On Mon, Nov 28, 2016 at 3:13 PM, Neil Horman <nhorman@xxxxxxxxxxxxx> wrote: > On Mon, Nov 28, 2016 at 02:00:19PM +0100, Andrey Konovalov wrote: >> Hi! >> >> I've got the following error report while running the syzkaller fuzzer. >> >> On commit d8e435f3ab6fea2ea324dce72b51dd7761747523 (Nov 26). >> >> A reproducer is attached. >> >> a.out: vmalloc: allocation failure, allocated 823562240 of 1427091456 >> bytes, mode:0x24000c2(GFP_KERNEL|__GFP_HIGHMEM) >> > How much total ram do you have in this system? The call appears to be > attempting to allocate 1.3 Gb of data. Even using vmalloc to allow > discontiguous allocation, thats alot of memory, and if enough is in use already, > I could make the argument that this might be expected behavior. Hi Neail, I have 2 Gb. Just tested with 4 Gb, everything seems to be working fine. So I guess this is not actually a bug and allocating 1.3 Gb is OK. Thanks! > > Neil > >> oom_reaper: reaped process 3810 (a.out), now anon-rss:0kB, >> file-rss:0kB, shmem-rss:0kB >> a.out invoked oom-killer: >> gfp_mask=0x24002c2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN), nodemask=0, >> order=0, oom_score_adj=0 >> a.out cpuset=/ mems_allowed=0 >> CPU: 0 PID: 3814 Comm: a.out Not tainted 4.9.0-rc6+ #457 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> ffff880068667380 ffffffff81c73b14 ffff880068667710 ffff88006b469018 >> ffff880068667718 0000000000000000 ffff880068667400 ffffffff81641a87 >> 0000000000000000 0000000000000000 0000000000000297 ffffffff84d37280 >> Call Trace: >> [< inline >] __dump_stack lib/dump_stack.c:15 >> [<ffffffff81c73b14>] dump_stack+0xb3/0x10f lib/dump_stack.c:51 >> [<ffffffff81641a87>] dump_header.isra.21+0x16f/0x5f5 mm/oom_kill.c:416 >> [<ffffffff8154bad8>] oom_kill_process+0x4d8/0xab0 mm/oom_kill.c:835 >> [<ffffffff8154c77c>] out_of_memory+0x2dc/0x1790 mm/oom_kill.c:1044 >> [< inline >] __alloc_pages_may_oom mm/page_alloc.c:3086 >> [<ffffffff8155afb6>] __alloc_pages_slowpath+0x1886/0x1bf0 mm/page_alloc.c:3683 >> [<ffffffff8155b8e2>] __alloc_pages_nodemask+0x5c2/0x710 mm/page_alloc.c:3781 >> [<ffffffff816236a4>] alloc_pages_current+0xf4/0x400 mm/mempolicy.c:2072 >> [< inline >] alloc_pages ./include/linux/gfp.h:469 >> [< inline >] __vmalloc_area_node mm/vmalloc.c:1631 >> [<ffffffff815f8eab>] __vmalloc_node_range+0x33b/0x690 mm/vmalloc.c:1691 >> [< inline >] __vmalloc_node mm/vmalloc.c:1734 >> [< inline >] __vmalloc_node_flags mm/vmalloc.c:1748 >> [<ffffffff815f92cb>] vmalloc+0x5b/0x70 mm/vmalloc.c:1763 >> [<ffffffff82fd0893>] xt_alloc_table_info+0x83/0x120 >> net/netfilter/x_tables.c:961 >> [< inline >] do_replace net/ipv4/netfilter/ip_tables.c:1140 >> [<ffffffff8335b420>] do_ipt_set_ctl+0x210/0x420 >> net/ipv4/netfilter/ip_tables.c:1687 >> [< inline >] nf_sockopt net/netfilter/nf_sockopt.c:105 >> [<ffffffff82efdab7>] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:114 >> [<ffffffff831be741>] ip_setsockopt+0xa1/0xb0 