| Message ID | 1423425729-20671-1-git-send-email-robert.jarzmik@free.fr |
|---|---|
| State | Accepted |
| Commit | e423c90a6520d704cd885d742b499dfd6b0f6277 |
| Headers | show |
On 02/08/2015 05:02 PM, Robert Jarzmik wrote: > As the devicetree binding doesn't require num_cs to exist or be strictly > positive, and neither does the platform data case, a bug appear when > num_cs is set to 0 and panics the kernel. > > The issue is that in alloc_nand_resource(), chip is dereferenced without > having a value assigned when num_cs == 0. > > Fix this by returning ENODEV is num_cs == 0. > > The panic seen is : > Unable to handle kernel NULL pointer dereference at virtual address 000002b8 > pgd = c0004000 > [000002b8] *pgd=00000000 > Internal error: Oops: 5 [#1] PREEMPT ARM > Modules linked in: > Hardware name: Marvell PXA3xx (Device Tree Support) > task: c3822aa0 ti: c3826000 task.ti: c3826000 > PC is at alloc_nand_resource+0x180/0x4a8 > LR is at alloc_nand_resource+0xa0/0x4a8 > pc : [<c0275b90>] lr : [<c0275ab0>] psr: 68000013 > sp : c3827d90 ip : 00000000 fp : 00000000 > r10: c3862200 r9 : 0000005e r8 : 00000000 > r7 : c3865610 r6 : c3862210 r5 : c3924210 r4 : c3862200 > r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : 00000000 > Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel > Control: 0000397f Table: 80004018 DAC: 00000035 > Process swapper (pid: 1, stack limit = 0xc3826198) > Stack: (0xc3827d90 to 0xc3828000) > ...zip... > [<c0275b90>] (alloc_nand_resource) from [<c0275ff8>] (pxa3xx_nand_probe+0x140/0x978) > [<c0275ff8>] (pxa3xx_nand_probe) from [<c0258c40>] (platform_drv_probe+0x48/0xa4) > [<c0258c40>] (platform_drv_probe) from [<c0257650>] (driver_probe_device+0x80/0x21c) > [<c0257650>] (driver_probe_device) from [<c0257878>] (__driver_attach+0x8c/0x90) > [<c0257878>] (__driver_attach) from [<c0255ec4>] (bus_for_each_dev+0x58/0x88) > [<c0255ec4>] (bus_for_each_dev) from [<c0256ec8>] (bus_add_driver+0xd8/0x1d4) > [<c0256ec8>] (bus_add_driver) from [<c0257f14>] (driver_register+0x78/0xf4) > [<c0257f14>] (driver_register) from [<c00088a8>] (do_one_initcall+0x80/0x1e4) > [<c00088a8>] (do_one_initcall) from [<c048ed08>] (kernel_init_freeable+0xec/0x1b4) > [<c048ed08>] (kernel_init_freeable) from [<c0377d8c>] (kernel_init+0x8/0xe4) > [<c0377d8c>] (kernel_init) from [<c00095f8>] (ret_from_fork+0x14/0x3c) > Code: e503b234 e5953008 e1530001 caffffd1 (e59002b8) > ---[ end trace a5770060c8441895 ]--- > > Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> > --- > drivers/mtd/nand/pxa3xx_nand.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c > index 96b0b1d..4a2df63 100644 > --- a/drivers/mtd/nand/pxa3xx_nand.c > +++ b/drivers/mtd/nand/pxa3xx_nand.c > @@ -1572,6 +1572,8 @@ static int alloc_nand_resource(struct platform_device *pdev) > int ret, irq, cs; > > pdata = dev_get_platdata(&pdev->dev); > + if (pdata->num_cs <= 0) > + return -ENODEV; > info = devm_kzalloc(&pdev->dev, sizeof(*info) + (sizeof(*mtd) + > sizeof(*host)) * pdata->num_cs, GFP_KERNEL); > if (!info) > Looks good, Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Ezequiel Garcia <ezequiel.garcia@free-electrons.com> writes: > On 02/08/2015 05:02 PM, Robert Jarzmik wrote: >> As the devicetree binding doesn't require num_cs to exist or be strictly >> positive, and neither does the platform data case, a bug appear when >> num_cs is set to 0 and panics the kernel. ... >> Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> > Looks good, > > Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Brian, David, would queue that up in your for-next tree please ? Cheers.
