From: Andreas Fenkart afenkart@gmail.com
For double buffering to work, the target buffer must always be big enough to hold all data. This can only be ensured if buffers are of equal size, otherwise one must be smaller and we risk data loss when copying from the bigger to the smaller buffer.
Signed-off-by: Andreas Fenkart andreas.fenkart@digitalstrom.com --- tools/env/fw_env.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-)
diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c index 692abda..b1c8217 100644 --- a/tools/env/fw_env.c +++ b/tools/env/fw_env.c @@ -1382,18 +1382,19 @@ static int parse_config(struct env_opts *opts) return -1; }
- if (HaveRedundEnv && stat (DEVNAME (1), &st)) { - fprintf (stderr, - "Cannot access MTD device %s: %s\n", - DEVNAME (1), strerror (errno)); - return -1; - } + if (HaveRedundEnv) { + if (stat(DEVNAME(1), &st)) { + fprintf(stderr, + "Cannot access MTD device %s: %s\n", + DEVNAME(1), strerror(errno)); + return -1; + }
- if (HaveRedundEnv && ENVSIZE(0) != ENVSIZE(1)) { - ENVSIZE(0) = ENVSIZE(1) = min(ENVSIZE(0), ENVSIZE(1)); - fprintf(stderr, - "Redundant environments have inequal size, set to 0x%08lx\n", - ENVSIZE(1)); + if (ENVSIZE(0) != ENVSIZE(1)) { + fprintf(stderr, + "Redundant environments have unequal size"); + return -1; + } }
usable_envsize = CUR_ENVSIZE - sizeof(uint32_t);