| Message ID | 20240819110729.205707-1-frediano.ziglio@cloud.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Avoid crash calling PrintErrMesg from efi_multiboot2 | expand |
On 19.08.2024 13:07, Frediano Ziglio wrote: > --- a/xen/common/efi/boot.c > +++ b/xen/common/efi/boot.c > @@ -287,19 +287,36 @@ static bool __init match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2) > /* generic routine for printing error messages */ > static void __init PrintErrMesg(const CHAR16 *mesg, EFI_STATUS ErrCode) > { > - static const CHAR16* const ErrCodeToStr[] __initconstrel = { > - [~EFI_ERROR_MASK & EFI_NOT_FOUND] = L"Not found", > - [~EFI_ERROR_MASK & EFI_NO_MEDIA] = L"The device has no media", > - [~EFI_ERROR_MASK & EFI_MEDIA_CHANGED] = L"Media changed", > - [~EFI_ERROR_MASK & EFI_DEVICE_ERROR] = L"Device error", > - [~EFI_ERROR_MASK & EFI_VOLUME_CORRUPTED] = L"Volume corrupted", > - [~EFI_ERROR_MASK & EFI_ACCESS_DENIED] = L"Access denied", > - [~EFI_ERROR_MASK & EFI_OUT_OF_RESOURCES] = L"Out of resources", > - [~EFI_ERROR_MASK & EFI_VOLUME_FULL] = L"Volume is full", > - [~EFI_ERROR_MASK & EFI_SECURITY_VIOLATION] = L"Security violation", > - [~EFI_ERROR_MASK & EFI_CRC_ERROR] = L"CRC error", > - [~EFI_ERROR_MASK & EFI_COMPROMISED_DATA] = L"Compromised data", > - [~EFI_ERROR_MASK & EFI_BUFFER_TOO_SMALL] = L"Buffer too small", > +#define ERROR_MESSAGE_LIST \ > + ERROR_MESSAGE(EFI_NOT_FOUND, "Not found") \ > + ERROR_MESSAGE(EFI_NO_MEDIA, "The device has no media") \ > + ERROR_MESSAGE(EFI_MEDIA_CHANGED, "Media changed") \ > + ERROR_MESSAGE(EFI_DEVICE_ERROR, "Device error") \ > + ERROR_MESSAGE(EFI_VOLUME_CORRUPTED, "Volume corrupted") \ > + ERROR_MESSAGE(EFI_ACCESS_DENIED, "Access denied") \ > + ERROR_MESSAGE(EFI_OUT_OF_RESOURCES, "Out of resources") \ > + ERROR_MESSAGE(EFI_VOLUME_FULL, "Volume is full") \ > + ERROR_MESSAGE(EFI_SECURITY_VIOLATION, "Security violation") \ > + ERROR_MESSAGE(EFI_CRC_ERROR, "CRC error") \ > + ERROR_MESSAGE(EFI_COMPROMISED_DATA, "Compromised data") \ > + ERROR_MESSAGE(EFI_BUFFER_TOO_SMALL, "Buffer too small") > + > + static const struct ErrorStrings { __initconst? > + CHAR16 start; > +#undef ERROR_MESSAGE > +#define ERROR_MESSAGE(code, str) CHAR16 msg_ ## code[sizeof(str)]; > + ERROR_MESSAGE_LIST > + } ErrorStrings __initconst = { > + 0 > +#undef ERROR_MESSAGE > +#define ERROR_MESSAGE(code, str) , L ## str > + ERROR_MESSAGE_LIST > + }; > + static const uint16_t ErrCodeToStr[] __initconst = { > +#undef ERROR_MESSAGE > +#define ERROR_MESSAGE(code, str) \ > + [~EFI_ERROR_MASK & code] = offsetof(struct ErrorStrings, msg_ ## code), > + ERROR_MESSAGE_LIST > }; > EFI_STATUS ErrIdx = ErrCode & ~EFI_ERROR_MASK; > > @@ -308,7 +325,7 @@ static void __init PrintErrMesg(const CHAR16 *mesg, EFI_STATUS ErrCode) > PrintErr(L": "); > > if( (ErrIdx < ARRAY_SIZE(ErrCodeToStr)) && ErrCodeToStr[ErrIdx] ) > - mesg = ErrCodeToStr[ErrIdx]; > + mesg = (CHAR16*) ((char*) &ErrorStrings + ErrCodeToStr[ErrIdx]); Please never cast away const. Also (nit) please put the blanks at the right places. Finally instead of casting to char * (something string-like) intermediately, perhaps better cast to void *? Taken together mesg = (const CHAR16 *)((const void *)&ErrorStrings + ErrCodeToStr[ErrIdx]); (which looks like it'll then also need line-wrapping). Further please add an appropriate Fixes: tag. Jan
