| Message ID | 20241015152602.184108-1-zhengzengkai@huawei.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | [v3] ACPI: GTDT: Tighten the check for the array of platform timer structures | expand |
On Tue, Oct 15, 2024 at 11:26:02PM +0800, Zheng Zengkai wrote: > As suggested by Marc and Lorenzo, first we need to check whether the I would just describe the change, the tags and Link: are there to describe this patch history. > platform_timer entry pointer is within gtdt bounds (< gtdt_end) before > de-referencing what it points at to detect the length of the platform > timer struct and then check that the length of current platform_timer > struct is also valid, i.e. the length is not zero and within gtdt_end. > Now next_platform_timer() only checks against gtdt_end for the entry of > subsequent platform timer without checking the length of it and will > not report error if the check failed and the existing check in function > acpi_gtdt_init() is also not enough. > > Modify the for_each_platform_timer() iterator and use it combined with > a dedicated check function platform_timer_valid() to do the check > against table length (gtdt_end) for each element of platform timer > array in function acpi_gtdt_init(), making sure that both their entry > and length actually fit in the table. > > Suggested-by: Lorenzo Pieralisi <lpieralisi@kernel.org> > Co-developed-by: Marc Zyngier <maz@kernel.org> > Signed-off-by: Marc Zyngier <maz@kernel.org> > Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> > --- > Changes in v3: > - based on Marc's patch and reuse the for_each_platform_timer() loop > > Changes in v2: > - Check against gtdt_end for both entry and len of each array element > Link to v2: https://lore.kernel.org/linux-arm-kernel/20241012085343.6594-1-zhengzengkai@huawei.com/ > > Link to v1: https://lore.kernel.org/all/20241010144703.113728-1-zhengzengkai@huawei.com/ > --- > drivers/acpi/arm64/gtdt.c | 32 +++++++++++++++++++++----------- > 1 file changed, 21 insertions(+), 11 deletions(-) > > diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c > index c0e77c1c8e09..3583c99afb0d 100644 > --- a/drivers/acpi/arm64/gtdt.c > +++ b/drivers/acpi/arm64/gtdt.c > @@ -36,19 +36,25 @@ struct acpi_gtdt_descriptor { > > static struct acpi_gtdt_descriptor acpi_gtdt_desc __initdata; > > -static inline __init void *next_platform_timer(void *platform_timer) > +static __init bool platform_timer_valid(void *platform_timer) > { > struct acpi_gtdt_header *gh = platform_timer; > > - platform_timer += gh->length; > - if (platform_timer < acpi_gtdt_desc.gtdt_end) > - return platform_timer; > + return (platform_timer >= (void *)(acpi_gtdt_desc.gtdt + 1) && > + platform_timer < acpi_gtdt_desc.gtdt_end && > + gh->length != 0 && > + platform_timer + gh->length <= acpi_gtdt_desc.gtdt_end); > +} > + > +static __init void *next_platform_timer(void *platform_timer) > +{ > + struct acpi_gtdt_header *gh = platform_timer; > > - return NULL; > + return platform_timer + gh->length; > } > > -#define for_each_platform_timer(_g) \ > - for (_g = acpi_gtdt_desc.platform_timer; _g; \ > +#define for_each_platform_timer(_g, first_entry) \ > + for (_g = first_entry; platform_timer_valid(_g); \ > _g = next_platform_timer(_g)) > > static inline bool is_timer_block(void *platform_timer) > @@ -155,8 +161,9 @@ bool __init acpi_gtdt_c3stop(int type) > int __init acpi_gtdt_init(struct acpi_table_header *table, > int *platform_timer_count) > { > - void *platform_timer; > + void *platform_timer, *tmp; It makes more sense - thank you and Marc. Nit: you don't really need another pointer (ie tmp) but you may keep it if that makes the code clearer - all you need to do is using platform_timer as an iterator and initialize acpi_gtdt_desc.platform_timer = (void *)gtdt + gtdt->platform_timer_offset; if all checks passed (you are using tmp just because after the loop platform_timer can't be used to initialize acpi_gtdt_desc.platform_timer). Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org> (now let's see if this survives GTDTs out there :)) > struct acpi_table_gtdt *gtdt; > + int cnt = 0; > > gtdt = container_of(table, struct acpi_table_gtdt, header); > acpi_gtdt_desc.gtdt = gtdt; > @@ -177,7 +184,10 @@ int __init acpi_gtdt_init(struct acpi_table_header *table, > } > > platform_timer = (void *)gtdt + gtdt->platform_timer_offset; > - if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) { > + for_each_platform_timer(tmp, platform_timer) > + cnt++; > + > + if (cnt != gtdt->platform_timer_count) { > pr_err(FW_BUG "invalid timer data.\n"); > return -EINVAL; > } > @@ -305,7 +315,7 @@ int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, > void *platform_timer; > > *timer_count = 0; > - for_each_platform_timer(platform_timer) { > + for_each_platform_timer(platform_timer, acpi_gtdt_desc.platform_timer) { > if (is_timer_block(platform_timer)) { > ret = gtdt_parse_timer_block(platform_timer, timer_mem); > if (ret) > @@ -398,7 +408,7 @@ static int __init gtdt_sbsa_gwdt_init(void) > if (ret || !timer_count) > goto out_put_gtdt; > > - for_each_platform_timer(platform_timer) { > + for_each_platform_timer(platform_timer, acpi_gtdt_desc.platform_timer) { > if (is_non_secure_watchdog(platform_timer)) { > ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); > if (ret) > -- > 2.20.1 >
Hi Lorenzo, 在 2024/10/16 0:44, Lorenzo Pieralisi 写道: > On Tue, Oct 15, 2024 at 11:26:02PM +0800, Zheng Zengkai wrote: >> As suggested by Marc and Lorenzo, first we need to check whether the > I would just describe the change, the tags and Link: are there to > describe this patch history. Do you mean that the previous patch below also need to be listed in this change log history? https://lore.kernel.org/all/20240930030716.179992-1-zhengzengkai@huawei.com/ >> platform_timer entry pointer is within gtdt bounds (< gtdt_end) before >> de-referencing what it points at to detect the length of the platform >> timer struct and then check that the length of current platform_timer >> struct is also valid, i.e. the length is not zero and within gtdt_end. >> Now next_platform_timer() only checks against gtdt_end for the entry of >> subsequent platform timer without checking the length of it and will >> not report error if the check failed and the existing check in function >> acpi_gtdt_init() is also not enough. >> >> Modify the for_each_platform_timer() iterator and use it combined with >> a dedicated check function platform_timer_valid() to do the check >> against table length (gtdt_end) for each element of platform timer >> array in function acpi_gtdt_init(), making sure that both their entry >> and length actually fit in the table. >> >> Suggested-by: Lorenzo Pieralisi <lpieralisi@kernel.org> >> Co-developed-by: Marc Zyngier <maz@kernel.org> >> Signed-off-by: Marc Zyngier <maz@kernel.org> >> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> >> --- >> Changes in v3: >> - based on Marc's patch and reuse the for_each_platform_timer() loop >> >> Changes in v2: >> - Check against gtdt_end for both entry and len of each array element >> Link to v2: https://lore.kernel.org/linux-arm-kernel/20241012085343.6594-1-zhengzengkai@huawei.com/ >> >> Link to v1: https://lore.kernel.org/all/20241010144703.113728-1-zhengzengkai@huawei.com/ >> --- >> drivers/acpi/arm64/gtdt.c | 32 +++++++++++++++++++++----------- >> 1 file changed, 21 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c >> index c0e77c1c8e09..3583c99afb0d 100644 >> --- a/drivers/acpi/arm64/gtdt.c >> +++ b/drivers/acpi/arm64/gtdt.c >> @@ -36,19 +36,25 @@ struct acpi_gtdt_descriptor { >> >> static struct acpi_gtdt_descriptor acpi_gtdt_desc __initdata; >> >> -static inline __init void *next_platform_timer(void *platform_timer) >> +static __init bool platform_timer_valid(void *platform_timer) >> { >> struct acpi_gtdt_header *gh = platform_timer; >> >> - platform_timer += gh->length; >> - if (platform_timer < acpi_gtdt_desc.gtdt_end) >> - return platform_timer; >> + return (platform_timer >= (void *)(acpi_gtdt_desc.gtdt + 1) && >> + platform_timer < acpi_gtdt_desc.gtdt_end && >> + gh->length != 0 && >> + platform_timer + gh->length <= acpi_gtdt_desc.gtdt_end); >> +} >> + >> +static __init void *next_platform_timer(void *platform_timer) >> +{ >> + struct acpi_gtdt_header *gh = platform_timer; >> >> - return NULL; >> + return platform_timer + gh->length; >> } >> >> -#define for_each_platform_timer(_g) \ >> - for (_g = acpi_gtdt_desc.platform_timer; _g; \ >> +#define for_each_platform_timer(_g, first_entry) \ >> + for (_g = first_entry; platform_timer_valid(_g); \ >> _g = next_platform_timer(_g)) >> >> static inline bool is_timer_block(void *platform_timer) >> @@ -155,8 +161,9 @@ bool __init acpi_gtdt_c3stop(int type) >> int __init acpi_gtdt_init(struct acpi_table_header *table, >> int *platform_timer_count) >> { >> - void *platform_timer; >> + void *platform_timer, *tmp; > It makes more sense - thank you and Marc. > > Nit: you don't really need another pointer (ie tmp) but you may keep > it if that makes the code clearer - all you need to do is using > platform_timer as an iterator and initialize Yes, the tmp pointer can be removed for conciseness. Thanks! > > acpi_gtdt_desc.platform_timer = (void *)gtdt + gtdt->platform_timer_offset; > > if all checks passed (you are using tmp just because after the loop > platform_timer can't be used to initialize acpi_gtdt_desc.platform_timer). > > Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org> > > (now let's see if this survives GTDTs out there :)) >> struct acpi_table_gtdt *gtdt; >> + int cnt = 0; >> >> gtdt = container_of(table, struct acpi_table_gtdt, header); >> acpi_gtdt_desc.gtdt = gtdt; >> @@ -177,7 +184,10 @@ int __init acpi_gtdt_init(struct acpi_table_header *table, >> } >> >> platform_timer = (void *)gtdt + gtdt->platform_timer_offset; >> - if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) { >> + for_each_platform_timer(tmp, platform_timer) >> + cnt++; >> + >> + if (cnt != gtdt->platform_timer_count) { >> pr_err(FW_BUG "invalid timer data.\n"); >> return -EINVAL; >> } >> @@ -305,7 +315,7 @@ int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, >> void *platform_timer; >> >> *timer_count = 0; >> - for_each_platform_timer(platform_timer) { >> + for_each_platform_timer(platform_timer, acpi_gtdt_desc.platform_timer) { >> if (is_timer_block(platform_timer)) { >> ret = gtdt_parse_timer_block(platform_timer, timer_mem); >> if (ret) >> @@ -398,7 +408,7 @@ static int __init gtdt_sbsa_gwdt_init(void) >> if (ret || !timer_count) >> goto out_put_gtdt; >> >> - for_each_platform_timer(platform_timer) { >> + for_each_platform_timer(platform_timer, acpi_gtdt_desc.platform_timer) { >> if (is_non_secure_watchdog(platform_timer)) { >> ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); >> if (ret) >> -- >> 2.20.1 >> > . >
On Wed, Oct 16, 2024 at 04:49:36PM +0800, Zheng Zengkai wrote: > Hi Lorenzo, > > 在 2024/10/16 0:44, Lorenzo Pieralisi 写道: > > On Tue, Oct 15, 2024 at 11:26:02PM +0800, Zheng Zengkai wrote: > > > As suggested by Marc and Lorenzo, first we need to check whether the > > I would just describe the change, the tags and Link: are there to > > describe this patch history. > > > Do you mean that the previous patch below also need to be listed in this > change log history? > > https://lore.kernel.org/all/20240930030716.179992-1-zhengzengkai@huawei.com/ No, it was just a comment referring to "As suggested by Marc and Lorenzo", that's clear from the tags and a Link: to this thread will be added when the patch is applied (though you can add it too, it would not hurt). Never mind. Lorenzo > > > platform_timer entry pointer is within gtdt bounds (< gtdt_end) before > > > de-referencing what it points at to detect the length of the platform > > > timer struct and then check that the length of current platform_timer > > > struct is also valid, i.e. the length is not zero and within gtdt_end. > > > Now next_platform_timer() only checks against gtdt_end for the entry of > > > subsequent platform timer without checking the length of it and will > > > not report error if the check failed and the existing check in function > > > acpi_gtdt_init() is also not enough. > > > > > > Modify the for_each_platform_timer() iterator and use it combined with > > > a dedicated check function platform_timer_valid() to do the check > > > against table length (gtdt_end) for each element of platform timer > > > array in function acpi_gtdt_init(), making sure that both their entry > > > and length actually fit in the table. > > > > > > Suggested-by: Lorenzo Pieralisi <lpieralisi@kernel.org> > > > Co-developed-by: Marc Zyngier <maz@kernel.org> > > > Signed-off-by: Marc Zyngier <maz@kernel.org> > > > Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> > > > --- > > > Changes in v3: > > > - based on Marc's patch and reuse the for_each_platform_timer() loop > > > > > > Changes in v2: > > > - Check against gtdt_end for both entry and len of each array element > > > Link to v2: https://lore.kernel.org/linux-arm-kernel/20241012085343.6594-1-zhengzengkai@huawei.com/ > > > > > > Link to v1: https://lore.kernel.org/all/20241010144703.113728-1-zhengzengkai@huawei.com/ > > > --- > > > drivers/acpi/arm64/gtdt.c | 32 +++++++++++++++++++++----------- > > > 1 file changed, 21 insertions(+), 11 deletions(-) > > > > > > diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c > > > index c0e77c1c8e09..3583c99afb0d 100644 > > > --- a/drivers/acpi/arm64/gtdt.c > > > +++ b/drivers/acpi/arm64/gtdt.c > > > @@ -36,19 +36,25 @@ struct acpi_gtdt_descriptor { > > > static struct acpi_gtdt_descriptor acpi_gtdt_desc __initdata; > > > -static inline __init void *next_platform_timer(void *platform_timer) > > > +static __init bool platform_timer_valid(void *platform_timer) > > > { > > > struct acpi_gtdt_header *gh = platform_timer; > > > - platform_timer += gh->length; > > > - if (platform_timer < acpi_gtdt_desc.gtdt_end) > > > - return platform_timer; > > > + return (platform_timer >= (void *)(acpi_gtdt_desc.gtdt + 1) && > > > + platform_timer < acpi_gtdt_desc.gtdt_end && > > > + gh->length != 0 && > > > + platform_timer + gh->length <= acpi_gtdt_desc.gtdt_end); > > > +} > > > + > > > +static __init void *next_platform_timer(void *platform_timer) > > > +{ > > > + struct acpi_gtdt_header *gh = platform_timer; > > > - return NULL; > > > + return platform_timer + gh->length; > > > } > > > -#define for_each_platform_timer(_g) \ > > > - for (_g = acpi_gtdt_desc.platform_timer; _g; \ > > > +#define for_each_platform_timer(_g, first_entry) \ > > > + for (_g = first_entry; platform_timer_valid(_g); \ > > > _g = next_platform_timer(_g)) > > > static inline bool is_timer_block(void *platform_timer) > > > @@ -155,8 +161,9 @@ bool __init acpi_gtdt_c3stop(int type) > > > int __init acpi_gtdt_init(struct acpi_table_header *table, > > > int *platform_timer_count) > > > { > > > - void *platform_timer; > > > + void *platform_timer, *tmp; > > It makes more sense - thank you and Marc. > > > > Nit: you don't really need another pointer (ie tmp) but you may keep > > it if that makes the code clearer - all you need to do is using > > platform_timer as an iterator and initialize > > > Yes, the tmp pointer can be removed for conciseness. > > Thanks! > > > > > > acpi_gtdt_desc.platform_timer = (void *)gtdt + gtdt->platform_timer_offset; > > > > if all checks passed (you are using tmp just because after the loop > > platform_timer can't be used to initialize acpi_gtdt_desc.platform_timer). > > > > Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org> > > > > (now let's see if this survives GTDTs out there :)) > > > struct acpi_table_gtdt *gtdt; > > > + int cnt = 0; > > > gtdt = container_of(table, struct acpi_table_gtdt, header); > > > acpi_gtdt_desc.gtdt = gtdt; > > > @@ -177,7 +184,10 @@ int __init acpi_gtdt_init(struct acpi_table_header *table, > > > } > > > platform_timer = (void *)gtdt + gtdt->platform_timer_offset; > > > - if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) { > > > + for_each_platform_timer(tmp, platform_timer) > > > + cnt++; > > > + > > > + if (cnt != gtdt->platform_timer_count) { > > > pr_err(FW_BUG "invalid timer data.