net/ipv4/ip_sockglue.c:1231 >> [<ffffffff832700d5>] udp_setsockopt+0x45/0x80 net/ipv4/udp.c:2085 >> [<ffffffff8346b31f>] ipv6_setsockopt+0x11f/0x140 net/ipv6/ipv6_sockglue.c:892 >> [<ffffffff83a6cd5d>] sctp_setsockopt+0x15d/0x3d70 net/sctp/socket.c:3788 >> [<ffffffff82ca40e6>] sock_common_setsockopt+0x96/0xd0 net/core/sock.c:2690 >> [< inline >] SYSC_setsockopt net/socket.c:1757 >> [<ffffffff82ca10c4>] SyS_setsockopt+0x154/0x240 net/socket.c:1736 >> [<ffffffff840f2c41>] entry_SYSCALL_64_fastpath+0x1f/0xc2 >> arch/x86/entry/entry_64.S:209 >> CPU: 1 PID: 3810 Comm: a.out Not tainted 4.9.0-rc6+ #457 >> Mem-Info: >> active_anon:1938 inactive_anon:75 isolated_anon:0 >> active_file:14 inactive_file:30 isolated_file:4 >> unevictable:0 dirty:0 writeback:0 unstable:0 >> slab_reclaimable:3316 slab_unreclaimable:9767 >> mapped:21 shmem:81 pagetables:309 bounce:0 >> free:1 free_pcp:75 free_cma:0 >> Node 0 active_anon:7752kB inactive_anon:300kB active_file:56kB >> inactive_file:120kB unevictable:0kB isolated(anon):0kB >> isolated(file):16kB mapped:84kB dirty:0kB writeback:0kB shmem:324kB >> writeback_tmp:0kB unstable:0kB pages_scanned:134 all_unreclaimable? no >> Node 0 DMA free:4kB min:48kB low:60kB high:72kB active_anon:0kB >> inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB >> writepending:0kB present:15992kB managed:15908kB mlocked:0kB >> slab_reclaimable:0kB slab_unreclaimable:8kB kernel_stack:0kB >> pagetables:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB >> lowmem_reserve[]: 0 1641 1641 1641 >> Node 0 DMA32 free:0kB min:5156kB low:6836kB high:8516kB >> active_anon:7752kB inactive_anon:300kB active_file:56kB >> inactive_file:120kB unevictable:0kB writepending:0kB present:2080760kB >> managed:1684640kB mlocked:0kB slab_reclaimable:13264kB >> slab_unreclaimable:39060kB kernel_stack:2944kB pagetables:1236kB >> bounce:0kB free_pcp:300kB local_pcp:120kB free_cma:0kB >> lowmem_reserve[]: 0 0 0 0 >> Node 0 DMA: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB >> 0*1024kB 0*2048kB 0*4096kB = 0kB >> Node 0 DMA32: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB >> 0*1024kB 0*2048kB 0*4096kB = 0kB >> Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB >> 148 total pagecache pages >> 0 pages in swap cache >> Swap cache stats: add 0, delete 0, find 0/0 >> Free swap = 0kB >> Total swap = 0kB >> 524188 pages RAM >> 0 pages HighMem/MovableOnly >> 99051 pages reserved >> [ pid ] uid tgid total_vm rss nr_ptes nr_pmds swapents >> oom_score_adj name >> 0 1767 5346 133 16 3 0 -1000 udevd >> 0 1876 5315 122 15 3 0 -1000 udevd >> 0 1877 5315 122 15 3 0 -1000 udevd >> 0 3541 2493 573 8 3 0 0 dhclient >> 0 3676 13231 171 22 3 0 0 rsyslogd >> 0 3725 4725 52 15 3 0 0 cron >> 0 3751 12490 155 28 3 0 -1000 sshd >> 0 3775 3694 43 13 3 0 0 getty >> 0 3776 3694 43 13 3 0 0 getty >> 0 3777 3694 42 13 3 0 0 getty >> 0 3778 3694 41 13 3 0 0 getty >> 0 3779 3694 44 13 3 0 0 getty >> 0 3780 3694 43 13 3 