# git rev-parse -q --verify f0a7d1883d9f78ae7bf15fc258bf9a2b20f35b76^{commit} f0a7d1883d9f78ae7bf15fc258bf9a2b20f35b76 already have revision, skipping fetch # git checkout -q -f -B kisskb f0a7d1883d9f78ae7bf15fc258bf9a2b20f35b76 # git clean -qxdf # < git log -1 # commit f0a7d1883d9f78ae7bf15fc258bf9a2b20f35b76 # Author: David Howells # Date: Mon Oct 15 12:43:02 2018 +0100 # # afs: Fix clearance of reply # # The recent patch to fix the afs_server struct leak didn't actually fix the # bug, but rather fixed some of the symptoms. The problem is that an # asynchronous call that holds a resource pointed to by call->reply[0] will # find the pointer cleared in the call destructor, thereby preventing the # resource from being cleaned up. # # In the case of the server record leak, the afs_fs_get_capabilities() # function in devel code sets up a call with reply[0] pointing at the server # record that should be altered when the result is obtained, but this was # being cleared before the destructor was called, so the put in the # destructor does nothing and the record is leaked. # # Commit f014ffb025c1 removed the additional ref obtained by # afs_install_server(), but the removal of this ref is actually used by the # garbage collector to mark a server record as being defunct after the record # has expired through lack of use. # # The offending clearance of call->reply[0] upon completion in # afs_process_async_call() has been there from the origin of the code, but # none of the asynchronous calls actually use that pointer currently, so it # should be safe to remove (note that synchronous calls don't involve this # function). # # Fix this by the following means: # # (1) Revert commit f014ffb025c1. # # (2) Remove the clearance of reply[0] from afs_process_async_call(). # # Without this, afs_manage_servers() will suffer an assertion failure if it # sees a server record that didn't get used because the usage count is not 1. # # Fixes: f014ffb025c1 ("afs: Fix afs_server struct leak") # Fixes: 08e0e7c82eea ("[AF_RXRPC]: Make the in-kernel AFS filesystem use AF_RXRPC.") # Signed-off-by: David Howells # Cc: stable # Signed-off-by: Greg Kroah-Hartman # < /opt/cross/kisskb/arcompact-buildroot-2015.08.1/bin/arc-buildroot-linux-uclibc-gcc --version # < git log --format=%s --max-count=1 f0a7d1883d9f78ae7bf15fc258bf9a2b20f35b76 # < make -s -j 120 ARCH=arc O=/kisskb/build/linus_axs101_defconfig_arcompact CROSS_COMPILE=/opt/cross/kisskb/arcompact-buildroot-2015.08.1/bin/arc-buildroot-linux-uclibc- axs101_defconfig # Added to kconfig CONFIG_INITRAMFS_SOURCE="" # yes \n | make -s -j 120 ARCH=arc O=/kisskb/build/linus_axs101_defconfig_arcompact CROSS_COMPILE=/opt/cross/kisskb/arcompact-buildroot-2015.08.1/bin/arc-buildroot-linux-uclibc- oldconfig yes: standard output: Broken pipe # make -s -j 120 ARCH=arc O=/kisskb/build/linus_axs101_defconfig_arcompact CROSS_COMPILE=/opt/cross/kisskb/arcompact-buildroot-2015.08.1/bin/arc-buildroot-linux-uclibc- In file included from /kisskb/src/include/asm-generic/bug.h:18:0, from /kisskb/src/arch/arc/include/asm/bug.h:32, from /kisskb/src/include/linux/bug.h:5, from /kisskb/src/include/linux/mmdebug.h:5, from /kisskb/src/include/linux/gfp.h:5, from /kisskb/src/include/linux/slab.h:15, from /kisskb/src/mm/nobootmem.c:14: /kisskb/src/mm/nobootmem.c: In function '__free_pages_memory': /kisskb/src/include/linux/kernel.h:845:29: warning: comparison of distinct pointer types lacks a cast [enabled by default] (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) ^ /kisskb/src/include/linux/kernel.h:859:4: note: in expansion of macro '__typecheck' (__typecheck(x, y) && __no_side_effects(x, y)) ^ /kisskb/src/include/linux/kernel.h:869:24: note: in expansion of macro '__safe_cmp' __builtin_choose_expr(__safe_cmp(x, y), \ ^ /kisskb/src/include/linux/kernel.h:878:19: note: in expansion of macro '__careful_cmp' #define min(x, y) __careful_cmp(x, y, <) ^ /kisskb/src/mm/nobootmem.c:104:11: note: in expansion of macro 'min' order = min(MAX_ORDER - 1UL, __ffs(start)); ^ In file included from /kisskb/src/arch/arc/include/asm/atomic.h:16:0, from /kisskb/src/include/linux/atomic.h:7, from /kisskb/src/include/asm-generic/bitops/lock.h:5, from /kisskb/src/arch/arc/include/asm/bitops.h:429, from /kisskb/src/include/linux/bitops.h:19, from /kisskb/src/include/linux/kernel.h:11, from /kisskb/src/include/linux/list.h:9, from /kisskb/src/include/linux/module.h:9, from /kisskb/src/net/core/filter.c:24: /kisskb/src/net/core/filter.c: In function 'bpf_clear_redirect_map': /kisskb/src/arch/arc/include/asm/cmpxchg.h:95:29: warning: value computed is not used [-Wunused-value] #define cmpxchg(ptr, o, n) ((typeof(*(ptr)))__cmpxchg((ptr), \ ^ /kisskb/src/net/core/filter.c:3268:4: note: in expansion of macro 'cmpxchg' cmpxchg(&ri->map, map, NULL); ^ /kisskb/src/net/ipv4/tcp_input.c: In function 'tcp_data_queue': /kisskb/src/net/ipv4/tcp_input.c:4319:49: warning: array subscript is above array bounds [-Warray-bounds] tp->selective_acks[i-1] = tp->selective_acks[i]; ^ Completed OK # rm -rf /kisskb/build/linus_axs101_defconfig_arcompact # Build took: 0:00:21.944292