[POWERPC] Fix VDSO gettimeofday() when called with NULL struct timeval

Consider the prototype for gettimeofday():
	int gettimofday(struct timeval *tv, struct timezone *tz);

Although it is valid to call with /either/ tv or tz being NULL, and
the C version of sys_gettimeofday() supports this, the current version
of gettimeofday() in the VDSO will SEGV if called with a NULL tv.

This adds a check for tv being NULL so that it doesn't SEGV.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Tony Breeds 2007-06-26 09:50:32 +10:00 committed by Paul Mackerras
parent ca74c01344
commit 74609f4536
2 changed files with 7 additions and 4 deletions

View File

@ -32,6 +32,8 @@ V_FUNCTION_BEGIN(__kernel_gettimeofday)
mr r11,r4 /* r11 saves tz */
bl __get_datapage@local /* get data page */
mr r9, r3 /* datapage ptr in r9 */
cmplwi r10,0 /* check if tv is NULL */
beq 3f
bl __do_get_xsec@local /* get xsec from tb & kernel */
bne- 2f /* out of line -> do syscall */
@ -50,7 +52,7 @@ V_FUNCTION_BEGIN(__kernel_gettimeofday)
mulhwu r5,r5,r6
stw r5,TVAL32_TV_USEC(r10)
cmpli cr0,r11,0 /* check if tz is NULL */
3: cmplwi r11,0 /* check if tz is NULL */
beq 1f
lwz r4,CFG_TZ_MINUTEWEST(r9)/* fill tz */
lwz r5,CFG_TZ_DSTTIME(r9)

View File

@ -1,5 +1,4 @@
/*
/*
* Userland implementation of gettimeofday() for 64 bits processes in a
* ppc64 kernel for use in the vDSO
*
@ -32,6 +31,8 @@ V_FUNCTION_BEGIN(__kernel_gettimeofday)
mr r11,r3 /* r11 holds tv */
mr r10,r4 /* r10 holds tz */
bl V_LOCAL_FUNC(__get_datapage) /* get data page */
cmpldi r10,0 /* check if tv is NULL */
beq 2f
bl V_LOCAL_FUNC(__do_get_xsec) /* get xsec from tb & kernel */
lis r7,15 /* r7 = 1000000 = USEC_PER_SEC */
ori r7,r7,16960
@ -43,8 +44,8 @@ V_FUNCTION_BEGIN(__kernel_gettimeofday)
* XSEC_PER_SEC
*/
rldicl r0,r0,44,20
cmpldi cr0,r10,0 /* check if tz is NULL */
std r0,TVAL64_TV_USEC(r11) /* store usec in tv */
2: cmpldi r10,0 /* check if tz is NULL */
beq 1f
lwz r4,CFG_TZ_MINUTEWEST(r3)/* fill tz */
lwz r5,CFG_TZ_DSTTIME(r3)