0 0 getty >> 0 3785 3649 44 12 3 0 0 getty >> 0 3797 17818 205 39 3 0 0 sshd >> 0 3800 4474 126 15 3 0 0 bash >> 0 3804 2053 22 9 3 0 0 a.out >> 0 3805 2053 26 9 3 0 0 a.out >> 0 3806 18488 0 18 3 0 0 a.out > >> // autogenerated by syzkaller (http://github.com/google/syzkaller) >> >> #ifndef __NR_mmap >> #define __NR_mmap 9 >> #endif >> #ifndef __NR_setsockopt >> #define __NR_setsockopt 54 >> #endif >> #ifndef __NR_syz_fuse_mount >> #define __NR_syz_fuse_mount 1000004 >> #endif >> #ifndef __NR_socket >> #define __NR_socket 41 >> #endif >> #ifndef __NR_syz_emit_ethernet >> #define __NR_syz_emit_ethernet 1000006 >> #endif >> #ifndef __NR_syz_fuseblk_mount >> #define __NR_syz_fuseblk_mount 1000005 >> #endif >> #ifndef __NR_syz_open_dev >> #define __NR_syz_open_dev 1000002 >> #endif >> #ifndef __NR_syz_open_pts >> #define __NR_syz_open_pts 1000003 >> #endif >> #ifndef __NR_syz_test >> #define __NR_syz_test 1000001 >> #endif >> >> #define SYZ_SANDBOX_NONE 1 >> #define SYZ_REPEAT 1 >> >> #define _GNU_SOURCE >> >> #include <sys/ioctl.h> >> #include <sys/mount.h> >> #include <sys/prctl.h> >> #include <sys/resource.h> >> #include <sys/socket.h> >> #include <sys/stat.h> >> #include <sys/syscall.h> >> #include <sys/time.h> >> #include <sys/types.h> >> #include <sys/wait.h> >> >> #include <linux/capability.h> >> #include <linux/if.h> >> #include <linux/if_tun.h> >> #include <linux/sched.h> >> #include <net/if_arp.h> >> >> #include <assert.h> >> #include <dirent.h> >> #include <errno.h> >> #include <fcntl.h> >> #include <grp.h> >> #include <pthread.h> >> #include <setjmp.h> >> #include <signal.h> >> #include <stdarg.h> >> #include <stddef.h> >> #include <stdint.h> >> #include <stdio.h> >> #include <stdlib.h> >> #include <string.h> >> #include <unistd.h> >> >> const int kFailStatus = 67; >> const int kErrorStatus = 68; >> const int kRetryStatus = 69; >> >> __attribute__((noreturn)) void fail(const char* msg, ...) >> { >> int e = errno; >> fflush(stdout); >> va_list args; >> va_start(args, msg); >> vfprintf(stderr, msg, args); >> va_end(args); >> fprintf(stderr, " (errno %d)\n", e); >> exit(kFailStatus); >> } >> >> __attribute__((noreturn)) void exitf(const char* msg, ...) >> { >> int e = errno; >> fflush(stdout); >> va_list args; >> va_start(args, msg); >> vfprintf(stderr, msg, args); >> va_end(args); >> fprintf(stderr, " (errno %d)\n", e); >> exit(kRetryStatus); >> } >> >> static int flag_debug; >> >> void debug(const char* msg, ...) >> { >> if (!flag_debug) >> return; >> va_list args; >> va_start(args, msg); >> vfprintf(stdout, msg, args); >> va_end(args); >> fflush(stdout); >> } >> >> __thread int skip_segv; >> __thread jmp_buf segv_env; >> >> static void segv_handler(int sig, siginfo_t* info, void* uctx) >> { >> if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED)) >> _longjmp(segv_env, 1); >> exit(sig); >> } >> >> static void install_segv_handler() >> { >> struct sigaction sa; >> memset(&sa, 