From: Yongseok Koh Date: Wed, 12 Dec 2018 11:10:54 +0000 (-0800) Subject: malloc: fix finding maximum contiguous IOVA size X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=6d09256148567807b772347ec4ac363c4bcb6b5a;p=dpdk.git malloc: fix finding maximum contiguous IOVA size malloc_elem_find_max_iova_contig() could return invalid size due to a missing sanity check. The following gdb output shows how 'cur_size' can be invalid in find_biggest_element(). (gdb) p/x cur_size $4 = 0xffffffffffe42900 (gdb) p elem $1 = (struct malloc_elem *) 0x12e842000 (gdb) p *elem $2 = {heap = 0x7ffff7ff387c, prev = 0x12e831fc0, next = 0x12e842900, free_list = {le_next = 0x109538000, le_prev = 0x7ffff7ff3894}, msl = 0x7ffff7ff107c, state = ELEM_FREE, pad = 0, size = 2304} (gdb) p *elem->msl $5 = {{base_va = 0x100200000, addr_64 = 4297064448}, page_sz = 2097152, socket_id = 0, version = 790, len = 17179869184, external = 0, memseg_arr = {name = "memseg-2048k-0-0", '\000' , count = 493, len = 8192, elt_sz = 48, data = 0x10002e000, rwlock = {cnt = 0}}} Fixes: 9fe6bceafd51 ("malloc: add finding biggest free IOVA-contiguous element") Cc: stable@dpdk.org Signed-off-by: Yongseok Koh Acked-by: Anatoly Burakov --- diff --git a/lib/librte_eal/common/malloc_elem.c b/lib/librte_eal/common/malloc_elem.c index fcdb18120a..d54a528ed6 100644 --- a/lib/librte_eal/common/malloc_elem.c +++ b/lib/librte_eal/common/malloc_elem.c @@ -38,6 +38,10 @@ malloc_elem_find_max_iova_contig(struct malloc_elem *elem, size_t align) /* segment must start after header and with specified alignment */ contig_seg_start = RTE_PTR_ALIGN_CEIL(data_start, align); + /* return if aligned address is already out of malloc element */ + if (contig_seg_start > data_end) + return 0; + /* if we're in IOVA as VA mode, or if we're in legacy mode with * hugepages, all elements are IOVA-contiguous. however, we can only * make these assumptions about internal memory - externally allocated