[Minios-devel] [PATCH] lib/ukallocbbuddy: fix addmem call with negative len

[Hugo Lefeuvre <hugo.lefeuvre@xxxxxxxxx>]

Whenever len == metalen, the init region has exactly the size of the
allocator metadata. In this case there is no space left for anything else
and max - min - metalen is negative: calling bbuddy_addmem doesn't make
sense.

Only call bbuddy_addmem if there's memory left in the region.
---
 lib/ukallocbbuddy/bbuddy.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/ukallocbbuddy/bbuddy.c b/lib/ukallocbbuddy/bbuddy.c
index 2a35de0..85f3e8d 100644
--- a/lib/ukallocbbuddy/bbuddy.c
+++ b/lib/ukallocbbuddy/bbuddy.c
@@ -508,8 +508,11 @@ struct uk_alloc *uk_allocbbuddy_init(void *base, size_t 
len)
        a->availmem = bbuddy_availmem;
 #endif
 
-       /* add left memory - ignore return value */
-       bbuddy_addmem(a, (void *)(min + metalen),
-                     (size_t)(max - min - metalen));
+       if (max > min + metalen) {
+               /* add left memory - ignore return value */
+               bbuddy_addmem(a, (void *)(min + metalen),
+                                (size_t)(max - min - metalen));
+       }
+
        return a;
 }
-- 
2.7.4


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