erofs: silence uninitialized variable warning in z_erofs_scan_folio()

Smatch complains that:

    fs/erofs/zdata.c:1047 z_erofs_scan_folio()
    error: uninitialized symbol 'err'.

The issue is if we hit this (!(map->m_flags & EROFS_MAP_MAPPED)) {
condition then "err" isn't set.  It's inside a loop so we would have to
hit that condition on every iteration.  Initialize "err" to zero to
solve this.

Fixes: 5b9654efb604 ("erofs: teach z_erofs_scan_folios() to handle multi-page folios")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/f78ab50e-ed6d-4275-8dd4-a4159fa565a2@stanley.mountain
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 544fa0f922b43b40c757202e281dbdd30b19e403..424f656cd765e24f3bd9c8bdf98bc8b09f33c706 100644 (file)
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -962,7 +962,7 @@ static int z_erofs_scan_folio(struct z_erofs_decompress_frontend *f,
        const unsigned int bs = i_blocksize(inode);
        unsigned int end = folio_size(folio), split = 0, cur, pgs;
        bool tight, excl;
-       int err;
+       int err = 0;
 
        tight = (bs == PAGE_SIZE);
        z_erofs_onlinefolio_init(folio);