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| author | David Daney <david.daney@cavium.com> | 2012-04-05 16:52:13 -0700 |
|---|---|---|
| committer | Grant Likely <grant.likely@secretlab.ca> | 2012-04-10 22:39:16 -0600 |
| commit | 5b7526e3a640e491075557acaa842c59c652c0c3 (patch) | |
| tree | 43b3d5d33078b4683482b25559735e1e5d719a72 /kernel | |
| parent | 0034102808e0dbbf3a2394b82b1bb40b5778de9e (diff) | |
| download | linux-5b7526e3a640e491075557acaa842c59c652c0c3.tar.bz2 | |
irq/irq_domain: Quit ignoring error returns from irq_alloc_desc_from().
In commit 4bbdd45a (irq_domain/powerpc: eliminate irq_map; use
irq_alloc_desc() instead) code was added that ignores error returns
from irq_alloc_desc_from() by (silently) casting the return value to
unsigned. The negitive value error return now suddenly looks like a
valid irq number.
Commits cc79ca69 (irq_domain: Move irq_domain code from powerpc to
kernel/irq) and 1bc04f2c (irq_domain: Add support for base irq and
hwirq in legacy mappings) move this code to its current location in
irqdomain.c
The result of all of this is a null pointer dereference OOPS if one of
the error cases is hit.
The fix: Don't cast away the negativeness of the return value and then
check for errors.
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
[grant.likely: dropped addition of new 'irq' variable]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/irq/irqdomain.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 3601f3fbf67c..9310a8d365b0 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -350,7 +350,8 @@ unsigned int irq_create_direct_mapping(struct irq_domain *domain) unsigned int irq_create_mapping(struct irq_domain *domain, irq_hw_number_t hwirq) { - unsigned int virq, hint; + unsigned int hint; + int virq; pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq); @@ -381,9 +382,9 @@ unsigned int irq_create_mapping(struct irq_domain *domain, if (hint == 0) hint++; virq = irq_alloc_desc_from(hint, 0); - if (!virq) + if (virq <= 0) virq = irq_alloc_desc_from(1, 0); - if (!virq) { + if (virq <= 0) { pr_debug("irq: -> virq allocation failed\n"); return 0; } |