From bc87af1314325b00c6ac002a60a2b0f0caa81e34 Mon Sep 17 00:00:00 2001 From: Xiao Ni Date: Sat, 18 Mar 2017 10:33:44 +0800 Subject: [PATCH 3/5] Replace snprintf with strncpy at some places to avoid truncation In gcc7 there are some building errors like: directive output may be truncated writing up to 31 bytes into a region of size 24 snprintf(str, MPB_SIG_LEN, %s, mpb->sig); It just need to copy one string to target. So use strncpy to replace it. For this line code: snprintf(str, MPB_SIG_LEN, %s, mpb->sig); Because mpb->sig has the content of version after magic, so it's better to use strncpy to replace snprintf too. Signed-off-by: Xiao Ni Signed-off-by: Jes Sorensen --- Upstream-Status: Backport super-intel.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/super-intel.c b/super-intel.c index 57c7e75..5499098 100644 --- a/super-intel.c +++ b/super-intel.c @@ -1811,7 +1811,8 @@ static void examine_super_imsm(struct supertype *st, char *homehost) __u32 reserved = imsm_reserved_sectors(super, super->disks); struct dl *dl; - snprintf(str, MPB_SIG_LEN, "%s", mpb->sig); + strncpy(str, (char *)mpb->sig, MPB_SIG_LEN); + str[MPB_SIG_LEN-1] = '\0'; printf(" Magic : %s\n", str); snprintf(str, strlen(MPB_VERSION_RAID0), "%s", get_imsm_version(mpb)); printf(" Version : %s\n", get_imsm_version(mpb)); @@ -7142,14 +7143,16 @@ static int update_subarray_imsm(struct supertype *st, char *subarray, u->type = update_rename_array; u->dev_idx = vol; - snprintf((char *) u->name, MAX_RAID_SERIAL_LEN, "%s", name); + strncpy((char *) u->name, name, MAX_RAID_SERIAL_LEN); + u->name[MAX_RAID_SERIAL_LEN-1] = '\0'; append_metadata_update(st, u, sizeof(*u)); } else { struct imsm_dev *dev; int i; dev = get_imsm_dev(super, vol); - snprintf((char *) dev->volume, MAX_RAID_SERIAL_LEN, "%s", name); + strncpy((char *) dev->volume, name, MAX_RAID_SERIAL_LEN); + dev->volume[MAX_RAID_SERIAL_LEN-1] = '\0'; for (i = 0; i < mpb->num_raid_devs; i++) { dev = get_imsm_dev(super, i); handle_missing(super, dev); -- 2.12.2