commit: bf69d41d198138e3c601e9a6645f4f1369aff7e0 From: Eric Paris <[email protected]> Date: Thu, 28 Apr 2011 15:55:52 -0400 Subject: [PATCH] flex_arrays: allow zero length flex arrays
Just like kmalloc will allow one to allocate a 0 length segment of memory flex arrays should do the same thing. It should bomb if you try to use something, but it should at least allow the allocation. This is needed because when SELinux switched to using flex_arrays in 2.6.38 the inability to allocate a 0 length array resulted in SELinux policy load returning -ENOSPC when previously it worked. Based-on-patch-by: Steffen Klassert <[email protected]> Signed-off-by: Eric Paris <[email protected]> Tested-by: Chris Richards <[email protected]> Cc: [email protected] [2.6.38+] --- lib/flex_array.c | 11 ++++++++++- 1 files changed, 10 insertions(+), 1 deletions(-) diff --git a/lib/flex_array.c b/lib/flex_array.c index 0c33b24..854b57b 100644 --- a/lib/flex_array.c +++ b/lib/flex_array.c @@ -253,9 +253,16 @@ int flex_array_prealloc(struct flex_array *fa, unsigned int start, unsigned int end; struct flex_array_part *part; + if (!start && !nr_elements) + return 0; + if (start >= fa->total_nr_elements) + return -ENOSPC; + if (!nr_elements) + return 0; + end = start + nr_elements - 1; - if (start >= fa->total_nr_elements || end >= fa->total_nr_elements) + if (end >= fa->total_nr_elements) return -ENOSPC; if (elements_fit_in_base(fa)) return 0; @@ -346,6 +353,8 @@ int flex_array_shrink(struct flex_array *fa) int part_nr; int ret = 0; + if (!fa->total_nr_elements) + return 0; if (elements_fit_in_base(fa)) return ret; for (part_nr = 0; part_nr < FLEX_ARRAY_NR_BASE_PTRS; part_nr++) { _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