On Mon, Aug 19, 2024 at 12:35 PM Jan Beulich <jbeulich@suse.com> wrote: > > On 19.08.2024 13:07, Frediano Ziglio wrote: > > --- a/xen/common/efi/boot.c > > +++ b/xen/common/efi/boot.c > > @@ -287,19 +287,36 @@ static bool __init match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2) > > /* generic routine for printing error messages */ > > static void __init PrintErrMesg(const CHAR16 *mesg, EFI_STATUS ErrCode) > > { > > - static const CHAR16* const ErrCodeToStr[] __initconstrel = { > > - [~EFI_ERROR_MASK & EFI_NOT_FOUND] = L"Not found", > > - [~EFI_ERROR_MASK & EFI_NO_MEDIA] = L"The device has no media", > > - [~EFI_ERROR_MASK & EFI_MEDIA_CHANGED] = L"Media changed", > > - [~EFI_ERROR_MASK & EFI_DEVICE_ERROR] = L"Device error", > > - [~EFI_ERROR_MASK & EFI_VOLUME_CORRUPTED] = L"Volume corrupted", > > - [~EFI_ERROR_MASK & EFI_ACCESS_DENIED] = L"Access denied", > > - [~EFI_ERROR_MASK & EFI_OUT_OF_RESOURCES] = L"Out of resources", > > - [~EFI_ERROR_MASK & EFI_VOLUME_FULL] = L"Volume is full", > > - [~EFI_ERROR_MASK & EFI_SECURITY_VIOLATION] = L"Security violation", > > - [~EFI_ERROR_MASK & EFI_CRC_ERROR] = L"CRC error", > > - [~EFI_ERROR_MASK & EFI_COMPROMISED_DATA] = L"Compromised data", > > - [~EFI_ERROR_MASK & EFI_BUFFER_TOO_SMALL] = L"Buffer too small", > > +#define ERROR_MESSAGE_LIST \ > > + ERROR_MESSAGE(EFI_NOT_FOUND, "Not found") \ > > + ERROR_MESSAGE(EFI_NO_MEDIA, "The device has no media") \ > > + ERROR_MESSAGE(EFI_MEDIA_CHANGED, "Media changed") \ > > + ERROR_MESSAGE(EFI_DEVICE_ERROR, "Device error") \ > > + ERROR_MESSAGE(EFI_VOLUME_CORRUPTED, "Volume corrupted") \ > > + ERROR_MESSAGE(EFI_ACCESS_DENIED, "Access denied") \ > > + ERROR_MESSAGE(EFI_OUT_OF_RESOURCES, "Out of resources") \ > > + ERROR_MESSAGE(EFI_VOLUME_FULL, "Volume is full") \ > > + ERROR_MESSAGE(EFI_SECURITY_VIOLATION, "Security violation") \ > > + ERROR_MESSAGE(EFI_CRC_ERROR, "CRC error") \ > > + ERROR_MESSAGE(EFI_COMPROMISED_DATA, "Compromised data") \ > > + ERROR_MESSAGE(EFI_BUFFER_TOO_SMALL, "Buffer too small") > > + > > + static const struct ErrorStrings { > > __initconst? > It's below, attached to the variable, it cannot be attached to a structure declaration. > > + CHAR16 start; > > +#undef ERROR_MESSAGE > > +#define ERROR_MESSAGE(code, str) CHAR16 msg_ ## code[sizeof(str)]; > > + ERROR_MESSAGE_LIST > > + } ErrorStrings __initconst = { Here it is. > > + 0 > > +#undef ERROR_MESSAGE > > +#define ERROR_MESSAGE(code, str) , L ## str > > + ERROR_MESSAGE_LIST > > + }; > > + static const uint16_t ErrCodeToStr[] __initconst = { > > +#undef ERROR_MESSAGE > > +#define ERROR_MESSAGE(code, str) \ > > + [~EFI_ERROR_MASK & code] = offsetof(struct ErrorStrings, msg_ ## code), > > + ERROR_MESSAGE_LIST > > }; > > EFI_STATUS ErrIdx = ErrCode & ~EFI_ERROR_MASK; > > > > @@ -308,7 +325,7 @@ static void __init PrintErrMesg(const CHAR16 *mesg, EFI_STATUS ErrCode) > > PrintErr(L": "); > > > > if( (ErrIdx < ARRAY_SIZE(ErrCodeToStr)) && ErrCodeToStr[ErrIdx] ) > > - mesg = ErrCodeToStr[ErrIdx]; > > + mesg = (CHAR16*) ((char*) &ErrorStrings + ErrCodeToStr[ErrIdx]); > > Please never cast away const. Also (nit) please put the blanks at the right > places. Finally instead of casting to char * (something string-like) > intermediately, perhaps better cast to void *? Taken together > > mesg = (const CHAR16 *)((const void *)&ErrorStrings + ErrCodeToStr[ErrIdx]); > Done, less portable but it's not portable code. > (which looks like it'll then also need line-wrapping). > > Further please add an appropriate Fixes: tag. > Done > Jan Frediano
diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c index efbec00af9..e6aa9271ed 100644 --- a/xen/common/efi/boot.c +++ b/xen/common/efi/boot.c @@ -287,19 +287,36 @@ static bool __init match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2) /* generic routine for printing error messages */ static void __init PrintErrMesg(const CHAR16 *mesg, EFI_STATUS ErrCode) { - static const CHAR16* const ErrCodeToStr[] __initconstrel = { - [~EFI_ERROR_MASK & EFI_NOT_FOUND] = L"Not found", - [~EFI_ERROR_MASK & EFI_NO_MEDIA] = L"The device has no media", - [~EFI_ERROR_MASK & EFI_MEDIA_CHANGED] = L"Media changed", - [~EFI_ERROR_MASK & EFI_DEVICE_ERROR] = L"Device error", - [~EFI_ERROR_MASK & EFI_VOLUME_CORRUPTED] = L"Volume corrupted", - [~EFI_ERROR_MASK & EFI_ACCESS_DENIED] = L"Access denied", - [~EFI_ERROR_MASK & EFI_OUT_OF_RESOURCES] = L"Out of resources", - [~EFI_ERROR_MASK & EFI_VOLUME_FULL] = L"Volume is full", - [~EFI_ERROR_MASK & EFI_SECURITY_VIOLATION] = L"Security violation", - [~EFI_ERROR_MASK & EFI_CRC_ERROR] = L"CRC error", - [~EFI_ERROR_MASK & EFI_COMPROMISED_DATA] = L"Compromised data", - [~EFI_ERROR_MASK & EFI_BUFFER_TOO_SMALL] = L"Buffer too small", +#define ERROR_MESSAGE_LIST \ + ERROR_MESSAGE(EFI_NOT_FOUND, "Not found") \ + ERROR_MESSAGE(EFI_NO_MEDIA, "The device has no media") \ + ERROR_MESSAGE(EFI_MEDIA_CHANGED, "Media changed") \ + ERROR_MESSAGE(EFI_DEVICE_ERROR, "Device error") \ + ERROR_MESSAGE(EFI_VOLUME_CORRUPTED, "Volume corrupted") \ + ERROR_MESSAGE(EFI_ACCESS_DENIED, "Access denied") \ + ERROR_MESSAGE(EFI_OUT_OF_RESOURCES, "Out of resources") \ + ERROR_MESSAGE(EFI_VOLUME_FULL, "Volume is full") \ + ERROR_MESSAGE(EFI_SECURITY_VIOLATION, "Security violation") \ + ERROR_MESSAGE(EFI_CRC_ERROR, "CRC error") \ + ERROR_MESSAGE(EFI_COMPROMISED_DATA, "Compromised data") \ + ERROR_MESSAGE(EFI_BUFFER_TOO_SMALL, "Buffer too small") + + static const struct ErrorStrings { + CHAR16 start; +#undef ERROR_MESSAGE +#define ERROR_MESSAGE(code, str) CHAR16 msg_ ## code[sizeof(str)]; + ERROR_MESSAGE_LIST + } ErrorStrings __initconst = { + 0 +#undef ERROR_MESSAGE +#define ERROR_MESSAGE(code, str) , L ## str + ERROR_MESSAGE_LIST + }; + static const uint16_t ErrCodeToStr[] __initconst = { +#undef ERROR_MESSAGE +#define ERROR_MESSAGE(code, str) \ + [~EFI_ERROR_MASK & code] = offsetof(struct ErrorStrings, msg_ ## code), + ERROR_MESSAGE_LIST }; EFI_STATUS ErrIdx = ErrCode & ~EFI_ERROR_MASK; @@ -308,7 +325,7 @@ static void __init PrintErrMesg(const CHAR16 *mesg, EFI_STATUS ErrCode) PrintErr(L": "); if( (ErrIdx < ARRAY_SIZE(ErrCodeToStr)) && ErrCodeToStr[ErrIdx] ) - mesg = ErrCodeToStr[ErrIdx]; + mesg = (CHAR16*) ((char*) &ErrorStrings + ErrCodeToStr[ErrIdx]); else { PrintErr(L"ErrCode: ");
Although code is compiled with -fpic option data is not position independent. This causes data pointer to become invalid if code is not relocated properly which is what happens for efi_multiboot2 which is called by multiboot entry code. Code tested adding PrintErrMesg(L"Test message", EFI_BUFFER_TOO_SMALL); in efi_multiboot2 before calling efi_arch_edd (this function can potentially call PrintErrMesg). Before the patch (XenServer installation on Qemu, xen replaced with vanilla xen.gz): Booting `XenServer (Serial)'Booting `XenServer (Serial)' Test message: !!!! X64 Exception Type - 0E(#PF - Page-Fault) CPU Apic ID - 00000000 !!!! ExceptionData - 0000000000000000 I:0 R:0 U:0 W:0 P:0 PK:0 SS:0 SGX:0 RIP - 000000007DC29E46, CS - 0000000000000038, RFLAGS - 0000000000210246 RAX - 0000000000000000, RCX - 0000000000000050, RDX - 0000000000000000 RBX - 000000007DAB4558, RSP - 000000007EFA1200, RBP - 0000000000000000 RSI - FFFF82D040467A88, RDI - 0000000000000000 R8 - 000000007EFA1238, R9 - 000000007EFA1230, R10 - 0000000000000000 R11 - 000000007CF42665, R12 - FFFF82D040467A88, R13 - 000000007EFA1228 R14 - 000000007EFA1225, R15 - 000000007DAB45A8 DS - 0000000000000030, ES - 0000000000000030, FS - 0000000000000030 GS - 0000000000000030, SS - 0000000000000030 CR0 - 0000000080010033, CR2 - FFFF82D040467A88, CR3 - 000000007EC01000 CR4 - 0000000000000668, CR8 - 0000000000000000 DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000 DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400 GDTR - 000000007E9E2000 0000000000000047, LDTR - 0000000000000000 IDTR - 000000007E4E5018 0000000000000FFF, TR - 0000000000000000 FXSAVE_STATE - 000000007EFA0E60 !!!! Find image based on IP(0x7DC29E46) (No PDB) (ImageBase=000000007DC28000, EntryPoint=000000007DC2B917) !!!! After the patch: Booting `XenServer (Serial)'Booting `XenServer (Serial)' Test message: Buffer too small BdsDxe: loading Boot0000 "UiApp" from Fv(7CB8BDC9-F8EB-4F34-AAEA-3EE4AF6516A1)/FvFile(462CAA21-7614-4503-836E-8AB6F4662331) BdsDxe: starting Boot0000 "UiApp" from Fv(7CB8BDC9-F8EB-4F34-AAEA-3EE4AF6516A1)/FvFile(462CAA21-7614-4503-836E-8AB6F4662331) Signed-off-by: Frediano Ziglio <frediano.ziglio@cloud.com> --- xen/common/efi/boot.c | 45 +++++++++++++++++++++++++++++-------------- 1 file changed, 31 insertions(+), 14 deletions(-)