| Message ID | 51A6C8FA.3080408@asianux.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
From: Chen Gang <gang.chen@asianux.com> Date: Thu, 30 May 2013 11:35:22 +0800 > > When "cp >= barg_buf + BARG_LEN-2", it breaks internel looping 'while', > but outside loop 'for' still has effect, so "*cp++ = ' '" will continue > repeating which may cause memory overflow. > > So need additional length check for it in the outside looping. > > Also beautify the related code which found by "./scripts/checkpatch.pl" Applied. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 06/19/2013 05:13 PM, David Miller wrote: > From: Chen Gang <gang.chen@asianux.com> > Date: Thu, 30 May 2013 11:35:22 +0800 > >> >> When "cp >= barg_buf + BARG_LEN-2", it breaks internel looping 'while', >> but outside loop 'for' still has effect, so "*cp++ = ' '" will continue >> repeating which may cause memory overflow. >> >> So need additional length check for it in the outside looping. >> >> Also beautify the related code which found by "./scripts/checkpatch.pl" > > Applied. > > Thank you very much.
diff --git a/arch/sparc/prom/bootstr_32.c b/arch/sparc/prom/bootstr_32.c index f5ec32e..d2b49d2 100644 --- a/arch/sparc/prom/bootstr_32.c +++ b/arch/sparc/prom/bootstr_32.c @@ -23,23 +23,25 @@ prom_getbootargs(void) return barg_buf; } - switch(prom_vers) { + switch (prom_vers) { case PROM_V0: cp = barg_buf; /* Start from 1 and go over fd(0,0,0)kernel */ - for(iter = 1; iter < 8; iter++) { + for (iter = 1; iter < 8; iter++) { arg = (*(romvec->pv_v0bootargs))->argv[iter]; if (arg == NULL) break; - while(*arg != 0) { + while (*arg != 0) { /* Leave place for space and null. */ - if(cp >= barg_buf + BARG_LEN-2){ + if (cp >= barg_buf + BARG_LEN - 2) /* We might issue a warning here. */ break; - } *cp++ = *arg++; } *cp++ = ' '; + if (cp >= barg_buf + BARG_LEN - 1) + /* We might issue a warning here. */ + break; } *cp = 0; break;
When "cp >= barg_buf + BARG_LEN-2", it breaks internel looping 'while', but outside loop 'for' still has effect, so "*cp++ = ' '" will continue repeating which may cause memory overflow. So need additional length check for it in the outside looping. Also beautify the related code which found by "./scripts/checkpatch.pl" Signed-off-by: Chen Gang <gang.chen@asianux.com> --- arch/sparc/prom/bootstr_32.c | 12 +++++++----- 1 files changed, 7 insertions(+), 5 deletions(-)