Subject: + exec-kill-bprm-tcomm-simplify-the-basename-logic.patch added to -mm tree To: oleg@xxxxxxxxxx,heiko.carstens@xxxxxxxxxx,rostedt@xxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Wed, 26 Mar 2014 15:40:29 -0700 The patch titled Subject: exec: kill bprm->tcomm[], simplify the "basename" logic has been added to the -mm tree. Its filename is exec-kill-bprm-tcomm-simplify-the-basename-logic.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/exec-kill-bprm-tcomm-simplify-the-basename-logic.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/exec-kill-bprm-tcomm-simplify-the-basename-logic.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 bprm->tcomm[], simplify the "basename" logic Starting from c4ad8f98bef7 ("execve: use 'struct filename *' for executable name passing") bprm->filename can not go away after flush_old_exec(), so we do not need to save the binary name in bprm->tcomm[] added by 96e02d158678 ("exec: fix use-after-free bug in setup_new_exec()"). And there was never need for filename_to_taskname-like code, we can simply do set_task_comm(kbasename(filename). This patch has to change set_task_comm() and trace_task_rename() to accept "const char *", but I think this change is also good. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/exec.c | 21 ++------------------- include/linux/binfmts.h | 1 - include/linux/sched.h | 2 +- include/trace/events/task.h | 2 +- 4 files changed, 4 insertions(+), 22 deletions(-) diff -puN fs/exec.c~exec-kill-bprm-tcomm-simplify-the-basename-logic fs/exec.c --- a/fs/exec.c~exec-kill-bprm-tcomm-simplify-the-basename-logic +++ a/fs/exec.c @@ -1046,7 +1046,7 @@ EXPORT_SYMBOL_GPL(get_task_comm); * so that a new one can be started */ -void set_task_comm(struct task_struct *tsk, char *buf) +void set_task_comm(struct task_struct *tsk, const char *buf) { task_lock(tsk); trace_task_rename(tsk, buf); @@ -1055,21 +1055,6 @@ void set_task_comm(struct task_struct *t perf_event_comm(tsk); } -static void filename_to_taskname(char *tcomm, const char *fn, unsigned int len) -{ - int i, ch; - - /* Copies the binary name from after last slash */ - for (i = 0; (ch = *(fn++)) != '\0';) { - if (ch == '/') - i = 0; /* overwrite what we wrote */ - else - if (i < len - 1) - tcomm[i++] = ch; - } - tcomm[i] = '\0'; -} - int flush_old_exec(struct linux_binprm * bprm) { int retval; @@ -1083,8 +1068,6 @@ int flush_old_exec(struct linux_binprm * goto out; set_mm_exe_file(bprm->mm, bprm->file); - - filename_to_taskname(bprm->tcomm, bprm->filename, sizeof(bprm->tcomm)); /* * Release all of the old mmap stuff */ @@ -1127,7 +1110,7 @@ void setup_new_exec(struct linux_binprm else set_dumpable(current->mm, suid_dumpable); - set_task_comm(current, bprm->tcomm); + set_task_comm(current, kbasename(bprm->filename)); /* Set the new mm task size. We have to do that late because it may * depend on TIF_32BIT which is only updated in flush_thread() on diff -puN include/linux/binfmts.h~exec-kill-bprm-tcomm-simplify-the-basename-logic include/linux/binfmts.h --- a/include/linux/binfmts.h~exec-kill-bprm-tcomm-simplify-the-basename-logic +++ a/include/linux/binfmts.h @@ -44,7 +44,6 @@ struct linux_binprm { unsigned interp_flags; unsigned interp_data; unsigned long loader, exec; - char tcomm[TASK_COMM_LEN]; }; #define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0 diff -puN include/linux/sched.h~exec-kill-bprm-tcomm-simplify-the-basename-logic include/linux/sched.h --- a/include/linux/sched.h~exec-kill-bprm-tcomm-simplify-the-basename-logic +++ a/include/linux/sched.h @@ -2325,7 +2325,7 @@ extern long do_fork(unsigned long, unsig struct task_struct *fork_idle(int); extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); -extern void set_task_comm(struct task_struct *tsk, char *from); +extern void set_task_comm(struct task_struct *tsk, const char *from); extern char *get_task_comm(char *to, struct task_struct *tsk); #ifdef CONFIG_SMP diff -puN include/trace/events/task.h~exec-kill-bprm-tcomm-simplify-the-basename-logic include/trace/events/task.h --- a/include/trace/events/task.h~exec-kill-bprm-tcomm-simplify-the-basename-logic +++ a/include/trace/events/task.h @@ -32,7 +32,7 @@ TRACE_EVENT(task_newtask, TRACE_EVENT(task_rename, - TP_PROTO(struct task_struct *task, char *comm), + TP_PROTO(struct task_struct *task, const char *comm), TP_ARGS(task, comm), _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are kthread-ensure-locality-of-task_struct-allocations.patch mm-revert-thp-make-madv_hugepage-check-for-mm-def_flags.patch mm-revert-thp-make-madv_hugepage-check-for-mm-def_flags-ignore-madv_hugepage-on-s390-to-prevent-sigsegv-in-qemu.patch mm-thp-add-vm_init_def_mask-and-prctl_thp_disable.patch exec-kill-the-unnecessary-mm-def_flags-setting-in-load_elf_binary.patch mm-per-thread-vma-caching.patch mm-per-thread-vma-caching-fix-4.patch mm-per-thread-vma-caching-fix-6.patch mm-per-thread-vma-caching-fix-6-fix.patch fork-collapse-copy_flags-into-copy_process.patch mm-mempolicy-rename-slab_node-for-clarity.patch mm-mempolicy-remove-per-process-flag.patch res_counter-remove-interface-for-locked-charging-and-uncharging.patch exit-call-disassociate_ctty-before-exit_task_namespaces.patch exit-move-check_stack_usage-to-the-end-of-do_exit.patch exitc-call-proc_exit_connector-after-exit_state-is-set.patch proc-show-mnt_id-in-proc-pid-fdinfo.patch exec-kill-bprm-tcomm-simplify-the-basename-logic.patch wait-fix-reparent_leader-vs-exit_dead-exit_zombie-race.patch wait-introduce-exit_trace-to-avoid-the-racy-exit_dead-exit_zombie-transition.patch wait-use-exit_trace-only-if-thread_group_leaderzombie.patch wait-completely-ignore-the-exit_dead-tasks.patch wait-swap-exit_zombie-and-exit_dead-to-hide-exit_trace-from-user-space.patch wait-wstoppedwcontinued-hangs-if-a-zombie-child-is-traced-by-real_parent.patch wait-wstoppedwcontinued-doesnt-work-if-a-zombie-leader-is-traced-by-another-process.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