The patch titled Subject: __bitmap_parselist: fix bug in empty string handling has been added to the -mm tree. Its filename is __bitmap_parselist-fix-bug-in-empty-string-handling.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/__bitmap_parselist-fix-bug-in-empty-string-handling.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/__bitmap_parselist-fix-bug-in-empty-string-handling.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Chris Metcalf <cmetcalf@xxxxxxxxxx> Subject: __bitmap_parselist: fix bug in empty string handling bitmap_parselist("", &mask, nmaskbits) will erroneously set bit zero in the mask. The same bug is visible in cpumask_parselist() since it is layered on top of the bitmask code, e.g. if you boot with "isolcpus=", you will actually end up with cpu zero isolated. The bug was introduced in commit 4b060420a596 ("bitmap, irq: add smp_affinity_list interface to /proc/irq") when bitmap_parselist() was generalized to support userspace as well as kernelspace. Fixes: 4b060420a596 ("bitmap, irq: add smp_affinity_list interface to /proc/irq") Signed-off-by: Chris Metcalf <cmetcalf@xxxxxxxxxx> Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/bitmap.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff -puN lib/bitmap.c~__bitmap_parselist-fix-bug-in-empty-string-handling lib/bitmap.c --- a/lib/bitmap.c~__bitmap_parselist-fix-bug-in-empty-string-handling +++ a/lib/bitmap.c @@ -506,12 +506,12 @@ static int __bitmap_parselist(const char unsigned a, b; int c, old_c, totaldigits; const char __user __force *ubuf = (const char __user __force *)buf; - int exp_digit, in_range; + int at_start, in_range; totaldigits = c = 0; bitmap_zero(maskp, nmaskbits); do { - exp_digit = 1; + at_start = 1; in_range = 0; a = b = 0; @@ -540,11 +540,10 @@ static int __bitmap_parselist(const char break; if (c == '-') { - if (exp_digit || in_range) + if (at_start || in_range) return -EINVAL; b = 0; in_range = 1; - exp_digit = 1; continue; } @@ -554,16 +553,18 @@ static int __bitmap_parselist(const char b = b * 10 + (c - '0'); if (!in_range) a = b; - exp_digit = 0; + at_start = 0; totaldigits++; } if (!(a <= b)) return -EINVAL; if (b >= nmaskbits) return -ERANGE; - while (a <= b) { - set_bit(a, maskp); - a++; + if (!at_start) { + while (a <= b) { + set_bit(a, maskp); + a++; + } } } while (buflen && c == ','); return 0; _ Patches currently in -mm which might be from cmetcalf@xxxxxxxxxx are origin.patch __bitmap_parselist-fix-bug-in-empty-string-handling.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html