Subject: + exec-kill-int-depth-in-search_binary_handler.patch added to -mm tree To: oleg@xxxxxxxxxx,keescook@xxxxxxxxxxxx,viro@xxxxxxxxxxxxxxxxxx,zbr@xxxxxxxxxxx,zml@xxxxxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Mon, 05 Aug 2013 13:45:09 -0700 The patch titled Subject: exec: kill "int depth" in search_binary_handler() has been added to the -mm tree. Its filename is exec-kill-int-depth-in-search_binary_handler.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/exec-kill-int-depth-in-search_binary_handler.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/exec-kill-int-depth-in-search_binary_handler.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Oleg Nesterov <oleg@xxxxxxxxxx> Subject: exec: kill "int depth" in search_binary_handler() Nobody except search_binary_handler() should touch ->recursion_depth, "int depth" buys nothing but complicates the code, kill it. Probably we should also kill "fn" and the !NULL check, ->load_binary should be always defined. And it can not go away after read_unlock() or this code is buggy anyway. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Evgeniy Polyakov <zbr@xxxxxxxxxxx> Cc: Zach Levis <zml@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/exec.c | 9 ++++----- include/linux/binfmts.h | 2 +- 2 files changed, 5 insertions(+), 6 deletions(-) diff -puN fs/exec.c~exec-kill-int-depth-in-search_binary_handler fs/exec.c --- a/fs/exec.c~exec-kill-int-depth-in-search_binary_handler +++ a/fs/exec.c @@ -1370,12 +1370,11 @@ EXPORT_SYMBOL(remove_arg_zero); */ int search_binary_handler(struct linux_binprm *bprm) { - unsigned int depth = bprm->recursion_depth; - int try,retval; + int try, retval; struct linux_binfmt *fmt; /* This allows 4 levels of binfmt rewrites before failing hard. */ - if (depth > 5) + if (bprm->recursion_depth > 5) return -ELOOP; retval = security_bprm_check(bprm); @@ -1396,9 +1395,9 @@ int search_binary_handler(struct linux_b if (!try_module_get(fmt->module)) continue; read_unlock(&binfmt_lock); - bprm->recursion_depth = depth + 1; + bprm->recursion_depth++; retval = fn(bprm); - bprm->recursion_depth = depth; + bprm->recursion_depth--; if (retval >= 0) { put_binfmt(fmt); allow_write_access(bprm->file); diff -puN include/linux/binfmts.h~exec-kill-int-depth-in-search_binary_handler include/linux/binfmts.h --- a/include/linux/binfmts.h~exec-kill-int-depth-in-search_binary_handler +++ a/include/linux/binfmts.h @@ -31,7 +31,7 @@ struct linux_binprm { #ifdef __alpha__ unsigned int taso:1; #endif - unsigned int recursion_depth; + unsigned int recursion_depth; /* only for search_binary_handler() */ struct file * file; struct cred *cred; /* new credentials */ int unsafe; /* how unsafe this exec is (mask of LSM_UNSAFE_*) */ _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are x86-get_unmapped_area-use-proper-mmap-base-for-bottom-up-direction.patch include-linux-schedh-dont-use-task-pid-tgid-in-same_thread_group-has_group_leader_pid.patch mm-mempolicy-turn-vma_set_policy-into-vma_dup_policy.patch mm-shift-vm_grows-check-from-mmap_region-to-do_mmap_pgoff-v2.patch mm-do_mmap_pgoff-cleanup-the-usage-of-file_inode.patch mm-mmap_region-kill-correct_wcount-inode-use-allow_write_access.patch kernel-wide-fix-missing-validations-on-__get-__put-__copy_to-__copy_from_user.patch autofs4-allow-autofs-to-work-outside-the-initial-pid-namespace.patch autofs4-translate-pids-to-the-right-namespace-for-the-daemon.patch signals-eventpoll-set-saved_sigmask-at-the-start.patch move-exit_task_namespaces-outside-of-exit_notify-fix.patch exec-introduce-exec_binprm-for-depth-==-0-code.patch exec-kill-int-depth-in-search_binary_handler.patch exec-proc_exec_connector-should-be-called-only-once.patch exec-move-allow_write_access-fput-to-exec_binprm.patch exec-kill-load_binary-=-null-check-in-search_binary_handler.patch exec-cleanup-the-config_modules-logic.patch exec-dont-retry-if-request_module-fails.patch exec-cleanup-the-error-handling-in-search_binary_handler.patch linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html