tree: https://github.com/ceph/ceph-client.git testing head: 3fef7c3fd10c5f078e0f6ec8c683f2d1e14eb05d commit: 3fef7c3fd10c5f078e0f6ec8c683f2d1e14eb05d [77/77] ceph: fix potential use-after-free bug when trimming caps config: x86_64-randconfig-a011-20230417 (https://download.01.org/0day-ci/archive/20230417/202304172343.2ToBO5ag-lkp@xxxxxxxxx/config) compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/ceph/ceph-client/commit/3fef7c3fd10c5f078e0f6ec8c683f2d1e14eb05d git remote add ceph-client https://github.com/ceph/ceph-client.git git fetch --no-tags ceph-client testing git checkout 3fef7c3fd10c5f078e0f6ec8c683f2d1e14eb05d # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash fs/ceph/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Link: https://lore.kernel.org/oe-kbuild-all/202304172343.2ToBO5ag-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> fs/ceph/mds_client.c:1866:6: warning: variable 'iputs' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] if (cap) { ^~~ fs/ceph/mds_client.c:1877:9: note: uninitialized use occurs here while (iputs--) ^~~~~ fs/ceph/mds_client.c:1866:2: note: remove the 'if' if its condition is always true if (cap) { ^~~~~~~~~ fs/ceph/mds_client.c:1862:11: note: initialize the variable 'iputs' to silence this warning int iputs; ^ = 0 >> fs/ceph/mds_client.c:1957:7: warning: variable 'cap' is uninitialized when used here [-Wuninitialized] if (cap->cap_gen < atomic_read(&cap->session->s_cap_gen)) { ^~~ fs/ceph/mds_client.c:1949:22: note: initialize the variable 'cap' to silence this warning struct ceph_cap *cap; ^ = NULL 2 warnings generated. vim +1866 fs/ceph/mds_client.c 1855 1856 static int remove_session_caps_cb(struct inode *inode, struct rb_node *ci_node, 1857 void *arg) 1858 { 1859 struct ceph_inode_info *ci = ceph_inode(inode); 1860 bool invalidate = false; 1861 struct ceph_cap *cap; 1862 int iputs; 1863 1864 spin_lock(&ci->i_ceph_lock); 1865 cap = rb_entry(ci_node, struct ceph_cap, ci_node); > 1866 if (cap) { 1867 dout(" removing cap %p, ci is %p, inode is %p\n", 1868 cap, ci, &ci->netfs.inode); 1869 1870 iputs = ceph_purge_inode_cap(inode, cap, &invalidate); 1871 } 1872 spin_unlock(&ci->i_ceph_lock); 1873 1874 wake_up_all(&ci->i_cap_wq); 1875 if (invalidate) 1876 ceph_queue_invalidate(inode); 1877 while (iputs--) 1878 iput(inode); 1879 return 0; 1880 } 1881 1882 /* 1883 * caller must hold session s_mutex 1884 */ 1885 static void remove_session_caps(struct ceph_mds_session *session) 1886 { 1887 struct ceph_fs_client *fsc = session->s_mdsc->fsc; 1888 struct super_block *sb = fsc->sb; 1889 LIST_HEAD(dispose); 1890 1891 dout("remove_session_caps on %p\n", session); 1892 ceph_iterate_session_caps(session, remove_session_caps_cb, fsc); 1893 1894 wake_up_all(&fsc->mdsc->cap_flushing_wq); 1895 1896 spin_lock(&session->s_cap_lock); 1897 if (session->s_nr_caps > 0) { 1898 struct inode *inode; 1899 struct ceph_cap *cap, *prev = NULL; 1900 struct ceph_vino vino; 1901 /* 1902 * iterate_session_caps() skips inodes that are being 1903 * deleted, we need to wait until deletions are complete. 1904 * __wait_on_freeing_inode() is designed for the job, 1905 * but it is not exported, so use lookup inode function 1906 * to access it. 1907 */ 1908 while (!list_empty(&session->s_caps)) { 1909 cap = list_entry(session->s_caps.next, 1910 struct ceph_cap, session_caps); 1911 if (cap == prev) 1912 break; 1913 prev = cap; 1914 vino = cap->ci->i_vino; 1915 spin_unlock(&session->s_cap_lock); 1916 1917 inode = ceph_find_inode(sb, vino); 1918 iput(inode); 1919 1920 spin_lock(&session->s_cap_lock); 1921 } 1922 } 1923 1924 // drop cap expires and unlock s_cap_lock 1925 detach_cap_releases(session, &dispose); 1926 1927 BUG_ON(session->s_nr_caps > 0); 1928 BUG_ON(!list_empty(&session->s_cap_flushing)); 1929 spin_unlock(&session->s_cap_lock); 1930 dispose_cap_releases(session->s_mdsc, &dispose); 1931 } 1932 1933 enum { 1934 RECONNECT, 1935 RENEWCAPS, 1936 FORCE_RO, 1937 }; 1938 1939 /* 1940 * wake up any threads waiting on this session's caps. if the cap is 1941 * old (didn't get renewed on the client reconnect), remove it now. 1942 * 1943 * caller must hold s_mutex. 1944 */ 1945 static int wake_up_session_cb(struct inode *inode, struct rb_node *ci_node, void *arg) 1946 { 1947 struct ceph_inode_info *ci = ceph_inode(inode); 1948 unsigned long ev = (unsigned long)arg; 1949 struct ceph_cap *cap; 1950 1951 if (ev == RECONNECT) { 1952 spin_lock(&ci->i_ceph_lock); 1953 ci->i_wanted_max_size = 0; 1954 ci->i_requested_max_size = 0; 1955 spin_unlock(&ci->i_ceph_lock); 1956 } else if (ev == RENEWCAPS) { > 1957 if (cap->cap_gen < atomic_read(&cap->session->s_cap_gen)) { 1958 /* mds did not re-issue stale cap */ 1959 spin_lock(&ci->i_ceph_lock); 1960 cap = rb_entry(ci_node, struct ceph_cap, ci_node); 1961 if (cap) 1962 cap->issued = cap->implemented = CEPH_CAP_PIN; 1963 spin_unlock(&ci->i_ceph_lock); 1964 } 1965 } else if (ev == FORCE_RO) { 1966 } 1967 wake_up_all(&ci->i_cap_wq); 1968 return 0; 1969 } 1970 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