0, sizeof(sa)); >> sa.sa_sigaction = segv_handler; >> sa.sa_flags = SA_NODEFER | SA_SIGINFO; >> sigaction(SIGSEGV, &sa, NULL); >> sigaction(SIGBUS, &sa, NULL); >> } >> >> #define NONFAILING(...) \ >> { \ >> __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ >> if (_setjmp(segv_env) == 0) { \ >> __VA_ARGS__; \ >> } \ >> __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ >> } >> >> static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t a2) >> { >> if (a0 == 0xc || a0 == 0xb) { >> char buf[128]; >> sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", >> (uint8_t)a1, (uint8_t)a2); >> return open(buf, O_RDWR, 0); >> } else { >> char buf[1024]; >> char* hash; >> strncpy(buf, (char*)a0, sizeof(buf)); >> buf[sizeof(buf) - 1] = 0; >> while ((hash = strchr(buf, '#'))) { >> *hash = '0' + (char)(a1 % 10); >> a1 /= 10; >> } >> return open(buf, a2, 0); >> } >> } >> >> static uintptr_t syz_open_pts(uintptr_t a0, uintptr_t a1) >> { >> int ptyno = 0; >> if (ioctl(a0, TIOCGPTN, &ptyno)) >> return -1; >> char buf[128]; >> sprintf(buf, "/dev/pts/%d", ptyno); >> return open(buf, a1, 0); >> } >> >> static uintptr_t syz_fuse_mount(uintptr_t a0, uintptr_t a1, >> uintptr_t a2, uintptr_t a3, >> uintptr_t a4, uintptr_t a5) >> { >> uint64_t target = a0; >> uint64_t mode = a1; >> uint64_t uid = a2; >> uint64_t gid = a3; >> uint64_t maxread = a4; >> uint64_t flags = a5; >> >> int fd = open("/dev/fuse", O_RDWR); >> if (fd == -1) >> return fd; >> char buf[1024]; >> sprintf(buf, "fd=%d,user_id=%ld,group_id=%ld,rootmode=0%o", fd, >> (long)uid, (long)gid, (unsigned)mode & ~3u); >> if (maxread != 0) >> sprintf(buf + strlen(buf), ",max_read=%ld", (long)maxread); >> if (mode & 1) >> strcat(buf, ",default_permissions"); >> if (mode & 2) >> strcat(buf, ",allow_other"); >> syscall(SYS_mount, "", target, "fuse", flags, buf); >> return fd; >> } >> >> static uintptr_t syz_fuseblk_mount(uintptr_t a0, uintptr_t a1, >> uintptr_t a2, uintptr_t a3, >> uintptr_t a4, uintptr_t a5, >> uintptr_t a6, uintptr_t a7) >> { >> uint64_t target = a0; >> uint64_t blkdev = a1; >> uint64_t mode = a2; >> uint64_t uid = a3; >> uint64_t gid = a4; >> uint64_t maxread = a5; >> uint64_t blksize = a6; >> uint64_t flags = a7; >> >> int fd = open("/dev/fuse", O_RDWR); >> if (fd == -1) >> return fd; >> if (syscall(SYS_mknodat, AT_FDCWD, blkdev, S_IFBLK, makedev(7, 199))) >> return fd; >> char buf[256]; >> sprintf(buf, "fd=%d,user_id=%ld,group_id=%ld,rootmode=0%o", fd, >> (long)uid, (long)gid, (unsigned)mode & ~3u); >> if (maxread != 0) >> sprintf(buf + strlen(buf), ",max_read=%ld", (long)maxread); >> if (blksize != 0) >> sprintf(buf + strlen(buf), ",blksize=%ld", (long)blksize); >> if (mode & 1) >> strcat(buf, ",default_permissions"); >> if (mode & 2) >> strcat(buf, ",allow_other"); >> syscall(SYS_mount, blkdev, target, "fuseblk", flags, buf); >> return fd; >> } >> >> static uintptr_t execute_syscall(int nr, uintptr_t a0, uintptr_t