\n"); > > > return -EINVAL; > > > } > > > @@ -305,7 +315,7 @@ int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, > > > void *platform_timer; > > > *timer_count = 0; > > > - for_each_platform_timer(platform_timer) { > > > + for_each_platform_timer(platform_timer, acpi_gtdt_desc.platform_timer) { > > > if (is_timer_block(platform_timer)) { > > > ret = gtdt_parse_timer_block(platform_timer, timer_mem); > > > if (ret) > > > @@ -398,7 +408,7 @@ static int __init gtdt_sbsa_gwdt_init(void) > > > if (ret || !timer_count) > > > goto out_put_gtdt; > > > - for_each_platform_timer(platform_timer) { > > > + for_each_platform_timer(platform_timer, acpi_gtdt_desc.platform_timer) { > > > if (is_non_secure_watchdog(platform_timer)) { > > > ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); > > > if (ret) > > > -- > > > 2.20.1 > > > > > . > >
diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c index c0e77c1c8e09..3583c99afb0d 100644 --- a/drivers/acpi/arm64/gtdt.c +++ b/drivers/acpi/arm64/gtdt.c @@ -36,19 +36,25 @@ struct acpi_gtdt_descriptor { static struct acpi_gtdt_descriptor acpi_gtdt_desc __initdata; -static inline __init void *next_platform_timer(void *platform_timer) +static __init bool platform_timer_valid(void *platform_timer) { struct acpi_gtdt_header *gh = platform_timer; - platform_timer += gh->length; - if (platform_timer < acpi_gtdt_desc.gtdt_end) - return platform_timer; + return (platform_timer >= (void *)(acpi_gtdt_desc.gtdt + 1) && + platform_timer < acpi_gtdt_desc.gtdt_end && + gh->length != 0 && + platform_timer + gh->length <= acpi_gtdt_desc.gtdt_end); +} + +static __init void *next_platform_timer(void *platform_timer) +{ + struct acpi_gtdt_header *gh = platform_timer; - return NULL; + return platform_timer + gh->length; } -#define for_each_platform_timer(_g) \ - for (_g = acpi_gtdt_desc.platform_timer; _g; \ +#define for_each_platform_timer(_g, first_entry) \ + for (_g = first_entry; platform_timer_valid(_g); \ _g = next_platform_timer(_g)) static inline bool is_timer_block(void *platform_timer) @@ -155,8 +161,9 @@ bool __init acpi_gtdt_c3stop(int type) int __init acpi_gtdt_init(struct acpi_table_header *table, int *platform_timer_count) { - void *platform_timer; + void *platform_timer, *tmp; struct acpi_table_gtdt *gtdt; + int cnt = 0; gtdt = container_of(table, struct acpi_table_gtdt, header); acpi_gtdt_desc.gtdt = gtdt; @@ -177,7 +184,10 @@ int __init acpi_gtdt_init(struct acpi_table_header *table, } platform_timer = (void *)gtdt + gtdt->platform_timer_offset; - if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) { + for_each_platform_timer(tmp, platform_timer) + cnt++; + + if (cnt != gtdt->platform_timer_count) { pr_err(FW_BUG "invalid timer data.\n"); return -EINVAL; } @@ -305,7 +315,7 @@ int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, void *platform_timer; *timer_count = 0; - for_each_platform_timer(platform_timer) { + for_each_platform_timer(platform_timer, acpi_gtdt_desc.platform_timer) { if (is_timer_block(platform_timer)) { ret = gtdt_parse_timer_block(platform_timer, timer_mem); if (ret) @@ -398,7 +408,7 @@ static int __init gtdt_sbsa_gwdt_init(void) if (ret || !timer_count) goto out_put_gtdt; - for_each_platform_timer(platform_timer) { + for_each_platform_timer(platform_timer, acpi_gtdt_desc.platform_timer) { if (is_non_secure_watchdog(platform_timer)) { ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); if (ret)