From 597b52f6ca247086371abd67e5083292a500e736 Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Thu, 13 Mar 2014 16:36:14 +0200 Subject: [PATCH] libceph: fixup error handling in osdmap_decode() The existing error handling scheme requires resetting err to -EINVAL prior to calling any ceph_decode_* macro. This is ugly and fragile, and there already are a few places where we would return 0 on error, due to a missing reset. Fix this by adding a special e_inval label to be used by all ceph_decode_* macros. Signed-off-by: Ilya Dryomov Reviewed-by: Alex Elder --- net/ceph/osdmap.c | 53 ++++++++++++++++++++++++----------------------- 1 file changed, 27 insertions(+), 26 deletions(-) diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c index a82df6ea0749..298d076eee89 100644 --- a/net/ceph/osdmap.c +++ b/net/ceph/osdmap.c @@ -688,36 +688,37 @@ static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map) { u16 version; u32 len, max, i; - int err = -EINVAL; u32 epoch = 0; void *start = *p; + int err; struct ceph_pg_pool_info *pi; dout("%s %p to %p len %d\n", __func__, *p, end, (int)(end - *p)); - ceph_decode_16_safe(p, end, version, bad); + ceph_decode_16_safe(p, end, version, e_inval); if (version > 6) { pr_warning("got unknown v %d > 6 of osdmap\n", version); - goto bad; + goto e_inval; } if (version < 6) { pr_warning("got old v %d < 6 of osdmap\n", version); - goto bad; + goto e_inval; } - ceph_decode_need(p, end, 2*sizeof(u64)+6*sizeof(u32), bad); + ceph_decode_need(p, end, 2*sizeof(u64)+6*sizeof(u32), e_inval); ceph_decode_copy(p, &map->fsid, sizeof(map->fsid)); epoch = map->epoch = ceph_decode_32(p); ceph_decode_copy(p, &map->created, sizeof(map->created)); ceph_decode_copy(p, &map->modified, sizeof(map->modified)); - ceph_decode_32_safe(p, end, max, bad); + ceph_decode_32_safe(p, end, max, e_inval); while (max--) { - ceph_decode_need(p, end, 8 + 2, bad); - err = -ENOMEM; + ceph_decode_need(p, end, 8 + 2, e_inval); pi = kzalloc(sizeof(*pi), GFP_NOFS); - if (!pi) + if (!pi) { + err = -ENOMEM; goto bad; + } pi->id = ceph_decode_64(p); err = __decode_pool(p, end, pi); if (err < 0) { @@ -728,27 +729,25 @@ static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map) } err = __decode_pool_names(p, end, map); - if (err < 0) { - dout("fail to decode pool names"); + if (err) goto bad; - } - ceph_decode_32_safe(p, end, map->pool_max, bad); + ceph_decode_32_safe(p, end, map->pool_max, e_inval); - ceph_decode_32_safe(p, end, map->flags, bad); + ceph_decode_32_safe(p, end, map->flags, e_inval); max = ceph_decode_32(p); /* (re)alloc osd arrays */ err = osdmap_set_max_osd(map, max); - if (err < 0) + if (err) goto bad; /* osds */ - err = -EINVAL; ceph_decode_need(p, end, 3*sizeof(u32) + map->max_osd*(1 + sizeof(*map->osd_weight) + - sizeof(*map->osd_addr)), bad); + sizeof(*map->osd_addr)), e_inval); + *p += 4; /* skip length field (should match max) */ ceph_decode_copy(p, map->osd_state, map->max_osd); @@ -762,7 +761,7 @@ static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map) ceph_decode_addr(&map->osd_addr[i]); /* pg_temp */ - ceph_decode_32_safe(p, end, len, bad); + ceph_decode_32_safe(p, end, len, e_inval); for (i = 0; i < len; i++) { int n, j; struct ceph_pg pgid; @@ -771,16 +770,16 @@ static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map) err = ceph_decode_pgid(p, end, &pgid); if (err) goto bad; - ceph_decode_need(p, end, sizeof(u32), bad); + ceph_decode_need(p, end, sizeof(u32), e_inval); n = ceph_decode_32(p); - err = -EINVAL; if (n > (UINT_MAX - sizeof(*pg)) / sizeof(u32)) - goto bad; - ceph_decode_need(p, end, n * sizeof(u32), bad); - err = -ENOMEM; + goto e_inval; + ceph_decode_need(p, end, n * sizeof(u32), e_inval); pg = kmalloc(sizeof(*pg) + n*sizeof(u32), GFP_NOFS); - if (!pg) + if (!pg) { + err = -ENOMEM; goto bad; + } pg->pgid = pgid; pg->len = n; for (j = 0; j < n; j++) @@ -794,10 +793,10 @@ static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map) } /* crush */ - ceph_decode_32_safe(p, end, len, bad); + ceph_decode_32_safe(p, end, len, e_inval); dout("osdmap_decode crush len %d from off 0x%x\n", len, (int)(*p - start)); - ceph_decode_need(p, end, len, bad); + ceph_decode_need(p, end, len, e_inval); map->crush = crush_decode(*p, end); *p += len; if (IS_ERR(map->crush)) { @@ -812,6 +811,8 @@ static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map) dout("full osdmap epoch %d max_osd %d\n", map->epoch, map->max_osd); return 0; +e_inval: + err = -EINVAL; bad: pr_err("corrupt full osdmap (%d) epoch %d off %d (%p of %p-%p)\n", err, epoch, (int)(*p - start), *p, start, end); -- 2.30.2