[v2,2/2] sysvipc: Return EINVAL for invalid shmctl commands
Commit Message
Changes from previous version:
- Handle missing SHM_STAT_ANY on __shmctl64.
--
It avoids regressions on possible future commands that might require
additional libc support. The downside is new commands added by newer
kernels will need further glibc support.
Checked on x86_64-linux-gnu and i686-linux-gnu (Linux v4.15 and v5.4).
---
sysdeps/unix/sysv/linux/shmctl.c | 42 ++++++++++++++++++++++++--------
sysvipc/test-sysvipc.h | 25 +++++++++++++++++++
sysvipc/test-sysvshm.c | 5 ++++
3 files changed, 62 insertions(+), 10 deletions(-)
Comments
On Okt 05 2020, Adhemerval Zanella via Libc-alpha wrote:
> diff --git a/sysvipc/test-sysvipc.h b/sysvipc/test-sysvipc.h
> index 21ef6c6565..179f5e8cc9 100644
> --- a/sysvipc/test-sysvipc.h
> +++ b/sysvipc/test-sysvipc.h
> @@ -107,4 +107,29 @@ first_msg_invalid_cmd (void)
> return invalid;
> }
>
> +/* Return the first invalid command SysV IPC command for shared memory. */
One command too many.
Andreas.
On 05/10/2020 15:35, Andreas Schwab wrote:
> On Okt 05 2020, Adhemerval Zanella via Libc-alpha wrote:
>
>> diff --git a/sysvipc/test-sysvipc.h b/sysvipc/test-sysvipc.h
>> index 21ef6c6565..179f5e8cc9 100644
>> --- a/sysvipc/test-sysvipc.h
>> +++ b/sysvipc/test-sysvipc.h
>> @@ -107,4 +107,29 @@ first_msg_invalid_cmd (void)
>> return invalid;
>> }
>>
>> +/* Return the first invalid command SysV IPC command for shared memory. */
>
> One command too many.
>
> Andreas.
>
Ack, I will rephrase to remove the redundant words.
If no one opposes I will commit this shortly (with Andreas redundant
'command' word in comments).
On 05/10/2020 14:11, Adhemerval Zanella wrote:
> Changes from previous version:
>
> - Handle missing SHM_STAT_ANY on __shmctl64.
>
> --
>
> It avoids regressions on possible future commands that might require
> additional libc support. The downside is new commands added by newer
> kernels will need further glibc support.
>
> Checked on x86_64-linux-gnu and i686-linux-gnu (Linux v4.15 and v5.4).
> ---
> sysdeps/unix/sysv/linux/shmctl.c | 42 ++++++++++++++++++++++++--------
> sysvipc/test-sysvipc.h | 25 +++++++++++++++++++
> sysvipc/test-sysvshm.c | 5 ++++
> 3 files changed, 62 insertions(+), 10 deletions(-)
>
> diff --git a/sysdeps/unix/sysv/linux/shmctl.c b/sysdeps/unix/sysv/linux/shmctl.c
> index 1d19a798b1..73f0b7326f 100644
> --- a/sysdeps/unix/sysv/linux/shmctl.c
> +++ b/sysdeps/unix/sysv/linux/shmctl.c
> @@ -88,25 +88,47 @@ __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf)
> {
> #if __IPC_TIME64
> struct kernel_shmid64_ds kshmid, *arg = NULL;
> - if (buf != NULL)
> +#else
> + shmctl_arg_t *arg;
> +#endif
> +
> + switch (cmd)
> {
> - /* This is a Linux extension where kernel expects either a
> - 'struct shminfo' (IPC_INFO) or 'struct shm_info' (SHM_INFO). */
> - if (cmd == IPC_INFO || cmd == SHM_INFO)
> - arg = (struct kernel_shmid64_ds *) buf;
> - else
> + case IPC_RMID:
> + arg = NULL;
> + break;
> +
> + case IPC_SET:
> + case IPC_STAT:
> + case SHM_STAT:
> + case SHM_STAT_ANY:
> +#if __IPC_TIME64
> + if (buf != NULL)
> {
> shmid64_to_kshmid64 (buf, &kshmid);
> arg = &kshmid;
> }
> - }
> # ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
> - if (cmd == IPC_SET)
> - arg->shm_perm.mode *= 0x10000U;
> + if (cmd == IPC_SET)
> + arg->shm_perm.mode *= 0x10000U;
> # endif
> #else
> - shmctl_arg_t *arg = buf;
> + arg = buf;
> #endif
> + break;
> +
> + case IPC_INFO:
> + case SHM_INFO:
> + /* This is a Linux extension where kernel expects either a
> + 'struct shminfo' (IPC_INFO) or 'struct shm_info' (SHM_INFO). */
> + arg = (__typeof__ (arg)) buf;
> + break;
> +
> + default:
> + __set_errno (EINVAL);
> + return -1;
> + }
> +
>
