# git rev-parse -q --verify d41a3effbb53b1bcea41e328d16a4d046a508381^{commit} d41a3effbb53b1bcea41e328d16a4d046a508381 already have revision, skipping fetch # git checkout -q -f -B kisskb d41a3effbb53b1bcea41e328d16a4d046a508381 # git clean -qxdf # < git log -1 # commit d41a3effbb53b1bcea41e328d16a4d046a508381 # Author: Hillf Danton # Date: Mon Sep 2 13:37:29 2019 +0100 # # keys: Fix missing null pointer check in request_key_auth_describe() # # If a request_key authentication token key gets revoked, there's a window in # which request_key_auth_describe() can see it with a NULL payload - but it # makes no check for this and something like the following oops may occur: # # BUG: Kernel NULL pointer dereference at 0x00000038 # Faulting instruction address: 0xc0000000004ddf30 # Oops: Kernel access of bad area, sig: 11 [#1] # ... # NIP [...] request_key_auth_describe+0x90/0xd0 # LR [...] request_key_auth_describe+0x54/0xd0 # Call Trace: # [...] request_key_auth_describe+0x54/0xd0 (unreliable) # [...] proc_keys_show+0x308/0x4c0 # [...] seq_read+0x3d0/0x540 # [...] proc_reg_read+0x90/0x110 # [...] __vfs_read+0x3c/0x70 # [...] vfs_read+0xb4/0x1b0 # [...] ksys_read+0x7c/0x130 # [...] system_call+0x5c/0x70 # # Fix this by checking for a NULL pointer when describing such a key. # # Also make the read routine check for a NULL pointer to be on the safe side. # # [DH: Modified to not take already-held rcu lock and modified to also check # in the read routine] # # Fixes: 04c567d9313e ("[PATCH] Keys: Fix race between two instantiators of a key") # Reported-by: Sachin Sant # Signed-off-by: Hillf Danton # Signed-off-by: David Howells # Tested-by: Sachin Sant # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/gcc-4.6.3-nolibc/m68k-linux/bin/m68k-linux-gcc --version # < /opt/cross/kisskb/gcc-4.6.3-nolibc/m68k-linux/bin/m68k-linux-ld --version # < git log --format=%s --max-count=1 d41a3effbb53b1bcea41e328d16a4d046a508381 # < make -s -j 10 ARCH=m68k O=/kisskb/build/linus_sun3_defconfig_m68k CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/m68k-linux/bin/m68k-linux- sun3_defconfig WARNING: unmet direct dependencies detected for NEED_MULTIPLE_NODES Depends on [n]: DISCONTIGMEM [=n] || NUMA Selected by [y]: - SINGLE_MEMORY_CHUNK [=y] && MMU [=y] WARNING: unmet direct dependencies detected for NEED_MULTIPLE_NODES Depends on [n]: DISCONTIGMEM [=n] || NUMA Selected by [y]: - SINGLE_MEMORY_CHUNK [=y] && MMU [=y] # make -s -j 10 ARCH=m68k O=/kisskb/build/linus_sun3_defconfig_m68k CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/m68k-linux/bin/m68k-linux- :1511:2: warning: #warning syscall clone3 not implemented [-Wcpp] /kisskb/src/ipc/shm.c: In function 'ksys_shmdt': /kisskb/src/ipc/shm.c:1712:59: warning: 'file' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl': /kisskb/src/kernel/printk/printk.c:194:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/cifs/smb2pdu.c: In function 'SMB2_ioctl_init': /kisskb/src/fs/cifs/smb2pdu.c:2676:19: warning: 'in_data_buf' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/lib/mpi/mpicoder.c: In function 'mpi_read_raw_from_sgl': /kisskb/src/lib/mpi/mpicoder.c:336:12: warning: 'buff' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/kernel/acct.c: In function 'acct_pin_kill': /kisskb/src/kernel/acct.c:177:2: warning: value computed is not used [-Wunused-value] /kisskb/src/drivers/md/raid10.c: In function 'read_balance': /kisskb/src/drivers/md/raid10.c:840:22: warning: 'best_pending_slot' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/core/gen_stats.c: In function '__gnet_stats_copy_basic': /kisskb/src/net/core/gen_stats.c:157:19: warning: 'seq' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/core/dev.c: In function 'validate_xmit_skb_list': /kisskb/src/net/core/dev.c:3407:15: warning: 'tail' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/lib/rhashtable.c: In function 'rht_deferred_worker': /kisskb/src/include/linux/rhashtable.h:110:10: warning: 'next' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/lib/rhashtable.c:222:28: note: 'next' was declared here /kisskb/src/net/core/filter.c: In function 'bpf_clear_redirect_map': /kisskb/src/net/core/filter.c:3599:4: warning: value computed is not used [-Wunused-value] /kisskb/src/drivers/net/ethernet/i825xx/sun3_82586.c: In function 'sun3_82586_timeout': /kisskb/src/drivers/net/ethernet/i825xx/sun3_82586.c:993:89: warning: array subscript is above array bounds [-Warray-bounds] /kisskb/src/drivers/net/macsec.c: In function 'macsec_del_rxsa': /kisskb/src/drivers/net/macsec.c:1918:2: warning: 'assoc_num' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/macsec.c:1918:2: warning: 'rx_sc' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/macsec.c: In function 'macsec_del_txsa': /kisskb/src/drivers/net/macsec.c:1995:2: warning: 'assoc_num' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/macsec.c:1995:2: warning: 'tx_sc' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/macsec.c: In function 'macsec_upd_txsa': /kisskb/src/drivers/net/macsec.c:2060:5: warning: 'assoc_num' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/macsec.c:2060:24: warning: 'tx_sc' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/macsec.c:2061:21: warning: 'secy' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c: In function 'tun_get_user': /kisskb/src/drivers/net/tun.c:1834:30: warning: 'copylen' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c:1524:31: warning: 'linear' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c:1747:46: note: 'linear' was declared here /kisskb/src/fs/proc/inode.c: In function 'proc_reg_open': /kisskb/src/include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/proc/inode.c:338:21: note: 'pdeo' was declared here /kisskb/src/fs/ocfs2/alloc.c: In function 'ocfs2_trim_mainbm': /kisskb/src/fs/ocfs2/alloc.c:7590:17: warning: 'first_bit' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/ocfs2/file.c: In function 'ocfs2_file_write_iter': /kisskb/src/fs/ocfs2/file.c:2372:3: warning: value computed is not used [-Wunused-value] /kisskb/src/fs/udf/unicode.c: In function 'udf_name_conv_char': /kisskb/src/fs/udf/unicode.c:132:8: warning: 'c' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/sctp/output.c: In function 'sctp_packet_config': /kisskb/src/include/net/sock.h:1960:19: warning: 'sk' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/sctp/output.c:79:15: note: 'sk' was declared here /kisskb/src/fs/posix_acl.c: In function 'get_acl': /kisskb/src/fs/posix_acl.c:148:3: warning: value computed is not used [-Wunused-value] Completed OK # rm -rf /kisskb/build/linus_sun3_defconfig_m68k # Build took: 0:01:33.746500