle.com>
Cc: Lee Jones <l...@kernel.org>
Cc: linux-s...@vger.kernel.org
---
 drivers/scsi/aic7xxx/aicasm/aicasm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/aic7xxx/aicasm/aicasm.c 
b/drivers/scsi/aic7xxx/aicasm/aicasm.c
index 8d995186e557a..bc758e78d3c06 100644
--- a/drivers/scsi/aic7xxx/aicasm/aicasm.c
+++ b/drivers/scsi/aic7xxx/aicasm/aicasm.c
@@ -331,7 +331,7 @@ back_patch()
                        if (cur_instr->patch_label->type != LABEL) {
                                char buf[255];
 
-                               snprintf(buf, sizeof(buf),
+                               scnprintf(buf, sizeof(buf),
                                         "Undefined label %s",
                                         cur_instr->patch_label->name);
                                stop(buf, EX_DATAERR);
-- 
2.43.0.594.gd9cf4e227d-goog


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