From: Rafał Miłecki rafal@milecki.pl
Call to fread() was changed to check for return value. The problem is it can't be checked for returning 1 (as it is) to determine success.
We call fread() with buffer size as "size" argument. Reading any "compatible" value shorter than buffer size will result in returning 0 even on success.
Modify code to use fstat() to determine expected read length.
This fixes regression that broke using fw_env with NVMEM devices.
Fixes: c059a22b7776 ("tools: env: fw_env: Fix unused-result warning") Cc: Jaehoon Chung jh80.chung@samsung.com Signed-off-by: Rafał Miłecki rafal@milecki.pl --- tools/env/fw_env.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c index c9a8774ace..bf8b7ba304 100644 --- a/tools/env/fw_env.c +++ b/tools/env/fw_env.c @@ -1732,6 +1732,7 @@ static int find_nvmem_device(void) }
while (!nvmem && (dent = readdir(dir))) { + struct stat s; FILE *fp; size_t size;
@@ -1749,14 +1750,22 @@ static int find_nvmem_device(void) continue; }
- size = fread(buf, sizeof(buf), 1, fp); + if (fstat(fileno(fp), &s)) { + fprintf(stderr, "Failed to fstat %s\n", comp); + goto next; + } + + if (s.st_size >= sizeof(buf)) { + goto next; + } + + size = fread(buf, s.st_size, 1, fp); if (size != 1) { fprintf(stderr, "read failed about %s\n", comp); - fclose(fp); - return -EIO; + goto next; } - + buf[s.st_size] = '\0';
if (!strcmp(buf, "u-boot,env")) { bytes = asprintf(&nvmem, "%s/%s/nvmem", path, dent->d_name); @@ -1765,6 +1774,7 @@ static int find_nvmem_device(void) } }
+next: fclose(fp); }