diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2014-04-07 18:38:39 -0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-07 19:36:05 -0400 |
| commit | 23aebe1691a3d98a79676db6c0fd813e16478804 (patch) | |
| tree | bd64954577711239c9a4fe43436f449a529eabcb /fs | |
| parent | 32ed74a4b968a4faff7aaaff557035ce5d5e70ab (diff) | |
exec: kill bprm->tcomm[], simplify the "basename" logic
Starting from commit 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@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/exec.c | 21 |
1 files changed, 2 insertions, 19 deletions
| @@ -1046,7 +1046,7 @@ EXPORT_SYMBOL_GPL(get_task_comm); | |||
| 1046 | * so that a new one can be started | 1046 | * so that a new one can be started |
| 1047 | */ | 1047 | */ |
| 1048 | 1048 | ||
| 1049 | void set_task_comm(struct task_struct *tsk, char *buf) | 1049 | void set_task_comm(struct task_struct *tsk, const char *buf) |
| 1050 | { | 1050 | { |
| 1051 | task_lock(tsk); | 1051 | task_lock(tsk); |
| 1052 | trace_task_rename(tsk, buf); | 1052 | trace_task_rename(tsk, buf); |
| @@ -1055,21 +1055,6 @@ void set_task_comm(struct task_struct *tsk, char *buf) | |||
| 1055 | perf_event_comm(tsk); | 1055 | perf_event_comm(tsk); |
| 1056 | } | 1056 | } |
| 1057 | 1057 | ||
| 1058 | static void filename_to_taskname(char *tcomm, const char *fn, unsigned int len) | ||
| 1059 | { | ||
| 1060 | int i, ch; | ||
| 1061 | |||
| 1062 | /* Copies the binary name from after last slash */ | ||
| 1063 | for (i = 0; (ch = *(fn++)) != '\0';) { | ||
| 1064 | if (ch == '/') | ||
| 1065 | i = 0; /* overwrite what we wrote */ | ||
| 1066 | else | ||
| 1067 | if (i < len - 1) | ||
| 1068 | tcomm[i++] = ch; | ||
| 1069 | } | ||
| 1070 | tcomm[i] = '\0'; | ||
| 1071 | } | ||
| 1072 | |||
| 1073 | int flush_old_exec(struct linux_binprm * bprm) | 1058 | int flush_old_exec(struct linux_binprm * bprm) |
| 1074 | { | 1059 | { |
| 1075 | int retval; | 1060 | int retval; |
| @@ -1083,8 +1068,6 @@ int flush_old_exec(struct linux_binprm * bprm) | |||
| 1083 | goto out; | 1068 | goto out; |
| 1084 | 1069 | ||
| 1085 | set_mm_exe_file(bprm->mm, bprm->file); | 1070 | set_mm_exe_file(bprm->mm, bprm->file); |
| 1086 | |||
| 1087 | filename_to_taskname(bprm->tcomm, bprm->filename, sizeof(bprm->tcomm)); | ||
| 1088 | /* | 1071 | /* |
| 1089 | * Release all of the old mmap stuff | 1072 | * Release all of the old mmap stuff |
| 1090 | */ | 1073 | */ |
| @@ -1127,7 +1110,7 @@ void setup_new_exec(struct linux_binprm * bprm) | |||
| 1127 | else | 1110 | else |
| 1128 | set_dumpable(current->mm, suid_dumpable); | 1111 | set_dumpable(current->mm, suid_dumpable); |
| 1129 | 1112 | ||
| 1130 | set_task_comm(current, bprm->tcomm); | 1113 | set_task_comm(current, kbasename(bprm->filename)); |
| 1131 | 1114 | ||
| 1132 | /* Set the new mm task size. We have to do that late because it may | 1115 | /* Set the new mm task size. We have to do that late because it may |
| 1133 | * depend on TIF_32BIT which is only updated in flush_thread() on | 1116 | * depend on TIF_32BIT which is only updated in flush_thread() on |