On Mon, Feb 15, 2016 at 11:21 AM, Takashi Iwai tiwai@suse.de wrote:
On Mon, 15 Feb 2016 10:35:22 +0100, Dmitry Vyukov wrote:
Hello,
The following program causes memory leak of a 24K object allocated in snd_seq_pool_init:
// autogenerated by syzkaller (http://github.com/google/syzkaller) #include <pthread.h> #include <stdint.h> #include <string.h> #include <sys/syscall.h> #include <unistd.h>
long r[148];
void* thr(void* arg) { switch ((long)arg) { case 0: r[0] = syscall(SYS_mmap, 0x20000000ul, 0xe000ul, 0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul); break; case 1: r[2] = syscall(SYS_open, "/dev/snd/seq", 0x1ul, 0, 0, 0); break; case 2: *(uint32_t*)0x20008a90 = (uint32_t)0x6; *(uint32_t*)0x20008a94 = (uint32_t)0x4; *(uint32_t*)0x20008a98 = (uint32_t)0x200; *(uint8_t*)0x20008a9c = (uint8_t)0xfa5; *(uint8_t*)0x20008a9d = (uint8_t)0x100000000; *(uint8_t*)0x20008a9e = (uint8_t)0x0; *(uint8_t*)0x20008a9f = (uint8_t)0x3; *(uint8_t*)0x20008aa0 = (uint8_t)0x1; *(uint8_t*)0x20008aa1 = (uint8_t)0x1; *(uint8_t*)0x20008aa2 = (uint8_t)0x0; *(uint8_t*)0x20008aa3 = (uint8_t)0x40; *(uint8_t*)0x20008aa4 = (uint8_t)0x9; *(uint8_t*)0x20008aa5 = (uint8_t)0x9; *(uint8_t*)0x20008aa6 = (uint8_t)0x6; *(uint8_t*)0x20008aa7 = (uint8_t)0x80; *(uint8_t*)0x20008aa8 = (uint8_t)0x0; *(uint8_t*)0x20008aa9 = (uint8_t)0x5d34b2c3; *(uint8_t*)0x20008aaa = (uint8_t)0x3a7; *(uint8_t*)0x20008aab = (uint8_t)0x9; *(uint8_t*)0x20008aac = (uint8_t)0x8d62; *(uint8_t*)0x20008aad = (uint8_t)0x5; *(uint8_t*)0x20008aae = (uint8_t)0x7; *(uint8_t*)0x20008aaf = (uint8_t)0x20; *(uint8_t*)0x20008ab0 = (uint8_t)0x8; *(uint8_t*)0x20008ab1 = (uint8_t)0x7; *(uint8_t*)0x20008ab2 = (uint8_t)0xfffffffffffffffc; *(uint8_t*)0x20008ab3 = (uint8_t)0x7; *(uint8_t*)0x20008ab4 = (uint8_t)0x7ff; *(uint8_t*)0x20008ab5 = (uint8_t)0x1; *(uint8_t*)0x20008ab6 = (uint8_t)0x0; *(uint8_t*)0x20008ab7 = (uint8_t)0x9; *(uint8_t*)0x20008ab8 = (uint8_t)0x6; *(uint8_t*)0x20008ab9 = (uint8_t)0xfffffffffffffe00; *(uint8_t*)0x20008aba = (uint8_t)0x1000; *(uint8_t*)0x20008abb = (uint8_t)0xfffffffffffffffb; *(uint8_t*)0x20008abc = (uint8_t)0xcfd3; *(uint8_t*)0x20008abd = (uint8_t)0x101; *(uint8_t*)0x20008abe = (uint8_t)0x9; *(uint8_t*)0x20008abf = (uint8_t)0xfffffffffffffffc; *(uint8_t*)0x20008ac0 = (uint8_t)0xf2; *(uint8_t*)0x20008ac1 = (uint8_t)0x6; *(uint8_t*)0x20008ac2 = (uint8_t)0x0; *(uint8_t*)0x20008ac3 = (uint8_t)0x7fffffff; *(uint8_t*)0x20008ac4 = (uint8_t)0x4; *(uint8_t*)0x20008ac5 = (uint8_t)0x5; *(uint8_t*)0x20008ac6 = (uint8_t)0x4; *(uint8_t*)0x20008ac7 = (uint8_t)0x4; *(uint8_t*)0x20008ac8 = (uint8_t)0x20; *(uint8_t*)0x20008ac9 = (uint8_t)0x401; *(uint8_t*)0x20008aca = (uint8_t)0x6; *(uint8_t*)0x20008acb = (uint8_t)0x6; *(uint8_t*)0x20008acc = (uint8_t)0x5; *(uint8_t*)0x20008acd = (uint8_t)0x3; *(uint8_t*)0x20008ace = (uint8_t)0xfffffffffffffffc; *(uint8_t*)0x20008acf = (uint8_t)0xb0c; *(uint8_t*)0x20008ad0 = (uint8_t)0x2; *(uint8_t*)0x20008ad1 = (uint8_t)0xfffffffffffffff9; *(uint8_t*)0x20008ad2 = (uint8_t)0x8000; *(uint8_t*)0x20008ad3 = (uint8_t)0x5; *(uint8_t*)0x20008ad4 = (uint8_t)0xb0c; *(uint8_t*)0x20008ad5 = (uint8_t)0xfffffffffffffeff; *(uint8_t*)0x20008ad6 = (uint8_t)0x5; *(uint8_t*)0x20008ad7 = (uint8_t)0x101; *(uint8_t*)0x20008ad8 = (uint8_t)0xbfd; *(uint8_t*)0x20008ad9 = (uint8_t)0x7ff; *(uint8_t*)0x20008ada = (uint8_t)0x7f; *(uint8_t*)0x20008adb = (uint8_t)0x5; *(uint32_t*)0x20008adc = (uint32_t)0x6; *(uint8_t*)0x20008ae0 = (uint8_t)0x0; *(uint8_t*)0x20008ae1 = (uint8_t)0x0; *(uint8_t*)0x20008ae2 = (uint8_t)0x0; *(uint8_t*)0x20008ae3 = (uint8_t)0x0; *(uint8_t*)0x20008ae4 = (uint8_t)0x0; *(uint8_t*)0x20008ae5 = (uint8_t)0x0; *(uint8_t*)0x20008ae6 = (uint8_t)0x0; *(uint8_t*)0x20008ae7 = (uint8_t)0x0; *(uint8_t*)0x20008ae8 = (uint8_t)0x0; *(uint8_t*)0x20008ae9 = (uint8_t)0x0; *(uint8_t*)0x20008aea = (uint8_t)0x0; *(uint8_t*)0x20008aeb = (uint8_t)0x0; *(uint8_t*)0x20008aec = (uint8_t)0x0; *(uint8_t*)0x20008aed = (uint8_t)0x0; *(uint8_t*)0x20008aee = (uint8_t)0x0; *(uint8_t*)0x20008aef = (uint8_t)0x0; *(uint8_t*)0x20008af0 = (uint8_t)0x0; *(uint8_t*)0x20008af1 = (uint8_t)0x0; *(uint8_t*)0x20008af2 = (uint8_t)0x0; *(uint8_t*)0x20008af3 = (uint8_t)0x0; *(uint8_t*)0x20008af4 = (uint8_t)0x0; *(uint8_t*)0x20008af5 = (uint8_t)0x0; *(uint8_t*)0x20008af6 = (uint8_t)0x0; *(uint8_t*)0x20008af7 = (uint8_t)0x0; *(uint8_t*)0x20008af8 = (uint8_t)0x0; *(uint8_t*)0x20008af9 = (uint8_t)0x0; *(uint8_t*)0x20008afa = (uint8_t)0x0; *(uint8_t*)0x20008afb = (uint8_t)0x0; *(uint8_t*)0x20008afc = (uint8_t)0x0; *(uint8_t*)0x20008afd = (uint8_t)0x0; *(uint8_t*)0x20008afe = (uint8_t)0x0; *(uint8_t*)0x20008aff = (uint8_t)0x0; *(uint8_t*)0x20008b00 = (uint8_t)0x0; *(uint8_t*)0x20008b01 = (uint8_t)0x0; *(uint8_t*)0x20008b02 = (uint8_t)0x0; *(uint8_t*)0x20008b03 = (uint8_t)0x0; *(uint8_t*)0x20008b04 = (uint8_t)0x0; *(uint8_t*)0x20008b05 = (uint8_t)0x0; *(uint8_t*)0x20008b06 = (uint8_t)0x0; *(uint8_t*)0x20008b07 = (uint8_t)0x0; *(uint8_t*)0x20008b08 = (uint8_t)0x0; *(uint8_t*)0x20008b09 = (uint8_t)0x0; *(uint8_t*)0x20008b0a = (uint8_t)0x0; *(uint8_t*)0x20008b0b = (uint8_t)0x0; *(uint8_t*)0x20008b0c = (uint8_t)0x0; *(uint8_t*)0x20008b0d = (uint8_t)0x0; *(uint8_t*)0x20008b0e = (uint8_t)0x0; *(uint8_t*)0x20008b0f = (uint8_t)0x0; *(uint8_t*)0x20008b10 = (uint8_t)0x0; *(uint8_t*)0x20008b11 = (uint8_t)0x0; *(uint8_t*)0x20008b12 = (uint8_t)0x0; *(uint8_t*)0x20008b13 = (uint8_t)0x0; *(uint8_t*)0x20008b14 = (uint8_t)0x0; *(uint8_t*)0x20008b15 = (uint8_t)0x0; *(uint8_t*)0x20008b16 = (uint8_t)0x0; *(uint8_t*)0x20008b17 = (uint8_t)0x0; *(uint8_t*)0x20008b18 = (uint8_t)0x0; *(uint8_t*)0x20008b19 = (uint8_t)0x0; *(uint8_t*)0x20008b1a = (uint8_t)0x0; *(uint8_t*)0x20008b1b = (uint8_t)0x0; r[131] = syscall(SYS_ioctl, r[2], 0xc08c5332ul, 0x20008a90ul, 0, 0, 0); break; case 3: *(uint32_t*)0x20009fd0 = (uint32_t)0x30; *(uint32_t*)0x20009fd4 = (uint32_t)0xfff; *(uint64_t*)0x20009fd8 = (uint64_t)0x0; *(uint64_t*)0x20009fe0 = (uint64_t)0x1ce; *(uint64_t*)0x20009fe8 = (uint64_t)0x2; *(uint64_t*)0x20009ff0 = (uint64_t)0xff; *(uint32_t*)0x20009ff8 = (uint32_t)0x10001; r[139] = syscall(SYS_write, r[2], 0x20009fd0ul, 0x30ul, 0, 0, 0); break; case 4: *(uint32_t*)0x2000bb13 = (uint32_t)0x30; *(uint32_t*)0x2000bb17 = (uint32_t)0x2; *(uint64_t*)0x2000bb1b = (uint64_t)0x0; *(uint64_t*)0x2000bb23 = (uint64_t)0x53; *(uint64_t*)0x2000bb2b = (uint64_t)0xfffffffffffffbff; *(uint64_t*)0x2000bb33 = (uint64_t)0x5; *(uint32_t*)0x2000bb3b = (uint32_t)0x5; r[147] = syscall(SYS_write, r[2], 0x2000bb13ul, 0x30ul, 0, 0, 0); break; } return 0; }
int main() { long i; pthread_t th[5];
memset(r, -1, sizeof(r)); for (i = 0; i < 5; i++) { pthread_create(&th[i], 0, thr, (void*)i); usleep(10000); } for (i = 0; i < 5; i++) { pthread_create(&th[i], 0, thr, (void*)i); if (i % 2 == 0) usleep(10000); } usleep(100000); return 0; }
unreferenced object 0xffffc90003663000 (size 24000): comm "a.out", pid 1770, jiffies 4295717383 (age 7.217s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff86644303>] kmemleak_alloc+0x63/0xa0 mm/kmemleak.c:916 [<ffffffff81720da9>] __vmalloc_node_range+0x469/0x640 mm/vmalloc.c:1682 [< inline >] __vmalloc_node mm/vmalloc.c:1710 [< inline >] __vmalloc_node_flags mm/vmalloc.c:1724 [<ffffffff8172104b>] vmalloc+0x5b/0x70 mm/vmalloc.c:1739 [<ffffffff852b92cb>] snd_seq_pool_init+0xbb/0x300 sound/core/seq/seq_memory.c:389 [<ffffffff852b5ff4>] snd_seq_write+0x4d4/0x570 sound/core/seq/seq_clientmgr.c:1029 [<ffffffff817bbfc3>] __vfs_write+0x113/0x4b0 fs/read_write.c:528 [<ffffffff817bda87>] vfs_write+0x167/0x4a0 fs/read_write.c:577 [< inline >] SYSC_write fs/read_write.c:624 [<ffffffff817c0d71>] SyS_write+0x111/0x220 fs/read_write.c:616 [<ffffffff866613f6>] entry_SYSCALL_64_fastpath+0x16/0x7a arch/x86/entry/entry_64.S:185 [<ffffffffffffffff>] 0xffffffffffffffff
On commit 388f7b1d6e8ca06762e2454d28d6c3c55ad0fe95 (4.5-rc3)
Hm, this looks like the issue triggered by concurrent writes to the same client. Does the patch fix the problem?
Yes, it fixes the leak for me.
Tested-by: Dmitry Vyukov dvyukov@google.com
thanks,
Takashi
diff --git a/sound/core/seq/seq_memory.c b/sound/core/seq/seq_memory.c index 801076687bb1..c850345c43b5 100644 --- a/sound/core/seq/seq_memory.c +++ b/sound/core/seq/seq_memory.c @@ -383,15 +383,20 @@ int snd_seq_pool_init(struct snd_seq_pool *pool)
if (snd_BUG_ON(!pool)) return -EINVAL;
if (pool->ptr) /* should be atomic? */return 0;pool->ptr = vmalloc(sizeof(struct snd_seq_event_cell) * pool->size);if (!pool->ptr)
cellptr = vmalloc(sizeof(struct snd_seq_event_cell) * pool->size);if (!cellptr) return -ENOMEM; /* add new cells to the free cell list */ spin_lock_irqsave(&pool->lock, flags);if (pool->ptr) {spin_unlock_irqrestore(&pool->lock, flags);vfree(cellptr);return 0;}pool->ptr = cellptr; pool->free = NULL; for (cell = 0; cell < pool->size; cell++) {