From: "Uladzislau Rezki (Sony)" urezki@gmail.com
mainline inclusion from mainline-5.2-rc1 commit a6cf4e0fe3e740ed7af39fdda721e1ac12247dd3 category: bugfix bugzilla: 15766, https://bugzilla.openeuler.org/show_bug.cgi?id=25 CVE: NA
------------------------------------------------- This macro adds some debug code to check that vmap allocations are happened in ascending order.
By default this option is set to 0 and not active. It requires recompilation of the kernel to activate it. Set to 1, compile the kernel.
[urezki@gmail.com: v4] Link: http://lkml.kernel.org/r/20190406183508.25273-4-urezki@gmail.com Link: http://lkml.kernel.org/r/20190402162531.10888-4-urezki@gmail.com Signed-off-by: Uladzislau Rezki (Sony) urezki@gmail.com Reviewed-by: Roman Gushchin guro@fb.com Cc: Ingo Molnar mingo@elte.hu Cc: Joel Fernandes joelaf@google.com Cc: Matthew Wilcox willy@infradead.org Cc: Michal Hocko mhocko@suse.com Cc: Oleksiy Avramchenko oleksiy.avramchenko@sonymobile.com Cc: Steven Rostedt rostedt@goodmis.org Cc: Tejun Heo tj@kernel.org Cc: Thomas Garnier thgarnie@google.com Cc: Thomas Gleixner tglx@linutronix.de Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org (cherry picked from commit a6cf4e0fe3e740ed7af39fdda721e1ac12247dd3) Signed-off-by: Kefeng Wang wangkefeng.wang@huawei.com Reviewed-by: Hanjun Guo guohanjun@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- mm/vmalloc.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 557e46f73ab7..b246ebe224c4 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -326,6 +326,7 @@ EXPORT_SYMBOL(vmalloc_to_pfn); /*** Global kva allocator ***/
#define DEBUG_AUGMENT_PROPAGATE_CHECK 0 +#define DEBUG_AUGMENT_LOWEST_MATCH_CHECK 0
#define VM_LAZY_FREE 0x02 #define VM_VM_AREA 0x04 @@ -834,6 +835,44 @@ find_vmap_lowest_match(unsigned long size, return NULL; }
+#if DEBUG_AUGMENT_LOWEST_MATCH_CHECK +#include <linux/random.h> + +static struct vmap_area * +find_vmap_lowest_linear_match(unsigned long size, + unsigned long align, unsigned long vstart) +{ + struct vmap_area *va; + + list_for_each_entry(va, &free_vmap_area_list, list) { + if (!is_within_this_va(va, size, align, vstart)) + continue; + + return va; + } + + return NULL; +} + +static void +find_vmap_lowest_match_check(unsigned long size) +{ + struct vmap_area *va_1, *va_2; + unsigned long vstart; + unsigned int rnd; + + get_random_bytes(&rnd, sizeof(rnd)); + vstart = VMALLOC_START + rnd; + + va_1 = find_vmap_lowest_match(size, 1, vstart); + va_2 = find_vmap_lowest_linear_match(size, 1, vstart); + + if (va_1 != va_2) + pr_emerg("not lowest: t: 0x%p, l: 0x%p, v: 0x%lx\n", + va_1, va_2, vstart); +} +#endif + enum fit_type { NOTHING_FIT = 0, FL_FIT_TYPE = 1, /* full fit */ @@ -976,6 +1015,10 @@ __alloc_vmap_area(unsigned long size, unsigned long align, if (ret) return vend;
+#if DEBUG_AUGMENT_LOWEST_MATCH_CHECK + find_vmap_lowest_match_check(size); +#endif + return nva_start_addr; }