a1, >> uintptr_t a2, uintptr_t a3, >> uintptr_t a4, uintptr_t a5, >> uintptr_t a6, uintptr_t a7, >> uintptr_t a8) >> { >> switch (nr) { >> default: >> return syscall(nr, a0, a1, a2, a3, a4, a5); >> case __NR_syz_test: >> return 0; >> case __NR_syz_open_dev: >> return syz_open_dev(a0, a1, a2); >> case __NR_syz_open_pts: >> return syz_open_pts(a0, a1); >> case __NR_syz_fuse_mount: >> return syz_fuse_mount(a0, a1, a2, a3, a4, a5); >> case __NR_syz_fuseblk_mount: >> return syz_fuseblk_mount(a0, a1, a2, a3, a4, a5, a6, a7); >> } >> } >> >> static void setup_main_process() >> { >> struct sigaction sa; >> memset(&sa, 0, sizeof(sa)); >> sa.sa_handler = SIG_IGN; >> syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); >> syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); >> install_segv_handler(); >> >> char tmpdir_template[] = "./syzkaller.XXXXXX"; >> char* tmpdir = mkdtemp(tmpdir_template); >> if (!tmpdir) >> fail("failed to mkdtemp"); >> if (chmod(tmpdir, 0777)) >> fail("failed to chmod"); >> if (chdir(tmpdir)) >> fail("failed to chdir"); >> } >> >> static void loop(); >> >> static void sandbox_common() >> { >> prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); >> setpgrp(); >> setsid(); >> >> struct rlimit rlim; >> rlim.rlim_cur = rlim.rlim_max = 128 << 20; >> setrlimit(RLIMIT_AS, &rlim); >> rlim.rlim_cur = rlim.rlim_max = 1 << 20; >> setrlimit(RLIMIT_FSIZE, &rlim); >> rlim.rlim_cur = rlim.rlim_max = 1 << 20; >> setrlimit(RLIMIT_STACK, &rlim); >> rlim.rlim_cur = rlim.rlim_max = 0; >> setrlimit(RLIMIT_CORE, &rlim); >> >> unshare(CLONE_NEWNS); >> unshare(CLONE_NEWIPC); >> unshare(CLONE_IO); >> } >> >> static int do_sandbox_none() >> { >> int pid = fork(); >> if (pid) >> return pid; >> sandbox_common(); >> loop(); >> exit(1); >> } >> >> static void remove_dir(const char* dir) >> { >> DIR* dp; >> struct dirent* ep; >> int iter = 0; >> int i; >> retry: >> dp = opendir(dir); >> if (dp == NULL) { >> if (errno == EMFILE) { >> exitf("opendir(%s) failed due to NOFILE, exiting"); >> } >> exitf("opendir(%s) failed", dir); >> } >> while ((ep = readdir(dp))) { >> if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) >> continue; >> char filename[FILENAME_MAX]; >> snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); >> struct stat st; >> if (lstat(filename, &st)) >> exitf("lstat(%s) failed", filename); >> if (S_ISDIR(st.st_mode)) { >> remove_dir(filename); >> continue; >> } >> for (i = 0;; i++) { >> debug("unlink(%s)\n", filename); >> if (unlink(filename) == 0) >> break; >> if (errno == EROFS) { >> debug("ignoring EROFS\n"); >> break; >> } >> if (errno != EBUSY || i > 100) >> exitf("unlink(%s) failed", filename); >> debug("umount(%s)\n", filename); >> if (umount2(filename, MNT_DETACH)) >> exitf("umount(%s) failed", filename); >> } >> } >> closedir(dp); >> for (i = 0;; i++) { >> debug("rmdir(%s)\n", dir); >> if (rmdir(dir) == 0) >> break; >> if (i < 100) { >> if (errno == EROFS) { >> debug("ignoring EROFS\n"); >> break; >> } >> if (errno == EBUSY) { >> debug("umount(%s)\n", dir); >> if (umount2(dir, MNT_DETACH)) >> exitf("umount(%s) failed", dir); >> continue; >> } >> if (errno == ENOTEMPTY) { >> if (iter < 100) { >> iter++; >> goto retry; >> } >> } >> } >> exitf("rmdir(%s) failed", dir); >> } >> } >> >> static uint64_t current_time_ms() >> { >> struct timespec ts; >> >> if (clock_gettime(CLOCK_MONOTONIC, &ts)) >> fail("clock_gettime failed"); >> return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; >> } >> >> static void test(); >> >> void loop() >> { >> int iter; >> for (iter = 0;; iter++) { >> char cwdbuf[256]; >> sprintf(cwdbuf, "./%d", iter); >> if (mkdir(cwdbuf, 0777)) >> fail("failed to mkdir"); >> int pid = fork(); >> if (pid < 0) >> fail("clone failed"); >> if (pid == 0) { >> prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); >> setpgrp(); >> if (chdir(cwdbuf)) >> fail("failed to chdir"); >> test(); >> exit(0); >> } >> int status = 0; >> uint64_t start = current_time_ms(); >> for (;;) { >> int res = waitpid(pid, &status, __WALL | WNOHANG); >> int errno0 = errno; >> if (res == pid) >> break; >> usleep(1000); >> if (current_time_ms() - start > 5 * 1000) { >> kill(-pid, SIGKILL); >> kill(pid, SIGKILL); >> waitpid(pid, &status, __WALL); >> break; >> } >> } >> remove_dir(cwdbuf); >> } >> } >> >> long r[5]; >> void* thr(void* arg) >> { >> switch ((long)arg) { >> case 0: >> r[0] = >> execute_syscall(__NR_mmap, 0x20000000ul, 0xa000ul, 0x3ul, >> 0x32ul, 0xfffffffffffffffful, 0x0ul, 0, 0, 0); >> break; >> case 1: >> r[1] = execute_syscall(__NR_socket, 0xaul, 0x5ul, 0x84ul, 0, 0, 0, >> 0, 0, 0); >> break; >> case 2: >> r[2] = execute_syscall(__NR_socket, 0x1ful, 0x3ul, 0x6ul, 0, 0, 0, >> 0, 0, 0); >> break; >> case 3: >> NONFAILING(memcpy( >> (void*)0x20009000, >> "\x83\x15\xf6\xdb\x47\x14\xae\xe2\x8d\xb8\x4d\xb9\x0f\x32\xe7" >> "\xf5\xbc\xa6\xae\x9a\x2f\x19\xed\xf0\x75\x6a\x0b\xf0\x00\xe9" >> "\xe1\x0e\xb4\xa5\x19\x08\x88\xfc\x8b\x2d\xe2\x9a\x0f\x55\x00" >> "\x00\x00\x00\x00\x08\x27\xab\x8e\x7d\xcb\xcc\x15\x4e\x79\xe2" >> "\xd9\xca\x15\xc3\x66\xbd\x44\xa8\x53\x1f\xda\xab\xce\x98\x39" >> "\x40\x4e\x75\x57\xfd\x57\xc0\x01\x0b\xb0", >> 85)); >> r[4] = execute_syscall(__NR_setsockopt, r[1], 0x0ul, 0x40ul, >> 0x20009000ul, 0x55ul, 0, 0, 0, 0); >> break; >> } >> return 0; >> } >> >> void test() >> { >> long i; >> pthread_t th[8]; >> >> memset(r, -1, sizeof(r)); >> srand(getpid()); >> for (i = 0; i < 4; i++) { >> pthread_create(&th[i], 0, thr, (void*)i); >> usleep(10000); >> } >> for (i = 0; i < 4; i++) { >> pthread_create(&th[4 + i], 0, thr, (void*)i); >> if (rand() % 2) >> usleep(rand() % 10000); >> } >> usleep(100000); >> } >> >> int main() >> { >> setup_main_process(); >> int pid = do_sandbox_none(); >> int status = 0; >> while (waitpid(pid, &status, __WALL) != pid) { >> } >> return 0; >> } > -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
