| Message ID | 20230320024739.224850-1-mawupeng1@huawei.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Add overflow checks for several syscalls | expand |
Sorry for wasting your time. I send the wrong version of this patchset, this is the older version. I will send the right one later. On 2023/3/20 10:47, Wupeng Ma wrote: > From: Ma Wupeng <mawupeng1@huawei.com> > > While testing mlock, we have a problem if the len of mlock is ULONG_MAX. > The return value of mlock is zero. But nothing will be locked since the > len in do_mlock overflows to zero due to the following code in mlock: > > len = PAGE_ALIGN(len + (offset_in_page(start))); > > The same problem happens in munlock. > > Add new check and return -EINVAL to fix this overflowing scenarios since > they are absolutely wrong. > > Similar logic is used to fix problems with multiple syscalls. > > Here is the testcases: > > #include <stdio.h> > #define _GNU_SOURCE > #include <sys/mman.h> > #include <fcntl.h> > #include <errno.h> > #include <unistd.h> > #include <string.h> > #include <limits.h> > #include <numaif.h> > > extern int errno; > int main(void) > { > int fd; > int ret; > void *addr; > int size = getpagesize(); > > fd = open("/tmp/testfile", O_RDWR | O_CREAT); > if (fd < 0) { > printf("open file error! errno: %d\n", errno); > return -1; > } > printf("open success\n"); > addr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); > if (addr == MAP_FAILED) { > printf("open file error! errno: %d\n", errno); > close(fd); > return -1; > } > printf("mmap success\n"); > memset(addr, 0, size); > > printf("==== mlock ====\n"); > ret = mlock(addr, ULONG_MAX); > if (ret == -1 && errno == EINVAL) > printf("mlock test passed\n"); > else > printf("mlock test failed, ret: %d, errno: %d\n", ret, errno); > > printf("==== set_mempolicy_home_node ====\n"); > ret = syscall(450, addr, ULONG_MAX, 0, 0); > if (ret == -1 && errno == EINVAL) > printf("set_mempolicy_home_node test passed\n"); > else > printf("set_mempolicy_home_node test failed, ret: %d, errno: %d\n", ret, errno); > > printf("==== mbind ====\n"); > unsigned long nodemask = 1Ul << 0; > long max_node = 8 * sizeof(nodemask); > ret = mbind(addr, ULONG_MAX, MPOL_BIND, &nodemask, max_node, MPOL_MF_MOVE_ALL); > if (ret == -1 && errno == EINVAL) > printf("mbind test passed\n"); > else > printf("mbind test failed, ret: %d, errno: %d\n", ret, errno); > > printf("==== msync ====\n"); > ret = msync(addr, ULONG_MAX, MS_ASYNC); > if (ret == -1 && errno == ENOMEM) > printf("mbind test passed\n"); > else > printf("mbind test failed, ret: %d, errno: %d\n", ret, errno); > > munmap(mmap, size); > > return 0; > } > > Changelog since v3[3]: > - rebase to the latest master > - add simple testcases > > Changelog since v2[2]: > - modified the way of checking overflows based on Andrew's comments > > Changelog since v1[1]: > - only check overflow rather than access_ok to keep backward-compatibility > > [1]: https://lore.kernel.org/lkml/20221228141701.c64add46c4b09aa17f605baf@linux-foundation.org/T/ > [2]: https://lore.kernel.org/linux-mm/20230116115813.2956935-5-mawupeng1@huawei.com/T/ > [3]: https://lore.kernel.org/linux-mm/de4149c7-0e6e-2035-3fb8-2f9da9633704@huawei.com/T/ > > Ma Wupeng (4): > mm/mlock: return EINVAL if len overflows for mlock/munlock > mm/mempolicy: return EINVAL for if len overflows for > set_mempolicy_home_node > mm/mempolicy: return EINVAL if len overflows for mbind > mm/msync: return ENOMEM if len overflows for msync > > mm/mempolicy.c | 6 ++++-- > mm/mlock.c | 8 ++++++++ > mm/msync.c | 3 ++- > 3 files changed, 14 insertions(+), 3 deletions(-) >
From: Ma Wupeng <mawupeng1@huawei.com> While testing mlock, we have a problem if the len of mlock is ULONG_MAX. The return value of mlock is zero. But nothing will be locked since the len in do_mlock overflows to zero due to the following code in mlock: len = PAGE_ALIGN(len + (offset_in_page(start))); The same problem happens in munlock. Add new check and return -EINVAL to fix this overflowing scenarios since they are absolutely wrong. Similar logic is used to fix problems with multiple syscalls. Here is the testcases: #include <stdio.h> #define _GNU_SOURCE #include <sys/mman.h> #include <fcntl.h> #include <errno.h> #include <unistd.h> #include <string.h> #include <limits.h> #include <numaif.h> extern int errno; int main(void) { int fd; int ret; void *addr; int size = getpagesize(); fd = open("/tmp/testfile", O_RDWR | O_CREAT); if (fd < 0) { printf("open file error! errno: %d\n", errno); return -1; } printf("open success\n"); addr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (addr == MAP_FAILED) { printf("open file error! errno: %d\n", errno); close(fd); return -1; } printf("mmap success\n"); memset(addr, 0, size); printf("==== mlock ====\n"); ret = mlock(addr, ULONG_MAX); if (ret == -1 && errno == EINVAL) printf("mlock test passed\n"); else printf("mlock test failed, ret: %d, errno: %d\n", ret, errno); printf("==== set_mempolicy_home_node ====\n"); ret = syscall(450, addr, ULONG_MAX, 0, 0); if (ret == -1 && errno == EINVAL) printf("set_mempolicy_home_node test passed\n"); else printf("set_mempolicy_home_node test failed, ret: %d, errno: %d\n", ret, errno); printf("==== mbind ====\n"); unsigned long nodemask = 1Ul << 0; long max_node = 8 * sizeof(nodemask); ret = mbind(addr, ULONG_MAX, MPOL_BIND, &nodemask, max_node, MPOL_MF_MOVE_ALL); if (ret == -1 && errno == EINVAL) printf("mbind test passed\n"); else printf("mbind test failed, ret: %d, errno: %d\n", ret, errno); printf("==== msync ====\n"); ret = msync(addr, ULONG_MAX, MS_ASYNC); if (ret == -1 && errno == ENOMEM) printf("mbind test passed\n"); else printf("mbind test failed, ret: %d, errno: %d\n", ret, errno); munmap(mmap, size); return 0; } Changelog since v3[3]: - rebase to the latest master - add simple testcases Changelog since v2[2]: - modified the way of checking overflows based on Andrew's comments Changelog since v1[1]: - only check overflow rather than access_ok to keep backward-compatibility [1]: https://lore.kernel.org/lkml/20221228141701.c64add46c4b09aa17f605baf@linux-foundation.org/T/ [2]: https://lore.kernel.org/linux-mm/20230116115813.2956935-5-mawupeng1@huawei.com/T/ [3]: https://lore.kernel.org/linux-mm/de4149c7-0e6e-2035-3fb8-2f9da9633704@huawei.com/T/ Ma Wupeng (4): mm/mlock: return EINVAL if len overflows for mlock/munlock mm/mempolicy: return EINVAL for if len overflows for set_mempolicy_home_node mm/mempolicy: return EINVAL if len overflows for mbind mm/msync: return ENOMEM if len overflows for msync mm/mempolicy.c | 6 ++++-- mm/mlock.c | 8 ++++++++ mm/msync.c | 3 ++- 3 files changed, 14 insertions(+), 3 deletions(-)