ce36394269
Anonymous mappings should ignore offset but shared anonymous mapping
forgot to clear it and makes the following legit test program trigger
SIGBUS.
#include <sys/mman.h>
#include <stdio.h>
#include <errno.h>
#define PAGE_SIZE 4096
int main(void)
{
char *p;
int i;
p = mmap(NULL, 2 * PAGE_SIZE, PROT_READ|PROT_WRITE,
MAP_SHARED|MAP_ANONYMOUS, -1, PAGE_SIZE);
if (p == MAP_FAILED) {
perror("mmap");
return 1;
}
for (i = 0; i < 2; i++) {
printf("page %d\n", i);
p[i * 4096] = i;
}
return 0;
}
Fix it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Hugh Dickins <hugh@veritas.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>