On Sun, Feb 08, 2015 at 09:02:09PM +0100, Robert Jarzmik wrote: > As the devicetree binding doesn't require num_cs to exist or be strictly > positive, and neither does the platform data case, a bug appear when > num_cs is set to 0 and panics the kernel. > > The issue is that in alloc_nand_resource(), chip is dereferenced without > having a value assigned when num_cs == 0. > > Fix this by returning ENODEV is num_cs == 0. > > The panic seen is : > Unable to handle kernel NULL pointer dereference at virtual address 000002b8 > pgd = c0004000 > [000002b8] *pgd=00000000 > Internal error: Oops: 5 [#1] PREEMPT ARM > Modules linked in: > Hardware name: Marvell PXA3xx (Device Tree Support) > task: c3822aa0 ti: c3826000 task.ti: c3826000 > PC is at alloc_nand_resource+0x180/0x4a8 > LR is at alloc_nand_resource+0xa0/0x4a8 > pc : [<c0275b90>] lr : [<c0275ab0>] psr: 68000013 > sp : c3827d90 ip : 00000000 fp : 00000000 > r10: c3862200 r9 : 0000005e r8 : 00000000 > r7 : c3865610 r6 : c3862210 r5 : c3924210 r4 : c3862200 > r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : 00000000 > Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel > Control: 0000397f Table: 80004018 DAC: 00000035 > Process swapper (pid: 1, stack limit = 0xc3826198) > Stack: (0xc3827d90 to 0xc3828000) > ...zip... > [<c0275b90>] (alloc_nand_resource) from [<c0275ff8>] (pxa3xx_nand_probe+0x140/0x978) > [<c0275ff8>] (pxa3xx_nand_probe) from [<c0258c40>] (platform_drv_probe+0x48/0xa4) > [<c0258c40>] (platform_drv_probe) from [<c0257650>] (driver_probe_device+0x80/0x21c) > [<c0257650>] (driver_probe_device) from [<c0257878>] (__driver_attach+0x8c/0x90) > [<c0257878>] (__driver_attach) from [<c0255ec4>] (bus_for_each_dev+0x58/0x88) > [<c0255ec4>] (bus_for_each_dev) from [<c0256ec8>] (bus_add_driver+0xd8/0x1d4) > [<c0256ec8>] (bus_add_driver) from [<c0257f14>] (driver_register+0x78/0xf4) > [<c0257f14>] (driver_register) from [<c00088a8>] (do_one_initcall+0x80/0x1e4) > [<c00088a8>] (do_one_initcall) from [<c048ed08>] (kernel_init_freeable+0xec/0x1b4) > [<c048ed08>] (kernel_init_freeable) from [<c0377d8c>] (kernel_init+0x8/0xe4) > [<c0377d8c>] (kernel_init) from [<c00095f8>] (ret_from_fork+0x14/0x3c) > Code: e503b234 e5953008 e1530001 caffffd1 (e59002b8) > ---[ end trace a5770060c8441895 ]--- > > Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> Pushed to linux-mtd.git. Thanks. Brian
diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c index 96b0b1d..4a2df63 100644 --- a/drivers/mtd/nand/pxa3xx_nand.c +++ b/drivers/mtd/nand/pxa3xx_nand.c @@ -1572,6 +1572,8 @@ static int alloc_nand_resource(struct platform_device *pdev) int ret, irq, cs; pdata = dev_get_platdata(&pdev->dev); + if (pdata->num_cs <= 0) + return -ENODEV; info = devm_kzalloc(&pdev->dev, sizeof(*info) + (sizeof(*mtd) + sizeof(*host)) * pdata->num_cs, GFP_KERNEL); if (!info)
As the devicetree binding doesn't require num_cs to exist or be strictly positive, and neither does the platform data case, a bug appear when num_cs is set to 0 and panics the kernel. The issue is that in alloc_nand_resource(), chip is dereferenced without having a value assigned when num_cs == 0. Fix this by returning ENODEV is num_cs == 0. The panic seen is : Unable to handle kernel NULL pointer dereference at virtual address 000002b8 pgd = c0004000 [000002b8] *pgd=00000000 Internal error: Oops: 5 [#1] PREEMPT ARM Modules linked in: Hardware name: Marvell PXA3xx (Device Tree Support) task: c3822aa0 ti: c3826000 task.ti: c3826000 PC is at alloc_nand_resource+0x180/0x4a8 LR is at alloc_nand_resource+0xa0/0x4a8 pc : [<c0275b90>] lr : [<c0275ab0>] psr: 68000013 sp : c3827d90 ip : 00000000 fp : 00000000 r10: c3862200 r9 : 0000005e r8 : 00000000 r7 : c3865610 r6 : c3862210 r5 : c3924210 r4 : c3862200 r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 0000397f Table: 80004018 DAC: 00000035 Process swapper (pid: 1, stack limit = 0xc3826198) Stack: (0xc3827d90 to 0xc3828000) ...zip... [<c0275b90>] (alloc_nand_resource) from [<c0275ff8>] (pxa3xx_nand_probe+0x140/0x978) [<c0275ff8>] (pxa3xx_nand_probe) from [<c0258c40>] (platform_drv_probe+0x48/0xa4) [<c0258c40>] (platform_drv_probe) from [<c0257650>] (driver_probe_device+0x80/0x21c) [<c0257650>] (driver_probe_device) from [<c0257878>] (__driver_attach+0x8c/0x90) [<c0257878>] (__driver_attach) from [<c0255ec4>] (bus_for_each_dev+0x58/0x88) [<c0255ec4>] (bus_for_each_dev) from [<c0256ec8>] (bus_add_driver+0xd8/0x1d4) [<c0256ec8>] (bus_add_driver) from [<c0257f14>] (driver_register+0x78/0xf4) [<c0257f14>] (driver_register) from [<c00088a8>] (do_one_initcall+0x80/0x1e4) [<c00088a8>] (do_one_initcall) from [<c048ed08>] (kernel_init_freeable+0xec/0x1b4) [<c048ed08>] (kernel_init_freeable) from [<c0377d8c>] (kernel_init+0x8/0xe4) [<c0377d8c>] (kernel_init) from [<c00095f8>] (ret_from_fork+0x14/0x3c) Code: e503b234 e5953008 e1530001 caffffd1 (e59002b8) ---[ end trace a5770060c8441895 ]--- Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> --- drivers/mtd/nand/pxa3xx_nand.c | 2 ++ 1 file changed, 2 insertions(+)