> int ret = shmctl_syscall (shmid, cmd, arg);
> if (ret < 0)
> diff --git a/sysvipc/test-sysvipc.h b/sysvipc/test-sysvipc.h
> index 21ef6c6565..179f5e8cc9 100644
> --- a/sysvipc/test-sysvipc.h
> +++ b/sysvipc/test-sysvipc.h
> @@ -107,4 +107,29 @@ first_msg_invalid_cmd (void)
> return invalid;
> }
>
> +/* Return the first invalid command SysV IPC command for shared memory. */
> +static inline int
> +first_shm_invalid_cmd (void)
> +{
> + const int shm_cmds[] = {
> + SHM_STAT,
> + SHM_INFO,
> +#ifdef SHM_STAT_ANY
> + SHM_STAT_ANY,
> +#endif
> + };
> +
> + int invalid = first_common_invalid_cmd ();
> + for (int i = 0; i < array_length (shm_cmds); i++)
> + {
> + if (invalid == shm_cmds[i])
> + {
> + invalid++;
> + i = 0;
> + }
> + }
> +
> + return invalid;
> +}
> +
> #endif /* _TEST_SYSV_H */
> diff --git a/sysvipc/test-sysvshm.c b/sysvipc/test-sysvshm.c
> index f083fd280b..a1b8b4823e 100644
> --- a/sysvipc/test-sysvshm.c
> +++ b/sysvipc/test-sysvshm.c
> @@ -25,6 +25,8 @@
> #include <sys/ipc.h>
> #include <sys/shm.h>
>
> +#include <test-sysvipc.h>
> +
> #include <support/support.h>
> #include <support/check.h>
> #include <support/temp_file.h>
> @@ -81,6 +83,9 @@ do_test (void)
> FAIL_EXIT1 ("shmget failed (errno=%d)", errno);
> }
>
> + TEST_COMPARE (shmctl (shmid, first_shm_invalid_cmd (), NULL), -1);
> + TEST_COMPARE (errno, EINVAL);
> +
> /* Get shared memory kernel information and do some sanity checks. */
> struct shmid_ds shminfo;
> if (shmctl (shmid, IPC_STAT, &shminfo) == -1)
>
@@ -88,25 +88,47 @@ __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf)
{
#if __IPC_TIME64
struct kernel_shmid64_ds kshmid, *arg = NULL;
- if (buf != NULL)
+#else
+ shmctl_arg_t *arg;
+#endif
+
+ switch (cmd)
{
- /* This is a Linux extension where kernel expects either a
- 'struct shminfo' (IPC_INFO) or 'struct shm_info' (SHM_INFO). */
- if (cmd == IPC_INFO || cmd == SHM_INFO)
- arg = (struct kernel_shmid64_ds *) buf;
- else
+ case IPC_RMID:
+ arg = NULL;
+ break;
+
+ case IPC_SET:
+ case IPC_STAT:
+ case SHM_STAT:
+ case SHM_STAT_ANY:
+#if __IPC_TIME64
+ if (buf != NULL)
{
shmid64_to_kshmid64 (buf, &kshmid);
arg = &kshmid;
}
- }
# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
- if (cmd == IPC_SET)
- arg->shm_perm.mode *= 0x10000U;
+ if (cmd == IPC_SET)
+ arg->shm_perm.mode *= 0x10000U;
# endif
#else
- shmctl_arg_t *arg = buf;
+ arg = buf;
#endif
+ break;
+
+ case IPC_INFO:
+ case SHM_INFO:
+ /* This is a Linux extension where kernel expects either a
+ 'struct shminfo' (IPC_INFO) or 'struct shm_info' (SHM_INFO). */
+ arg = (__typeof__ (arg)) buf;
+ break;
+
+ default:
+ __set_errno (EINVAL);
+ return -1;
+ }
+
int ret = shmctl_syscall (shmid, cmd, arg);
if (ret < 0)
@@ -107,4 +107,29 @@ first_msg_invalid_cmd (void)
return invalid;
}
+/* Return the first invalid command SysV IPC command for shared memory. */
+static inline int
+first_shm_invalid_cmd (void)
+{
+ const int shm_cmds[] = {
+ SHM_STAT,
+ SHM_INFO,
+#ifdef SHM_STAT_ANY
+ SHM_STAT_ANY,
+#endif
+ };
+
+ int invalid = first_common_invalid_cmd ();
+ for (int i = 0; i < array_length (shm_cmds); i++)
+ {
+ if (invalid == shm_cmds[i])
+ {
+ invalid++;
+ i = 0;
+ }
+ }
+
+ return invalid;
+}
+
#endif /* _TEST_SYSV_H */
@@ -25,6 +25,8 @@
#include <sys/ipc.h>
#include <sys/shm.h>
+#include <test-sysvipc.h>
+
#include <support/support.h>
#include <support/check.h>
#include <support/temp_file.h>
@@ -81,6 +83,9 @@ do_test (void)
FAIL_EXIT1 ("shmget failed (errno=%d)", errno);
}
+ TEST_COMPARE (shmctl (shmid, first_shm_invalid_cmd (), NULL), -1);
+ TEST_COMPARE (errno, EINVAL);
+
/* Get shared memory kernel information and do some sanity checks. */
struct shmid_ds shminfo;
if (shmctl (shmid, IPC_STAT, &shminfo) == -1)