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Rename 'msecs' to 'usecs' to avoid potential confusion #563
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The function msleep uses gBS->Stall which waits for a specified number of microseconds. Reference: https://edk2-docs.gitbook.io/edk-ii-uefi-driver-writer-s-guide/5_uefi_services/51_services_that_uefi_drivers_commonly_use/517_stall This reference even mentions an example slepping for 10 microseconds: // Wait 10 uS. Notice the letter 'u'. Therefore it's a good idea to call the argument msleep uses 'usecs' rather than 'msecs' so no one confuses it with miliseconds. Signed-off-by: Kamil Aronowski <[email protected]>
Normally, parameter usecs is used for usleep(useconds_t usec), and msecs is used for msleep(unsigned int msecs). Hence, to avoid confusion, could we also change the function name from msleep() to usleep() ? |
I like this idea but the implementation of it may be more complex than I initially thought. I'm not a developer as of today and I'm unsure if such a change won't break anything crucial. I don't want to introduce major changes especially for a security-critical component such as Shim. Changing argument names only resulted in the exact same binary, while changing function names results in a binary with a different checksum. While it works fine and allows for booting a system with Secure Boot enabled, I'm unsure if I should do this. Maybe I'll let the Red Hat Bootloader Team decide on this. |
The function name should be changed as well. |
@aronowski If you don't mind, please let me change the function name and its argument as well in another PR according to vathpela's suggestion. |
Normally, parameter usecs is used for usleep(useconds_t usec), and msecs is used for msleep(unsigned int msecs). This commit changes the function name from msleep() to usleep() to avoid futher confusion. Signed-off-by: Kamil Aronowski <[email protected]>
The function has been renamed according to Peter's request. @dennis-tseng99 I did this change once I saw my first email notification rather than following the complete conversation. You can, however, review the latest commit so I can be sure I haven't made any mistake. |
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In fallback.c, would you please also change int fallback_verbose_wait to unsigned long ?
1009 - int fallback_verbose_wait = 500000; /* default to 0.5s */
1009 + unsigned long fallback_verbose_wait = 500000; /* default to 0.5s */
1016 usleep(fallback_verbose_wait);
1214 - int fallback_verbose_wait = 500000; /* default to 0.5s */
1214 + unsigned long fallback_verbose_wait = 500000; /* default to 0.5s */
1221 usleep(fallback_verbose_wait);
I think wrapping the decl in a test for
|
In some cases tests were failing due to a mismatch between our declaration of the usleep() function and what is being provided by unistd.h. This change simply makes our function declared only when not in a unit test environment. Signed-off-by: Kamil Aronowski <[email protected]>
The variable fallback_verbose_wait from now on is of the type unsigned long to match the type of the argument usleep() accepts. Signed-off-by: Kamil Aronowski <[email protected]>
@dennis-tseng99 @vathpela |
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Except header file, may I suggest we also add "#ifndef SHIM_UNIT_TEST" to the function itself ?
/* lib/console.c */
#ifndef SHIM_UNIT_TEST
VOID
usleep(unsigned long usecs)
{
BS->Stall(usecs);
}
#endif
As suggested in rhboot#563 (review) Signed-off-by: Kamil Aronowski <[email protected]>
Sure thing. It's right there! 😀 |
What's changed * Various CVE fixes: CVE-2023-40546 mok: fix LogError() invocation CVE-2023-40547 - avoid incorrectly trusting HTTP headers CVE-2023-40548 Fix integer overflow on SBAT section size on 32-bit system CVE-2023-40549 Authenticode: verify that the signature header is in bounds. CVE-2023-40550 pe: Fix an out-of-bound read in verify_buffer_sbat() CVE-2023-40551: pe-relocate: Fix bounds check for MZ binaries * Add make infrastructure to set the NX_COMPAT flag by @vathpela in #530 * Make sbat_var.S parse right with buggy gcc/binutils by @vathpela in #535 * Drop invalid calls to CRYPTO_set_mem_functions by @nicholasbishop in #537 * pe: Align section size up to page size for mem attrs by @nicholasbishop in #539 * test-sbat: Fix exit code by @vathpela in #540 * pe: Add IS_PAGE_ALIGNED macro by @nicholasbishop in #541 * CryptoPkg/BaseCryptLib: Fix buffer overflow issue in realloc wrapper by @nicholasbishop in #546 * Don't loop forever in