[PATCH 2/2] treewide: avoid truncation of process name

From: Jan Engelhardt
Date: Sat Jan 21 2012 - 17:09:51 EST


While producing the previous commit, "treewide: fix memory corruptions
when TASK_COMM_LEN != 16", I noticed

1. the process name is truncated for no apparent reason in a number of
places by means of the precision for the %s specifier
(t->comm is always NUL-terminated).
2. padded with an odd size (8) in another
3. redundant instance of: t->tcomm ? t->comm : ""
(t->comm is always non-NULL because it is an array)

Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Steve French <sfrench@xxxxxxxxx>
Signed-off-by: Jan Engelhardt <jengelh@xxxxxxxxxx>
---
arch/x86/kernel/dumpstack.c | 2 +-
arch/x86/kernel/process.c | 2 +-
arch/x86/kernel/process_64.c | 2 +-
kernel/cred.c | 4 ++--
kernel/irq/manage.c | 2 +-
kernel/sched/core.c | 2 +-
net/dns_resolver/internal.h | 2 +-
7 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index 1aae78f..88d1c92 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -185,7 +185,7 @@ void dump_stack(void)
unsigned long stack;

bp = stack_frame(current, NULL);
- printk("Pid: %d, comm: %.20s %s %s %.*s\n",
+ printk("Pid: %d, comm: %s %s %s %.*s\n",
current->pid, current->comm, print_tainted(),
init_utsname()->release,
(int)strcspn(init_utsname()->version, " "),
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 15763af..c7a73ad 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -105,7 +105,7 @@ void show_regs_common(void)
board = dmi_get_system_info(DMI_BOARD_NAME);

printk(KERN_CONT "\n");
- printk(KERN_DEFAULT "Pid: %d, comm: %.20s %s %s %.*s",
+ printk(KERN_DEFAULT "Pid: %d, comm: %s %s %s %.*s",
current->pid, current->comm, print_tainted(),
init_utsname()->release,
(int)strcspn(init_utsname()->version, " "),
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 9b9fe4a..075610b 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -225,7 +225,7 @@ void release_thread(struct task_struct *dead_task)
{
if (dead_task->mm) {
if (dead_task->mm->context.size) {
- printk("WARNING: dead process %8s still has LDT? <%p/%d>\n",
+ printk("WARNING: dead process %s still has LDT? <%p/%d>\n",
dead_task->comm,
dead_task->mm->context.ldt,
dead_task->mm->context.size);
diff --git a/kernel/cred.c b/kernel/cred.c
index 5791612..7f10154 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -20,10 +20,10 @@

#if 0
#define kdebug(FMT, ...) \
- printk("[%-5.5s%5u] "FMT"\n", current->comm, current->pid ,##__VA_ARGS__)
+ printk("[%s/%u] "FMT"\n", current->comm, current->pid ,##__VA_ARGS__)
#else
#define kdebug(FMT, ...) \
- no_printk("[%-5.5s%5u] "FMT"\n", current->comm, current->pid ,##__VA_ARGS__)
+ no_printk("[%s/%u] "FMT"\n", current->comm, current->pid ,##__VA_ARGS__)
#endif

static struct kmem_cache *cred_jar;
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index a9a9dbe..7de16ae 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -838,7 +838,7 @@ void exit_irq_thread(void)

printk(KERN_ERR
"exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
- tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq);
+ tsk->comm, tsk->pid, tsk->irqaction->irq);

desc = irq_to_desc(tsk->irqaction->irq);

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c968185..6caf7cf 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4769,7 +4769,7 @@ void sched_show_task(struct task_struct *p)
unsigned state;

state = p->state ? __ffs(p->state) + 1 : 0;
- printk(KERN_INFO "%-15.15s %c", p->comm,
+ printk(KERN_INFO "%s %c", p->comm,
state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?');
#if BITS_PER_LONG == 32
if (state == TASK_RUNNING)
diff --git a/net/dns_resolver/internal.h b/net/dns_resolver/internal.h
index 189ca9e..8341712 100644
--- a/net/dns_resolver/internal.h
+++ b/net/dns_resolver/internal.h
@@ -36,7 +36,7 @@ extern unsigned dns_resolver_debug;
#define kdebug(FMT, ...) \
do { \
if (unlikely(dns_resolver_debug)) \
- printk(KERN_DEBUG "[%-6.6s] "FMT"\n", \
+ printk(KERN_DEBUG "[%s] "FMT"\n", \
current->comm, ##__VA_ARGS__); \
} while (0)

--
1.7.7

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