| Message ID | 20240131001851.15932-1-iii@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | linux-user: Make TARGET_NR_setgroups affect only the current thread | expand |
On 1/31/24 01:18, Ilya Leoshkevich wrote: > Like TARGET_NR_setuid, TARGET_NR_setgroups should affect only the > calling thread, and not the entire process. Therefore, implement it > using a syscall, and not a libc call. > > Cc: qemu-stable@nongnu.org > Fixes: 19b84f3c35d7 ("added setgroups and getgroups syscalls") > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Patch seems ok, but just out of interest, how did you noticed? Helge > --- > linux-user/syscall.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/linux-user/syscall.c b/linux-user/syscall.c > index ff245dade51..da15d727e16 100644 > --- a/linux-user/syscall.c > +++ b/linux-user/syscall.c > @@ -7203,11 +7203,17 @@ static inline int tswapid(int id) > #else > #define __NR_sys_setresgid __NR_setresgid > #endif > +#ifdef __NR_setgroups32 > +#define __NR_sys_setgroups __NR_setgroups32 > +#else > +#define __NR_sys_setgroups __NR_setgroups > +#endif > > _syscall1(int, sys_setuid, uid_t, uid) > _syscall1(int, sys_setgid, gid_t, gid) > _syscall3(int, sys_setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) > _syscall3(int, sys_setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) > +_syscall2(int, sys_setgroups, int, size, gid_t *, grouplist) > > void syscall_init(void) > { > @@ -11772,7 +11778,7 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1, > unlock_user(target_grouplist, arg2, > gidsetsize * sizeof(target_id)); > } > - return get_errno(setgroups(gidsetsize, grouplist)); > + return get_errno(sys_setgroups(gidsetsize, grouplist)); > } > case TARGET_NR_fchown: > return get_errno(fchown(arg1, low2highuid(arg2), low2highgid(arg3))); > @@ -12108,7 +12114,7 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1, > } > unlock_user(target_grouplist, arg2, 0); > } > - return get_errno(setgroups(gidsetsize, grouplist)); > + return get_errno(sys_setgroups(gidsetsize, grouplist)); > } > #endif > #ifdef TARGET_NR_fchown32
On Wed, Jan 31, 2024 at 08:53:49AM +0100, Helge Deller wrote: > On 1/31/24 01:18, Ilya Leoshkevich wrote: > > Like TARGET_NR_setuid, TARGET_NR_setgroups should affect only the > > calling thread, and not the entire process. Therefore, implement it > > using a syscall, and not a libc call. > > > > Cc: qemu-stable@nongnu.org > > Fixes: 19b84f3c35d7 ("added setgroups and getgroups syscalls") > > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > > Patch seems ok, but just out of interest, how did you noticed? > > Helge Our internal users are trying to emulate a larger app, and they were running into weird crashes between fork() and exec(). I had to implement syscall catchpoints (posted) and follow-fork-mode child (still needs a few cleanups before I can post it) to be able to debug it, and found it was dying here [1], and from there it was easy. [1] https://sourceware.org/git/?p=glibc.git;a=blob;f=nptl/nptl_setxid.c;h=4bfcfe41882d9b15b8090325bfdc9ceb5ab2693e;hb=36f2487f13e3540be9ee0fb51876b1da72176d3f#l25
On 31/1/24 01:18, Ilya Leoshkevich wrote: > Like TARGET_NR_setuid, TARGET_NR_setgroups should affect only the > calling thread, and not the entire process. Therefore, implement it > using a syscall, and not a libc call. > > Cc: qemu-stable@nongnu.org > Fixes: 19b84f3c35d7 ("added setgroups and getgroups syscalls") > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > --- > linux-user/syscall.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
On Wed, Jan 31, 2024 at 02:10:55PM +0100, Philippe Mathieu-Daudé wrote: > On 31/1/24 01:18, Ilya Leoshkevich wrote: > > Like TARGET_NR_setuid, TARGET_NR_setgroups should affect only the > > calling thread, and not the entire process. Therefore, implement it > > using a syscall, and not a libc call. > > > > Cc: qemu-stable@nongnu.org > > Fixes: 19b84f3c35d7 ("added setgroups and getgroups syscalls") > > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > > --- > > linux-user/syscall.c | 10 ++++++++-- > > 1 file changed, 8 insertions(+), 2 deletions(-) > > Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Thanks for the review! A few weeks have passed and I wonder if this patch fell through the cracks. Do I need to do something to have it applied?
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index ff245dade51..da15d727e16 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -7203,11 +7203,17 @@ static inline int tswapid(int id) #else #define __NR_sys_setresgid __NR_setresgid #endif +#ifdef __NR_setgroups32 +#define __NR_sys_setgroups __NR_setgroups32 +#else +#define __NR_sys_setgroups __NR_setgroups +#endif _syscall1(int, sys_setuid, uid_t, uid) _syscall1(int, sys_setgid, gid_t, gid) _syscall3(int, sys_setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) _syscall3(int, sys_setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) +_syscall2(int, sys_setgroups, int, size, gid_t *, grouplist) void syscall_init(void) { @@ -11772,7 +11778,7 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1, unlock_user(target_grouplist, arg2, gidsetsize * sizeof(target_id)); } - return get_errno(setgroups(gidsetsize, grouplist)); + return get_errno(sys_setgroups(gidsetsize, grouplist)); } case TARGET_NR_fchown: return get_errno(fchown(arg1, low2highuid(arg2), low2highgid(arg3))); @@ -12108,7 +12114,7 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1, } unlock_user(target_grouplist, arg2, 0); } - return get_errno(setgroups(gidsetsize, grouplist)); + return get_errno(sys_setgroups(gidsetsize, grouplist)); } #endif #ifdef TARGET_NR_fchown32
Like TARGET_NR_setuid, TARGET_NR_setgroups should affect only the calling thread, and not the entire process. Therefore, implement it using a syscall, and not a libc call. Cc: qemu-stable@nongnu.org Fixes: 19b84f3c35d7 ("added setgroups and getgroups syscalls") Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> --- linux-user/syscall.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)