load_certs() with buggy firmware by @rmetrich in #547 * Block Debian grub binaries with SBAT < 4 by @steve-mcintyre in #550 * Shim unable to locate grubx64 in PXE boot mode when grubx64 is stored in a different file path by @Alberto-Perez-Guevara in #551 * Further improve load_certs() for non-compliant drivers/firmwares by @pbatard in #560 * pe: only process RelocDir->Size of reloc section by @mikebeaton in #562 * Rename 'msecs' to 'usecs' to avoid potential confusion by @aronowski in #563 * Optionally allow to keep shim protocol installed by @bluca in #565 * SBAT-related documents formatting and spelling by @aronowski in #566 * Add SbatLevel_Variable.txt to document the various revocations by @jsetje in #569 * Add a security contact email address in README.md by @vathpela in #572 * Use -Wno-unused-but-set-variable for Cryptlib and OpenSSL by @vathpela in #576 * mok: fix LogError() invocation by @vathpela in #577 * Minor housekeeping by @vathpela in #578 * Test ImageAddress() by @vathpela in #579 * FreePages() is used to return memory allocated by AllocatePages() by @dennis-tseng99 in #580 * Size should minus 1 when calculating 'RelocBaseEnd' by @jsetje in #581 * Verify signature before verifying sbat levels by @jsetje in #583 * Add libFuzzer support for csv.c and sbat.c by @vathpela in #584 * mok: Avoid underflow in maximum variable size calculation by @alpernebbi in #587 * Housekeeping by @vathpela in #605 Signed-off-by: Peter Jones <[email protected]>
What's changed * Various CVE fixes: CVE-2023-40546 mok: fix LogError() invocation CVE-2023-40547 - avoid incorrectly trusting HTTP headers CVE-2023-40548 Fix integer overflow on SBAT section size on 32-bit system CVE-2023-40549 Authenticode: verify that the signature header is in bounds. CVE-2023-40550 pe: Fix an out-of-bound read in verify_buffer_sbat() CVE-2023-40551: pe-relocate: Fix bounds check for MZ binaries * Add make infrastructure to set the NX_COMPAT flag by @vathpela in rhboot#530 * Make sbat_var.S parse right with buggy gcc/binutils by @vathpela in rhboot#535 * Drop invalid calls to CRYPTO_set_mem_functions by @nicholasbishop in rhboot#537 * pe: Align section size up to page size for mem attrs by @nicholasbishop in rhboot#539 * test-sbat: Fix exit code by @vathpela in rhboot#540 * pe: Add IS_PAGE_ALIGNED macro by @nicholasbishop in rhboot#541 * CryptoPkg/BaseCryptLib: Fix buffer overflow issue in realloc wrapper by @nicholasbishop in rhboot#546 * Don't loop forever in load_certs() with buggy firmware by @rmetrich in rhboot#547 * Block Debian grub binaries with SBAT < 4 by @steve-mcintyre in rhboot#550 * Shim unable to locate grubx64 in PXE boot mode when grubx64 is stored in a different file path by @Alberto-Perez-Guevara in rhboot#551 * Further improve load_certs() for non-compliant drivers/firmwares by @pbatard in rhboot#560 * pe: only process RelocDir->Size of reloc section by @mikebeaton in rhboot#562 * Rename 'msecs' to 'usecs' to avoid potential confusion by @aronowski in rhboot#563 * Optionally allow to keep shim protocol installed by @bluca in rhboot#565 * SBAT-related documents formatting and spelling by @aronowski in rhboot#566 * Add SbatLevel_Variable.txt to document the various revocations by @jsetje in rhboot#569 * Add a security contact email address in README.md by @vathpela in rhboot#572 * Use -Wno-unused-but-set-variable for Cryptlib and OpenSSL by @vathpela in rhboot#576 * mok: fix LogError() invocation by @vathpela in rhboot#577 * Minor housekeeping by @vathpela in rhboot#578 * Test ImageAddress() by @vathpela in rhboot#579 * FreePages() is used to return memory allocated by AllocatePages() by @dennis-tseng99 in rhboot#580 * Size should minus 1 when calculating 'RelocBaseEnd' by @jsetje in rhboot#581 * Verify signature before verifying sbat levels by @jsetje in rhboot#583 * Add libFuzzer support for csv.c and sbat.c by @vathpela in rhboot#584 * mok: Avoid underflow in maximum variable size calculation by @alpernebbi in rhboot#587 * Housekeeping by @vathpela in rhboot#605 Signed-off-by: Peter Jones <[email protected]>
As suggested in #251.
The function
msleep
usesgBS->Stall
which waits for a specified number of microseconds.Reference: https://edk2-docs.gitbook.io/edk-ii-uefi-driver-writer-s-guide/5_uefi_services/51_services_that_uefi_drivers_commonly_use/517_stall
This reference even mentions an example slepping for 10 microseconds:
// Wait 10 uS
. Notice the letter 'u'.Therefore it's a good idea to call the argument
msleep
uses 'usecs' rather than 'msecs' so no one confuses it with miliseconds.