From: Tom Zanussi Date: Mon, 25 Apr 2016 19:01:28 +0000 (-0500) Subject: tracing: Handle tracing_map_alloc_elts() error path correctly X-Git-Tag: v4.7-rc1~125^2~11 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=6e4cf657defa8fb06dbf9ed91adb78414758f259;p=karo-tx-linux.git tracing: Handle tracing_map_alloc_elts() error path correctly If tracing_map_elt_alloc() fails, it will return ERR_PTR() instead of NULL, so change the check to IS_ERROR(). We also need to set the failed entry in the map->elts array to NULL instead of ERR_PTR() so tracing_map_free_elts() doesn't try freeing an ERR_PTR(). tracing_map_free_elts() should also zero out what it frees so a reentrant call won't find previously freed elements. Link: http://lkml.kernel.org/r/f29d03b00bce3aac8cf151a8a30e6c83e5fee66d.1461610073.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt --- diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c index e7dfc5eec669..0a689bbb78ef 100644 --- a/kernel/trace/tracing_map.c +++ b/kernel/trace/tracing_map.c @@ -366,10 +366,13 @@ static void tracing_map_free_elts(struct tracing_map *map) if (!map->elts) return; - for (i = 0; i < map->max_elts; i++) + for (i = 0; i < map->max_elts; i++) { tracing_map_elt_free(*(TRACING_MAP_ELT(map->elts, i))); + *(TRACING_MAP_ELT(map->elts, i)) = NULL; + } tracing_map_array_free(map->elts); + map->elts = NULL; } static int tracing_map_alloc_elts(struct tracing_map *map) @@ -383,7 +386,8 @@ static int tracing_map_alloc_elts(struct tracing_map *map) for (i = 0; i < map->max_elts; i++) { *(TRACING_MAP_ELT(map->elts, i)) = tracing_map_elt_alloc(map); - if (!(*(TRACING_MAP_ELT(map->elts, i)))) { + if (IS_ERR(*(TRACING_MAP_ELT(map->elts, i)))) { + *(TRACING_MAP_ELT(map->elts, i)) = NULL; tracing_map_free_elts(map); return -ENOMEM;